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HAYASHI Yoshi-yukiGraduate School of ScienceProfessor
Researcher basic information
■ Research Keyword- Geophysical Fluid Dynamics
- Earth and Planetary Atmospheric Science
- Earth and Planetary Science Informatics
- Natural sciences / Atmospheric and hydrospheric science / Geophysical Fluid Dynamics、Weather and Climate of Plnatetary Atmospheres
- Natural sciences / Space and planetary science / Geophysical Fluid Dynamics, Weather and Climate of Planetary Atmospheres
Research activity information
■ Award- May 2019 The Meteorological Society of Japan, Fujiwara Prize, Contribution in dveloping the fields of geophysical fluid dynamics and planetary atmospheric science, and information infrastructure
- Oct. 1987 The Meteorological Society of Japan, Yamamoto Prize, The 30-40 day oscillations simulated in an “aqua-planet” model. J. Meteor. Soc. Japan, 65, 451-467
- The asymptotic behavior of the profiles of mean zonal flows generated by thermal convection of a Boussinesq fluid in a rapidly rotating thin spherical shell was studied by extending the integration time of the numerical experiments of a previous study under similar conditions. Calculations were performed for the whole globe, as well as for a one-eighth sector region, with various values of the hyper-diffusion parameters. For sufficiently weak hyper-diffusion, a prograde zonal jet and alternating narrow zonal jets appeared at the equator and in the middle and high latitudes, respectively, as reported in the previous study. However, further integrations showed that the middle and high latitude flows are asymptotically accelerated eastward, jet peaks merge, and the banded zonal flow structure eventually disappears. Thus, the rotating thin spherical shell convection model of a Boussinesq fluid used in the previous studies seems inadequate to explain the surface banded structures of Jovian planetary atmospheres without modification of the standard setups. To maintain the alternating jet structure in the middle and high latitudes over the long-term, some sort of scale-independent dissipation process should be specified that prevents the evolution of zonal flows toward the long-term asymptotic state.Sep. 2024, Icarus, 420Scientific journal
- Meteorological Society of Japan, 2024, Journal of the Meteorological Society of Japan. Ser. II, 102(5) (5), 469 - 483Scientific journal
- Meteorological Society of Japan, 2024, Journal of the Meteorological Society of Japan. Ser. II, 102(1) (1), 5 - 16Scientific journal
- Feb. 2023, Journal of Space Science Informatics Japan, 12(1) (1), 41 - 49, Japanese[Refereed]Scientific journal
- Meteorological Society of Japan, 2023, Journal of the Meteorological Society of Japan. Ser. IIScientific journal
- Abstract The planetary missions including the Venus Climate Orbiter ‘Akatsuki’ provide new information on various atmospheric phenomena. Nevertheless, it is difficult to elucidate their three-dimensional structures globally and continuously only from observations because satellite observations are considerably limited in time and space. We constructed the first ‘objective analysis’ of Venus’ atmosphere by assimilating cloud-top horizontal winds on the dayside from the equator to mid-latitudes, which is frequently obtained from Akatsuki's Ultraviolet Imager (UVI). The three-dimensional structures of thermal tides, found recently to play a crucial role in maintaining the super rotation, are greatly improved by the data assimilation. This result is confirmed by comparison with Akatsuki's temperature observations. The momentum transport caused by the thermal tides and other disturbances are also modified by the wind assimilation and agrees well with those estimated from the UVI observations. The assimilated dataset is reliable and will be open to the public along with the Akatsuki observations for further investigation of Venus’ atmospheric phenomena.Springer Science and Business Media LLC, Aug. 2022, Scientific Reports, 12(1) (1)Scientific journal
- Springer Science and Business Media LLC, Dec. 2021, Nature Communications, 12(1) (1)
Abstract Gravity waves play essential roles in the terrestrial atmosphere because they propagate far from source regions and transport momentum and energy globally. Gravity waves are also observed in the Venus atmosphere, but their characteristics have been poorly understood. Here we demonstrate activities of small-scale gravity waves using a high-resolution Venus general circulation model with less than 20 and 0.25 km in the horizontal and vertical grid intervals, respectively. We find spontaneous gravity wave radiation from nearly balanced flows. In the upper cloud layer (~70 km), the thermal tides in the super-rotation are primary sources of small-scale gravity waves in the low-latitudes. Baroclinic/barotropic waves are also essential sources in the mid- and high-latitudes. The small-scale gravity waves affect the three-dimensional structure of the super-rotation and contribute to material mixing through their breaking processes. They propagate vertically and transport momentum globally, which decelerates the super-rotation in the upper cloud layer (~70 km) and accelerates it above ~80 km.Scientific journal - American Geophysical Union (AGU), Jun. 2021, Journal of Geophysical Research: Atmospheres, 126(11) (11), English[Refereed]Scientific journal
- Direct-imaging techniques of exoplanets have made significant progress recently and will eventually enable monitoring of photometric and spectroscopic signals of Earth-like habitable planets. The presence of clouds, however, would remain as one of the most uncertain components in deciphering such direct-imaged signals of planets. We attempt to examine how the planetary obliquity produces different cloud patterns by performing a series of general circulation model simulation runs using a set of parameters relevant for our Earth. Then we use the simulated photometric lightcurves to compute their frequency modulation that is due to the planetary spin-orbit coupling over an entire orbital period, and we attempt to see to what extent one can estimate the obliquity of an Earth twin. We find that it is possible to estimate the obliquity of an Earth twin within the uncertainty of several degrees with a dedicated 4 m space telescope at 10 pc away from the system if the stellar flux is completely blocked. While our conclusion is based on several idealized assumptions, a frequency modulation of a directly imaged Earth-like planet offers a unique methodology to determine its obliquity.American Astronomical Society, Jul. 2020, The Astrophysical Journal, 898(2) (2), 95 - 95, English[Refereed]Scientific journal
- American Association for the Advancement of Science (AAAS), Apr. 2020, Science, 368(6489) (6489), 405 - 409, English, International magazine[Refereed]Scientific journal
- Jan. 2019, Nature Communications, (10) (10), 23, English[Refereed]Scientific journal
- In order to investigate a possible variety of atmospheric states realized on a synchronously rotating aqua planet, an experiment studying the impact of planetary rotation rate is performed using an atmospheric general circulation model (GCM) with simplified hydrological and radiative processes. The entire planetary surface is covered with a swamp ocean. The value of planetary rotation rate is varied from zero to the Earth's, while other parameters such as planetary radius, mean molecular weight and total mass of atmospheric dry components, and solar constant are set to the present Earth's values. The integration results show that the atmosphere reaches statistically equilibrium states for all runs; none of the calculated cases exemplifies the runaway greenhouse state. The circulation patterns obtained are classified into four types: Type-I characterized by the dominance of a day-night thermally direct circulation, Type-II characterized by a zonal wave number one resonant Rossby wave over a meridionally broad westerly jet on the equator, Type-III characterized by a long time scale north-south asymmetric variation, and Type-IV characterized by a pair of mid-latitude westerly jets. With the increase of planetary rotation rate, the circulation evolves from Type-I to Type-II and then to Type-III gradually and smoothly, whereas the change from Type-Ill to Type-IV is abrupt and discontinuous. Over a finite range of planetary rotation rate, both Types-III and -IV emerge as statistically steady states, constituting multiple equilibria. In spite of the substantial changes in circulation, the net energy transport from the day side to the night side remains almost insensitive to planetary rotation rate, although the partition into dry static energy and latent heat energy transports changes. The reason for this notable insensitivity is that the outgoing longwave radiation over the broad area of the day side is constrained by the radiation limit of a moist atmosphere, so that the transport to the night side, which is determined as the difference between the incoming solar radiation and the radiation limit, cannot change greatly. (C) 2016 The Authors. Published by Elsevier Inc.ACADEMIC PRESS INC ELSEVIER SCIENCE, Jan. 2017, ICARUS, 282, 1 - 18, English[Refereed]Scientific journal
- American Meteorological Society, Oct. 2016, Journal of the Atmospheric Sciences, 73(10) (10), 4151 - 4169, English[Refereed]Scientific journal
- AKATSUKI is the Japanese Venus Climate Orbiter that was designed to investigate the climate system of Venus. The orbiter was launched on May 21, 2010, and it reached Venus on December 7, 2010. Thrust was applied by the orbital maneuver engine in an attempt to put AKATSUKI into a westward equatorial orbit around Venus with a 30-h orbital period. However, this operation failed because of a malfunction in the propulsion system. After this failure, the spacecraft orbited the Sun for 5 years. On December 7, 2015, AKATSUKI once again approached Venus and the Venus orbit insertion was successful, whereby a westward equatorial orbit with apoapsis of similar to 440,000 km and orbital period of 14 days was initiated. Now that AKATSUKI's long journey to Venus has ended, it will provide scientific data on the Venusian climate system for two or more years. For the purpose of both decreasing the apoapsis altitude and avoiding a long eclipse during the orbit, a trim maneuver was performed at the first periapsis. The apoapsis altitude is now similar to 360,000 km with a periapsis altitude of 1000-8000 km, and the period is 10 days and 12 h. In this paper, we describe the details of the Venus orbit insertion-revenge 1 (VOI-R1) and the new orbit, the expected scientific information to be obtained at this orbit, and the Venus images captured by the onboard 1-mu m infrared camera, ultraviolet imager, and long-wave infrared camera 2 h after the successful initiation of the VOI-R1.SPRINGER HEIDELBERG, May 2016, EARTH PLANETS AND SPACE, 68, 75, English[Refereed]Scientific journal
- Numerical simulations of the geodynamo have successfully represented many observable characteristics of the geomagnetic field, yielding insight into the fundamental processes that generate magnetic fields in the Earth's core. Because of limited spatial resolution, however, the diffusivities in numerical dynamo models are much larger than those in the Earth's core, and consequently, questions remain about how realistic these models are. The typical strategy used to address this issue has been to continue to increase the resolution of these quasi-laminar models with increasing computational resources, thus pushing them toward more realistic parameter regimes. We assess which methods are most promising for the next generation of supercomputers, which will offer access to O(10(6)) processor cores for large problems. Here we report performance and accuracy benchmarks from 15 dynamo codes that employ a range of numerical and parallelization methods. Computational performance is assessed on the basis of weak and strong scaling behavior up to 16,384 processor cores. Extrapolations of our weak-scaling results indicate that dynamo codes that employ two-dimensional or three-dimensional domain decompositions can perform efficiently on up to approximate to 10(6) processor cores, paving the way for more realistic simulations in the next model generation.AMER GEOPHYSICAL UNION, May 2016, GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS, 17(5) (5), 1586 - 1607, English[Refereed]Scientific journal
- 2016, Geophysical Research Letters, 43(9) (9), English[Refereed]Scientific journal
- Convection in planetary cores can generate fluid flow and magnetic fields, and a number of sophisticated codes exist to simulate the dynamic behaviour of such systems. We report on the first community activity to compare numerical results of computer codes designed to calculate fluid flow within a whole sphere. The flows are incompressible and rapidly rotating and the forcing of the flow is either due to thermal convection or due to moving boundaries. All problems defined have solutions that allow easy comparison, since they are either steady, slowly drifting or perfectly periodic. The first two benchmarks are defined based on uniform internal heating within the sphere under the Boussinesq approximation with boundary conditions that are uniform in temperature and stress-free for the flow. Benchmark 1 is purely hydrodynamic, and has a drifting solution. Benchmark 2 is a magnetohydrodynamic benchmark that can generate oscillatory, purely periodic, flows and magnetic fields. In contrast, Benchmark 3 is a hydrodynamic rotating bubble benchmark using no slip boundary conditions that has a stationary solution. Results from a variety of types of code are reported, including codes that are fully spectral (based on spherical harmonic expansions in angular coordinates and polynomial expansions in radius), mixed spectral and finite difference, finite volume, finite element and also a mixed Fourier-finite element code. There is good agreement between codes. It is found that in Benchmarks 1 and 2, the approximation of a whole sphere problem by a domain that is a spherical shell (a sphere possessing an inner core) does not represent an adequate approximation to the system, since the results differ from whole sphere results.OXFORD UNIV PRESS, Apr. 2014, GEOPHYSICAL JOURNAL INTERNATIONAL, 197(1) (1), 119 - 134, English[Refereed][Invited]Scientific journal
- ACADEMIC PRESS INC ELSEVIER SCIENCE, Mar. 2014, ICARUS, 231, 407 - 408, English
- A series of long-term numerical simulations of moist convection in Jupiter's atmosphere is performed in order to investigate the idealized characteristics of the vertical structure of multi-composition clouds and the convective motions associated with them, varying the deep abundances of condensable gases and the autoconversion time scale, the latter being one of the most questionable parameters in cloud microphysical parameterization. The simulations are conducted using a two-dimensional cloud resolving model that explicitly represents the convective motion and microphysics of the three cloud components, H2O, NH3, and NH4SH imposing a body cooling that substitutes the net radiative cooling. The results are qualitatively similar to those reported in Sugiyama et al. (Sugiyama, K. et al. [2011]. Intermittent cumulonimbus activity breaking the three-layer cloud structure of Jupiter. Geophys. Res. Lett. 38, L13201. doi:10.1029/2011GL047878): stable layers associated with condensation and chemical reaction act as effective dynamical and compositional boundaries, intense cumulonimbus clouds develop with distinct temporal intermittency, and the active transport associated with these clouds results in the establishment of mean vertical profiles of condensates and condensable gases that are distinctly different from the hitherto accepted three-layered structure (e.g., Atreya, S.K., Romani, P.N. [1985]. Photochemistry and clouds of Jupiter, Saturn and Uranus. In: Recent Advances in Planetary Meteorology. Cambridge Univ. Press, London, pp. 17-68). Our results also demonstrate that the period of intermittent cloud activity is roughly proportional to the deep abundance of H2O gas. The autoconversion time scale does not strongly affect the results, except for the vertical profiles of the condensates. Changing the autoconversion time scale by a factor of 100 changes the intermittency period by a factor of less than two, although it causes a dramatic increase in the amount of condensates in the upper troposphere. The moist convection layer becomes potentially unstable with respect to an air parcel rising from below the H2O lifting condensation level (LCL) well before the development of cumulonimbus clouds. The instability accumulates until an appropriate trigger is provided by the H2O condensate that falls down through the H2O LCL; the H2O condensate drives a downward flow below the H2O LCL as a result of the latent cooling associated with the re-evaporation of the condensate, and the returning updrafts carry moist air from below to the moist convection layer. Active cloud development is terminated when the instability is completely exhausted. The period of intermittency is roughly equal to the time obtained by dividing the mean temperature increase, which is caused by active cumulonimbus development, by the body cooling rate. 2013 The Authors. Published by Elsevier Inc. All rights reserved.ACADEMIC PRESS INC ELSEVIER SCIENCE, Feb. 2014, ICARUS, 229, 71 - 91, English[Refereed]Scientific journal
- It is frequently considered that many planetary magnetic fields originate as a result of convection within planetary cores. Buoyancy forces responsible for driving the convection generate a fluid flow that is able to induce magnetic fields; numerous sophisticated computer codes are able to simulate the dynamic behaviour of such systems. This paper reports the results of a community activity aimed at comparing numerical results of several different types of computer codes that are capable of solving the equations of momentum transfer, magnetic field generation and heat transfer in the setting of a spherical shell, namely a sphere containing an inner core. The electrically conducting fluid is incompressible and rapidly rotating and the forcing of the flow is thermal convection under the Boussinesq approximation. We follow the original specifications and results reported in Harder & Hansen to construct a specific benchmark in which the boundaries of the fluid are taken to be impenetrable, non-slip and isothermal, with the added boundary condition for the magnetic field B that the field must be entirely radial there; this type of boundary condition for B is frequently referred to as 'pseudovacuum'. This latter condition should be compared with the more frequently used insulating boundary condition. This benchmark is so-defined in order that computer codes based on local methods, such as finite element, finite volume or finite differences, can handle the boundary condition with ease. The defined benchmark, governed by specific choices of the Roberts, magnetic Rossby, Rayleigh and Ekman numbers, possesses a simple solution that is steady in an azimuthally drifting frame of reference, thus allowing easy comparison among results. Results from a variety of types of code are reported, including codes that are fully spectral (based on spherical harmonic expansions in angular coordinates and polynomial expansions in radius), mixed spectral and finite difference, finite volume, finite element and also a mixed Fourier-finite element code. There is good agreement among codes.OXFORD UNIV PRESS, Feb. 2014, GEOPHYSICAL JOURNAL INTERNATIONAL, 196(2) (2), 712 - 723, English[Refereed][Invited]Scientific journal
- Numerical experiments on an MHD dynamo in a rotating spherical shell are performed in order to examine effects of latitudinally heterogeneous buoyancy flux conditions at the inner core boundary on the establishment of dynamo solutions. The Ekman number, the Prandtl number, and the ratio of the inner to outer radii are fixed as 10-310-3, 1, and 0.350.35, respectively. The magnetElsevier {BV}, Oct. 2013, Physics of the Earth and Planetary Interiors, 223, 55 - 61, English[Refereed]Scientific journal
- METEOROLOGICAL SOC JAPAN, Sep. 2013, JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN, 91A, I - III, EnglishSpecial Issue on The Aqua-Planet Experiment Project (APE) and Related Researches Preface
- In this paper, we examine the steady state responses of models participating in the Aqua-Planet Experiment Project (APE) to the zonal asymmetry of equatorial sea surface temperature (SST) anomalies (SSTAs). Experiments were performed using three different SSTA distributions, i.e., two localized SSTAs with a common shape but different intensities, and an SSTA that varied with zonal wavenumber one. The structure of the responses obtained differs significantly among the models; however, some common features are also present.The principal features of the responses to the localized SSTAs are a positive precipitation anomaly over the warm SSTA, a widespread negative precipitation anomaly along the intertropical convergence zone, a pair of Rossby wavetrains along the equatorward flanks of mid-latitude westerly jets originating from a pair of upper tropospheric anticyclones that develop to the east of the warm SSTAs, and zonally wavelike precipitation and geopotential anomalies along the baroclinic zones. The structure of the tropical responses differs considerably from the Matsuno-Gill pattern, and the magnitude of the responses is almost proportional to the intensity of the localized SSTA in each of the models.The responses to the zonal wavenumber one SSTA are dominated by zonal wavenumber one structures. Around the longitudes of the warm (cold) SSTA, tropical precipitation increases (decreases). At longitudes east of the positive precipitation anomaly, the region of nearly zero absolute vorticity near the equator in the upper troposphere expands polewards, and the midlatitude westerly jets become narrower and stronger. To the west of the positive precipitation anomaly, the upper tropospheric region of nearly zero absolute vorticity shrinks, and the mid-latitude jets become weaker but broader, so that the regions of westerly winds extends to the equator, which results in the development of a zonal mean westerly wind anomaly around the equator. The longitudinal shift of the upper tropospheric westerly zonal wind anomaly relative to the precipitation anomaly is in marked contrast to that associated with the Walker circulation and the convection center around the Maritime Continent.METEOROLOGICAL SOC JAPAN, Sep. 2013, JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN, 91A, 143 - 193, English[Refereed]Scientific journal
- This paper explores the sensitivity of Atmospheric General Circulation Model (AGCM) simulations to changes in the meridional distribution of sea surface temperature (SST). The simulations are for an aqua-planet, a water covered Earth with no land, orography or sea-ice and with specified zonally symmetric SST. Simulations from 14 AGCMs developed for Numerical Weather Prediction and climate applications are compared. Four experiments are performed to study the sensitivity to the meridional SST profile. These profiles range from one in which the SST gradient continues to the equator to one which is flat approaching the equator, all with the same maximum SST at the equator.The zonal mean circulation of all models shows strong sensitivity to latitudinal distribution of SST. The Hadley circulation weakens and shifts poleward as the SST profile flattens in the tropics. One question of interest is the formation of a double versus a single ITCZ. There is a large variation between models of the strength of the ITCZ and where in the SST experiment sequence they transition from a single to double ITCZ. The SST profiles are defined such that as the equatorial SST gradient flattens, the maximum gradient increases and moves poleward. This leads to a weakening of the mid-latitude jet accompanied by a poleward shift of the jet core. Also considered are tropical wave activity and tropical precipitation frequency distributions. The details of each vary greatly between models, both with a given SST and in the response to the change in SST.One additional experiment is included to examine the sensitivity to an off-equatorial SST maximum. The upward branch of the Hadley circulation follows the SST maximum off the equator. The models that form a single precipitation maximum when the maximum SST is on the equator shift the precipitation maximum off equator and keep it centered over the SST maximum. Those that form a double with minimum on the equatorial maximum SST shift the double structure off the equator, keeping the minimum over the maximum SST. In both situations only modest changes appear in the shifted profile of zonal average precipitation. When the upward branch of the Hadley circulation moves into the hemisphere with SST maximum, the zonal average zonal, meridional and vertical winds all indicate that the Hadley cell in the other hemisphere dominates.METEOROLOGICAL SOC JAPAN, Sep. 2013, JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN, 91A, 57 - 89, English[Refereed]Scientific journal
- Climate simulations by 16 atmospheric general circulation models (AGCMs) are compared on an aqua-planet, a water-covered Earth with prescribed sea surface temperature varying only in latitude. The idealised configuration is designed to expose differences in the circulation simulated by different models. Basic features of the aqua-planet climate are characterised by comparison with Earth.The models display a wide range of behaviour. The balanced component of the tropospheric mean flow, and mid-latitude eddy covariances subject to budget constraints, vary relatively little among the models. In contrast, differences in damping in the dynamical core strongly influence transient eddy amplitudes. Historical uncertainty in modelled lower stratospheric temperatures persists in APE.Aspects of the circulation generated more directly by interactions between the resolved fluid dynamics and parameterized moist processes vary greatly. The tropical Hadley circulation forms either a single or double inter-tropical convergence zone (ITCZ) at the equator, with large variations in mean precipitation. The equatorial wave spectrum shows a wide range of precipitation intensity and propagation characteristics. Kelvin mode-like eastward propagation with remarkably constant phase speed dominates in most models. Westward propagation, less dispersive than the equatorial Rossby modes, dominates in a few models or occurs within an eastward propagating envelope in others. The mean structure of the ITCZ is related to precipitation variability, consistent with previous studies.The aqua-planet global energy balance is unknown but the models produce a surprisingly large range of top of atmosphere global net flux, dominated by differences in shortwave reflection by clouds. A number of newly developed models, not optimised for Earth climate, contribute to this. Possible reasons for differences in the optimised models are discussed.The aqua-planet configuration is intended as one component of an experimental hierarchy used to evaluate AGCMs. This comparison does suggest that the range of model behaviour could be better understood and reduced in conjunction with Earth climate simulations. Controlled experimentation is required to explore individual model behaviour and investigate convergence of the aqua-planet climate with increasing resolution.METEOROLOGICAL SOC JAPAN, Sep. 2013, JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN, 91A, 17 - 56, English[Refereed]Scientific journal
- 2013, Theoretical and Applied Mechanics, 61, 11 - 21, EnglishBaroclinic modes in the atmosphere on Venus simulated by AFES[Refereed]Scientific journal
- Differential Rotation and Angular Momentum Transport Caused by Thermal Convection in a Rotating Spherical ShellWe investigate generation mechanisms of differential rotation and angular momentum transport caused by Boussinesq thermal convection in a rotating spherical shell based on weakly nonlinear numerical calculations for various values of the Prandtl and Ekman numbers under a setup similar to the solar convection layer. When the Prandtl number is of order unity or less and the rotation rate of the system is small (the Ekman number is larger than O(10(-2))), the structure of thermal convection is not governed by the Taylor-Proudman theorem; banana-type convection cells emerge which follow the spherical shell boundaries rather than the rotation axis. Due to the Coriolis effect, the velocity field associated with those types of convection cells accompanies the Reynolds stress which transports angular momentum from high-latitudes to the equatorial region horizontally, and equatorial prograde flows are produced. The surface and internal distributions of differential rotation realized in this regime are quite similar to those observed in the Sun with helioseismology. These results may suggest that we should apply larger values of the eddy diffusivities than those believed so far when we use a low resolution numerical model for thermal convection in the solar interior.ASTRONOMICAL SOC PACIFIC, 2013, PROGRESS IN PHYSICS OF THE SUN AND STARS: A NEW ERA IN HELIO- AND ASTEROSEISMOLOGY, 479, 285 - 294, English[Refereed]International conference proceedings
- We examine the results of the Aqua-Planet Experiment Project (APE), focusing mainly on the structure of equatorial precipitation in the subset of participating models for which the details of model variables are available. Despite the unified setup of the APE, the Hovmöllor plots of precipitation in the models exhibit a considerable degree of diversity, presumably as a result of the diversity among the implementation of the various physical processes. Nevertheless, the wave number-frequency spectra of precipitation show certain similarities, and the power spectra can be divided into Kelvin, westward inertio-gravity, and "advective" components. The intensity of each of these three components varies significantly among different models. The composite spatial structures corresponding to these three components are produced by performing regression analysis with space-time filtered data. The composite horizontal structures of the Kelvin and westward inertio-gravity components are similar among the models, and resemble those expected from the corresponding equatorial shallow-water wave modes. These resemblances degrade at the altitude levels where the value of phase velocity approaches the zonal mean zonal wind speed. The horizontal structure of the advective component diverges significantly among the models. The composite vertical structures are strongly model dependent for all three components. The comparison of the vertical and horizontal structures associated with convective and stratiform heating of the composite disturbances indicates that the diversity of the vertical structures originates from differences in the implementation of the physical processes, especially the implementation of cumulus parameterization. © 2013, Meteorological Society of Japan.2013, Journal of the Meteorological Society of Japan, 91(1 A) (1 A), 91 - 141, English[Refereed]Scientific journal
- Nov. 2012, National Center for Atmospheric Research, English[Refereed]Scientific journal
- 2012, J, Meteor. Soc. Japan, 91A, 71 - 56The Aqua Planet Experiment (APE): Response to changed meridional SST profil[Refereed]Scientific journal
- Numerical Modeling for Venus Atmosphere Based on AFES (Atmospheric GCM for the Earth Simulator)In order to elucidate phenomena of Venus atmosphere, an atmospheric general circulation model (AGCM) for Venus is being developed on the basis of AFES (AGCM For the Earth Simulator). As a first step toward high resolution numerical simulation with realistic physical processes, we investigate unstable modes on the condition of super-rotation by nonlinear numerical simulation with simplified physical processes. At initial state zonal super-rotation is assumed to exist. We use the relaxation forcing of the meridional temperature gradient to maintain the zonal flow. In the time evolution of this experimental setting, baroclinic modes grow in the cloud layer with small static stability. The structures of unstable modes are similar to those obtained in the linear stability analysis. We discuss resolution dependency of the results.SPRINGER-VERLAG BERLIN, 2012, SYSTEM SIMULATION AND SCIENTIFIC COMPUTING, PT II, 327, 70 - +, English[Refereed]International conference proceedings
- Copernicus {GmbH}, 2012, Geosci. Model Dev., 5(2) (2), 449 - 455, English[Refereed]Scientific journal
- 2012, Nagare, Vol.31 (Nagare Multimedia 201, EnglishDependence of equatorial precipitation activity on the vertical profile of radiative cooling in an aqua-planet experiment[Refereed]Scientific journal
- Numerical experiments are performed in order to investigate an MHD dynamo in a rotating spherical shell with stress-free top and no-slip bottom boundaries. The Ekman number, the Prandtl number, and the ratio of inner to outer radii are fixed as 10(-3), 1, and 0.35, respectively. The magnetic Prandtl number is varied from 5 to 50, and the modified Rayleigh number is increased from 1.5 to 10 times the critical Rayleigh number. The initial imposed magnetic field is either a weak or strong magnetic field, where the magnetic energy of the initial field is approximately two orders of magnitude smaller or larger than the kinetic energy of the quasi-steady state of non-magnetic thermal convection. For cases involving a weak initial magnetic field, self-sustained dynamo solutions are established when the magnetic Prandtl number is larger than or equal to 5, and the modified Rayleigh number is larger than or equal to 5 times the critical Rayleigh number. The solutions are categorized as a weak field-dynamo, where the mean magnetic energy is one order of magnitude smaller than the mean kinetic energy. The dynamo solutions are characterized by a radially two-layer spatial structure. The upper layer is dominated by a strong prograde zonal mean zonal flow with large-scale prograde propagating spiral vortices having a longitudinal wavenumber of 3. Toroidal kinetic energy is converted to toroidal magnetic energy through stretching of the field lines by large-scale prograde propagating spiral vortices. On the other hand, the lower layer contains small-scale retrograde propagating columnar convective vortices having a longitudinal wavenumber of 8. The magnetic field lines are not concentrated in the vortices, but rather wind around the vortices in each layer. Poloidal kinetic energy is converted to poloidal magnetic energy through winding of the field lines around small-scale retrograde propagating columnar convective vortices. For cases involving a strong initial magnetic field, self-sustained dynamo solutions are established when the magnetic Prandtl number is greater than or equal to 4 and the modified Rayleigh number is greater than or equal to 3 times the critical Rayleigh number. In contrast with the cases involving a weak initial magnetic field, all of the dynamo solutions are strong-field solutions. Bistability is observed when the magnetic Prandtl number is 5, and the modified Rayleigh number is approximately equal to 10 times the critical Rayleigh number, where weak-field and strong-field dynamo solutions coexist. However, transition between the weak-field and strong-field solutions does not occur in this case. (C) 2011 Elsevier B.V. All rights reserved.ELSEVIER SCIENCE BV, Oct. 2011, PHYSICS OF THE EARTH AND PLANETARY INTERIORS, 188(3-4) (3-4), 203 - 213, English[Refereed]Scientific journal
- A long-term numerical simulation is performed to investigate idealized characteristics of the cloud layer of Jupiter's atmosphere using a two-dimensional cloud convection model that treats thermodynamics and microphysics of the three cloud components, H(2)O, NH(3), and NH(4)SH. A prominent result obtained is intermittent emergence of vigorous cumulonimbus clouds rising from the H(2)O condensation level to the tropopause. Due to the active transport associated with these clouds, the mean vertical distributions of cloud particles and condensible gases are distinctly different from the hitherto accepted three-layered structure; considerable amounts of H(2)O and NH(4)SH cloud particles exist above the NH(3) condensation level, while the mixing ratios of all condensible gases decrease with height from the H(2)O condensation level. The mean vertical profile of NH(3) vapor is consistent with the results of radio observations in that the abundance of NH(3) is subsolar below the NH(3) cloud base. Citation: Sugiyama, K., K. Nakajima, M. Odaka, M. Ishiwatari, K. Kuramoto, Y. Morikawa, S. Nishizawa, Y. O. Takahashi, and Y.-Y. Hayashi (2011), Intermittent cumulonimbus activity breaking the three-layer cloud structure of Jupiter, Geophys. Res. Lett., 38, L13201, doi: 10.1029/2011GL047878.AMER GEOPHYSICAL UNION, Jul. 2011, GEOPHYSICAL RESEARCH LETTERS, 38, L13201, English[Refereed]Scientific journal
- The Akatsuki spacecraft of Japan was launched on May 21, 2010. The spacecraft planned to enter a Venus-encircling near-equatorial orbit in December 7, 2010; however, the Venus orbit insertion maneuver has failed, and at present the spacecraft is orbiting the Sun. There is a possibility of conducting an orbit insertion maneuver again several years later. The main goal of the mission is to understand the Venusian atmospheric dynamics and cloud physics, with the explorations of the ground surface and the interplanetary dust also being the themes. The angular motion of the spacecraft is roughly synchronized with the zonal flow near the cloud base for roughly 20 hours centered at the apoapsis. Seen from this portion of the orbit, cloud features below the spacecraft continue to be observed over 20 hours, and thus the precise determination of atmospheric motions is possible. The onboard science instruments sense multiple height levels of the atmosphere to model the three-dimensional structure and dynamics. The lower clouds, the lower atmosphere and the surface are imaged by utilizing near-infrared windows. The cloud top structure is mapped by using scattered ultraviolet radiation and thermal infrared radiation. Lightning discharge is searched for by high speed sampling of lightning flashes. Night airglow is observed at visible wavelengths. Radio occultation complements the imaging observations principally by determining the vertical temperature structure.SPRINGER HEIDELBERG, 2011, EARTH PLANETS AND SPACE, 63(5) (5), 443 - 457, English[Refereed]Scientific journal
- Finite-amplitude thermal convection in a rapidly rotating spherical shell associated with a stably stratified layer placed near the outer surface is investigated. Systematic numerical experiments are performed with an Ekman number of E = 10-3, a Prandtl number of P = 1 and an inner/outer radius ratio of = 0.4, and the existence of a strongly stratified upper layer is shown to enhance the generation of equatorial surface retrograde flows when the Rayleigh number is approximately ten times larger than the critical value. The existence of the stable layer causes the bottom of the stable layer to behave as a virtual boundary for the convective motion underneath. Its effective dynamic condition varies from the free-slip condition to the no-slip condition as the Rayleigh number increases. The Reynolds stress of the convective vortices beneath the stable layer is weakened and is dominated by the transport of the planetary angular momentum. As a result, the latitudinal temperature gradient produced at the bottom of the stable layer induces the equatorial retrograde flow through the thermal wind balance. This diffuses through the stable layer by viscosity and produces the equatorial surface retrograde flow.TAYLOR & FRANCIS LTD, 2011, GEOPHYSICAL AND ASTROPHYSICAL FLUID DYNAMICS, 105(1) (1), 61 - 81, English[Refereed]Scientific journal
- Gfdnavi, Web-Based Data and Knowledge Server Software for Geophysical Fluid Sciences, Part I: Rationales, Stand-Alone Features, and Supporting Knowledge Documentation Linked to DataIn recent years, many data centers and research groups provide data on geophysical fluids such as the atmosphere and oceans through the Internet along with on-line visualization. However, their services are not available once data files are downloaded. This paper presents open-source software named Gfdnavi developed to reduce the limitation and to support data handling beyond initial "quick-looks". Gfdnavi extracts metadata from scientific data and stores them in a database. They can be accessed with web browsers for search, analysis, and visualization. It supports a wide range of usage such as public data services, group data management, and desktop use. As its unique feature, Gfdnavi supports writing and archiving documents based on knowledge obtained through-data analysis. The documents are linked with the original data and analysis/visualization procedures. It has a wide variety of applications such as interdisciplinary- and collaborative-study support, a realization of falsifiability, and educational use.SPRINGER-VERLAG BERLIN, 2010, DATABASE SYSTEMS FOR ADVANCED APPLICATIONS, 6193, 93 - +, English[Refereed]International conference proceedings
- Jet formation in decaying two-dimensional turbulence on a rotating sphere is reviewed from the view point of wave mean-flow interaction for both shallow-water case and non-divergent case as the limit of Fr (Froude number) going to zero. A series of computations have been performed by ourselves to confirm the behavior of zonal mean zonal flow generation on the parameter space of the non-dimensional rotation rate Omega and Fr. When the flow is non-divergent and Omega is large, intense retrograde circumpolar jets tend to emerge in addition to a banded structure of mean zonal flows with alternating flow directions in middle and low latitudes. As Fr increases, the circumpolar jets disappear and a retrograde jet emerges in the equatorial region. The appearance of the intense retrograde jets can be understood by the angular momentum transport associated with the propagation and absorption of Rossby waves. When the flow is non-divergent, long Rossby waves tend to be absorbed around the poles. In contrast, when Fr is large, Rossby waves can hardly propagate poleward and tend to be absorbed near the equator. The direction of the equatorial jet, however, is not always retrograde. Our ensemble experiments showed the emergence of a prograde jet, though less likely. This result is contrasted with the previous studies that reported retrograde equatorial jets in most cases for shallow-water turbulence. Furthermore, a mean zonal flow induced by wave-wave interactions was examined using a weakly nonlinear model to clarify the acceleration mechanisms of the equatorial jet. The second-order acceleration is induced by the Rossby waves and mixed Rossby-gravity waves and the acceleration mechanism can be categorized into two types.SPRINGER, 2010, IUTAM SYMPOSIUM ON TURBULENCE IN THE ATMOSPHERE AND OCEANS, 28, 253 - +, English[Refereed]International conference proceedings
- Development of a Numerical Model to investigate the Moist Convection in Jupiter's Atmosphere(Nagare-Multimedia)We develop a two-dimensional numerical fluid dynamical model that incorporates condensation of H_2O and NH_3 and the production reaction of NH_4SH in order to examine a vertical profile of multiple composition clouds and characteristics of convective motion in Jupiter's atmosphere. The basic equations of the model are based on the quasi-compressible system and the conservation equations of three condensible species in Jupiter's atmosphere. As a test run of the developed model, a long-time numerical simulation of moist convection with strong radiative cooling near the tropopause is performed...日本流体力学会, Aug. 2009, Journal of Japan Society of Fluid Mechanics, 28(4) (4), 357 - 358, Japanese[Refereed]
- Jan. 2009, (online journal), EnglishDevelopment of a Cloud Convection Model to Investigate the Jupiter's Atmosphere, Nagare Multimedia[Refereed]Scientific journal
- A series of numerical experiments on two-dimensional decaying turbulence is performed for a barotropic fluid on a rotating sphere. Numerical calculations have confirmed two important asymptotic features: emergence of the banded structure of zonal flows and their extreme latitudinal inhomogeneities in which kinetic energy is accumulated into the easterly circumpolar jets. The banded structure of zonal flows is established relatively early on in the initial stage. Later, after extended periods of time integration, only the circumpolar jets are intensified gradually, while there is no further evolution in the banded structure in the low and midlatitudes. Wave activity flux analysis illustrates that the initial vortices in the low and midlatitudes propagate poleward as Rossby waves and converge to produce easterly circumpolar flows. In association with this convergence, accumulation of the mean zonal component of kinetic energy proceeds. The tendency for the accumulation becomes strong as the rotation rate is increased, and nearly all of the kinetic energy is concentrated to the circumpolar flows in cases of rapid rotation. A theoretical model is constructed under the assumption that a circumpolar jet emerges around the latitude where the local Rhines scale is equal to the distance from the Pole, and that initial vortices at the lower latitudes contribute to the generation of the jets. The model describes the mean zonal component of kinetic energy and the averaged speed and width of the circumpolar jets as functions of the rotation rate, which agree satisfactorily with the numerical results.AMER METEOROLOGICAL SOC, Nov. 2007, JOURNAL OF THE ATMOSPHERIC SCIENCES, 64(11) (11), 4084 - 4097, English[Refereed]Scientific journal
- Multiple equilibrium solutions of a gray atmosphere are investigated for various values of the solar constant. Two types of models are utilized in order to conduct a comparative study: a general circulation model with simplified physical processes (GCM) and a one-dimensional energy balance model (EBM). For intermediate values of solar constant, both of the models indicate the existence of multiple solutions that include the runaway greenhouse state in addition to the globally ice-covered state and the partially ice-covered state. In the GCM results, there is no partially ice-covered state with the ice line latitude lower than 22 degrees. This indicates that the large ice cap instability discussed in previous EBM studies also occurs in GCM. Compared to the results of EBM, the ice line of the partially ice-covered state of GCM reaches lower latitudes. The appearance of the large ice cap instability in our GCM is impeded by condensation heating at the ice lines. The efficient latitudinal heat transport in the Hadley cell is considered to be a contributing factor to this delay in ice cap expansion.AMER GEOPHYSICAL UNION, Jul. 2007, JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 112(D13) (D13), English[Refereed]Scientific journal
- 2007, 電子情報通信学会第18回データ工学ワークショップ(DEWS2007)論文集, E1-8 (pp.8), Japanese[Refereed]Scientific journal
- American Meteorological Society, 2007, J. Atmos. Sci., 64(12) (12), 4246 - 4269, English[Refereed]Scientific journal
- A series of numerical experiments on two-dimensional decaying turbulence are performed for a non-divergent fluid on a rotating sphere, with attention focused on scaling properties of spontaneous circumpolar jets. The numerical calculations show that strong circumpolar westward (retrograde) jets emerge clearly in high latitudes at a large rotation rate Omega. A scaling theory is proposed for the jet width proportional to Omega(-1/4), and the jet strength to Omega(1/4) which agrees well with the numerical results. A noteworthy asymptotic feature is that kinetic energy is entirely concentrated on the circumpolar jets under large rotation rates. (c) 2006 The Japan Society of Fluid Mechanics and Elsevier B.V. All rights reserved.ELSEVIER SCIENCE BV, Jan. 2007, FLUID DYNAMICS RESEARCH, 39(1-3) (1-3), 209 - 220, English[Refereed]Scientific journal
- The dependency of static stability N-2 of the Jovian atmospheres on the abundances of condensible elements is considered by calculating the moist adiabatic profiles. An optimal minimization method of the Gibbs free energy is utilized to obtain equilibrium compositions in order to cover a variety of basic elements. It is shown that CH4 is one of the dominant contributors to producing a stable layer in the Uranian atmosphere. On Jupiter, R. K. Achterberg and A. P. Ingersoll (1989) have shown that, at low water abundances, N-2 is proportional to the H2O abundance. In the present study, we show that this relationship does not hold when the H2O abundance is larger than approximately 5 x solar. A rough estimation of wave speed indicates that the abundance of 10 x solar is marginal to explain the SL9-induced wave speed as that of an internal gravity wave.AMER GEOPHYSICAL UNION, Feb. 2006, GEOPHYSICAL RESEARCH LETTERS, 33(3) (3), English[Refereed]Scientific journal
- A series of spectral models which facilitate the execution of standard numerical experiments in geophysical fluid dynamics problems have been developed. Readability and modifiability of the program source codes are given priority in its design. The introduction of systematic function naming rules and the utilization of array-handling features enhanced by Fortran90 have permitted the program source codes to be written in a form that may be readily derived from the mathematical expressions of the original governing equations.The Japan Society of Fluid Mechanics, 2006, nagare, 25(5) (5), 485 - 486, Japanese
- An aqua planet experiment is performed to investigate the dependencies of the model representations of the equatorial precipitation activities on the horizontal and vertical resolution. The numerical model utilized is AFES, an AGCM optimized for the Earth Simulator. With the resolution of horizontal truncation at T39 and 48 vertical levels (referred to as the standard run), there appear precipitation disturbances of the scale of several grids, which are advected westward by the background wind. When the vertical resolution is increased to 96 levels from the standard run, precipitation tends to have weak intensity but be widely distributed, and the westward propagating grid-scale disturbances are rarely observed. When the horizontal resolution is increased to T319 from the standard run, a hierarchical structure appears. A large-scale eastward moving precipitation structure is superimposed on a small-scale westward moving structure.日本学術会議 「機械工学委員会・土木工学・建築学委員会合同IUTAM分科会」, Apr. 2005, NCTAM papers, National Congress of Theoretical and Applied Mechanics, Japan, 54(0) (0), 123 - 123
- METEOROLOGICAL SOC JPN, Apr. 2005, JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN, 83(2) (2), 270 - 270, English"Initial development of tropical precipitation patterns in response to a local warm SST area: An aqua-planet ensemble study" (vol 82, pg 1483, 2004)
- 2005, Theor. Appl. Mech. Japan, 54, 289 - 297, English[Refereed]Scientific journal
- For the purpose of examining the initial development of the atmospheric response to a warm SST anomaly placed at the equator, an ensemble switch-on experiment is conducted with an aqua-planet GCM. An ensemble average of the size of 128 significantly reduces the transient noises caused by both small scale convective activity and large scale intraseasonal variability. In the first three days after the switch-on of the SST anomaly, a convection center develops above the warm SST area. As a barotropic response to the heating of convection center, a global increase of surface pressure occurs outside the low pressure region around the warm SST area. The response after the emergence of the high pressure anomaly is consistent with Gill (1980); a warm Kelvin wave-like anomaly is emitted to the east of the convection center, while a warm Rossby wave-like anomaly is emitted to the west. The Kelvin wave-like signal propagates at a speed slower than that of free Kelvin wave expected from its vertical wavelength, suggesting that the signal is a "moist" Kelvin wave. Transient decrease of precipitation occurs at the moist Kelvin wave front; a decrease of convection associated with the downward motion at the wave front is consistent with its slow propagation. After several days, precipitation recovers and is even intensified because of the surface frictional convergence associated with the Kelvin wave-like equatorial low pressure anomaly. To the west of the warm SST area, on the other hand, precipitation decreases monotonically. The continuous reduction of precipitation is caused by the equatorial surface frictional divergence associated with the relatively high pressure anomaly at the equator of the Rossby wave structure. Finally, there appears a slow zonally symmetric response within the Hadley cell characterized with surface pressure rise in the tropics and westerly wind anomaly in the troposphere. The change of eddy zonal momentum transport, together with the transport toward the lower level by the Hadley circulation and the geostrophic adjustment to the resulting low level westerly acceleration, seems to be responsible for the response.METEOROLOGICAL SOC JPN, Dec. 2004, JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN, 82(6) (6), 1483 - 1504, EnglishScientific journal
- 2003, J. Geophys. Res, 108(E3) (E3), 5018-doi: 10.1029/2001JE001638Topographically induced north-south asymmetry of the meridional circulation in the Martian atmosphere
- A numerical study on the runaway greenhouse state is performed by using a general circulation model (GCM) with simplified hydrologic and radiative processes. Except for the inclusion of three-dimensional atmospheric motion, the system utilized is basically equivalent to the one-dimensional radiative-convective equilibrium model of Nakajima et al, in which the runaway greenhouse state is defined. The results of integrations with various values of solar constant show that there exists an upper limit of the solar constant with which the atmosphere can reach a statistical equilibrium state. When the value of solar constant exceeds the limit, 1600 W m-2, the atmosphere sets in a "thermally runaway" state. It is characterized by continuous increase of the amount of water vapor, continuous decrease of the outgoing longwave radiation, and continuous warming of the atmosphere and the ground surface. The upper-limit value of the solar constant obtained by the GCM experiments corresponds to the upper limit of outgoing longwave radiation determined by the one-dimensional model of Nakajima et al, with a fixed value of relative humidity, 60%, which is a typical value obtained by the GCM. The thermally runaway states realized in the GCM are caused by the radiation structure found by Nakajima et al. that prohibits the existence of thermal equilibrium states. The calculated values of the upper limit of radiation and water vapor content cannot be directly applied to describing real planetary atmospheres, since the model physical processes are quite simple-gray radiation scheme without clouds. However, because of this simplification, the GCM gives deeper insight into the structure of a runaway atmosphere.American Meteorological Society, Nov. 2002, Journal of the Atmospheric Sciences, 59(22) (22), 3223 - 3238, English[Refereed]Scientific journal
- AMER METEOROLOGICAL SOCIETY, 2002, 18TH INTERNATIONAL CONFERENCE ON INTERACTIVE INFORMATION AND PROCESSING SYSTEMS (IIPS) FOR METEOROLOGY, OCEANOGRAPHY, AND HYDROLOGY, 220 - 221, EnglishDevelopment of GTOOL4 netCDF conventions and processor self descriptive file format for multi-dimensional data[Refereed]International conference proceedings
- 2002, "Statistical Theories and Computational Approaches to Turbulence" Y. Kaneda and T. Gotoh Eds., Springer-Verlag, Tokyo, 317-326, EnglishPattern formation in two-dimensional turbulence on a rotating sphere[Refereed]
- Linear stability of rotating thermal convection in a horizontal layer of Boussinesq fluid under the fixed heat flux boundary condition is examined by the use of a vertically truncated system up to wavenumber one. When the rotation axis is in the vertical direction, the asymptotic behavior of the critical convection for large rotation rates is almost the same as that under the fixed temperature boundary condition. However, when the rotation axis is horizontal and the lateral boundaries are inclined, the mode with zero horizontal wavenumber remains as the critical mode regardless of the rotation rate. The neutral curve has another local minimum at a nonzero horizontal wavenumber, whose asymptotic behavior coincides with the critical mode under the fixed temperature condition. The difference of the critical horizontal wavenumber between those two geometries is qualitatively understood by the difference of wave characteristics; inertial waves and Rossby waves, respectively.TAYLOR & FRANCIS LTD, 2002, GEOPHYSICAL AND ASTROPHYSICAL FLUID DYNAMICS, 96(6) (6), 439 - 459, English[Refereed]Scientific journal
- Dec. 2001, ながれ : 日本流体力学会誌, 20(6) (6), 507 - 508, Japanese
- 2001, Nagare, 19(4) (4)A numerical simulation of thermal convection in the Martian lower atmosphere with a two-dimensional anelastic model(jointly worked)[Refereed]
- Moist convection of Jupiter's atmosphere is examined using a large-domain two-dimensional fluid dynamical model with simplified cloud microphysics of water. The result shows that the water condensation level acts as a dynamical and compositional boundary. The convection below the condensation level is characterized by a steady regular cellular structure and a homogeneous distribution of water mixing ratio. Above the condensation level, cloud elements accompanied by the upward motion develop and disappear irregularly but successively, and water mixing ratio is highly inhomogeneous. The horizontal average of mixing ratio decreases rapidly with height just above the condensation level, resulting in a distinctive stable layer at 5 bar. The stable layer prevents the air masses above and below it from mixing with each other. As a result, the upper dry air does not reach 20 bar level, where the Galileo probe observed low humidity.AMER GEOPHYSICAL UNION, Oct. 2000, GEOPHYSICAL RESEARCH LETTERS, 27(19) (19), 3129 - 3132, English[Refereed]Scientific journal
- Technical approach for the design of a high-resolution spectral model on a sphere: Application to decaying turbulenceSeveral technical suggestions to construct a high-resolution spectral model on a sphere (the T682 barotropic model) are presented and their implementation in FORTRAN77 libraries is provided as a free software package ISPACK (http://www.gfd-dennou.org/arch/ispack/). A test experiment on decaying turbulence is conducted to demonstrate the ability of the model.EUROPEAN GEOPHYSICAL SOCIETY, Mar. 2000, NONLINEAR PROCESSES IN GEOPHYSICS, 7(1-2) (1-2), 105 - 110, English[Refereed]Scientific journal
- 2000, Proceedings of the IUTAM Symposium on Developments in Geophysical Turbulence(Fluid Mecahnics and Its Applications Vol.58), R.M. Kerr and Y. Kimura Eds., Kluwer Academic Pub., 179-192, EnglishEmergence of circumpolar vortex in two dimensional turbulence on a rotating sphere[Refereed]
- Dec. 1999, ながれ : 日本流体力学会誌, 18(6) (6), 414 - 415, Japanese
- Nov. 1999, Nuovo Cimento della Societa Italiana di Fisica C, 22(6) (6), 803 - 812, EnglishA further experiment on two-dimensional decaying turbulence on a rotating sphere[Refereed]
- AMER METEOROLOGICAL SOCIETY, 1999, 12TH CONFERENCE ON ATMOSPHERIC AND OCEANIC FLUID DYNAMICS, 296 - 297, EnglishTwo-dimensional turbulence on a rotating sphere with high-resolution spectral model[Refereed]International conference proceedings
- Mean zonal flows excited by critical modes of Boussinesq convection in rotating spherical shells are evaluated systematically by the weak nonlinear method. Calculations are executed in the ranges of the Prandtl number 0.01 less than or equal to P less than or equal to 10(2), the Taylor number 10 degrees less than or equal to T less than or equal to 10(7), and the radius ratio 0.2 less than or equal to eta less than or equal to 0.8. In the case of small rotation rates, two new states of zonal flow at the equatorial outer boundary are obtained; westerly flow emerges even when the Prandtl number is large, and easterly flow emerges even when the Prandtl number is small. The latter case is interesting since the induced equatorial easterly is in the opposite direction to that of the acceleration. In the case of large rotation rates, it is confirmed that the direction of mean zonal flow at the equatorial outer boundary does not depend on the thickness of the shell.TAYLOR & FRANCIS LTD, 1999, GEOPHYSICAL AND ASTROPHYSICAL FLUID DYNAMICS, 90(1-2) (1-2), 43 - 77, English[Refereed]Scientific journal
- Pattern Formation from Two-dimensional Decaying Turbulence on a Rotating Sphere.Time-evolutions of decaying turbulence in two-dimensional non-divergent fluid on a rotating sphere were conducted with high-resolution numerical model to examine what stream pattern appears finally.<BR>To investigate the condition needed for each pattern to appear in detail, higher-resolution model are used and wider parameter range of initial condition or angular velocity of sphere rotation are swept than other past researches on the same subject.<BR>As a result, it is confirmed that the appearance of easterly polar vortex when the angular velocity of sphere rotation is rapid is a robust feature. Furthermore, it turned out to be necessary for band structure of zonal flow to appear in middle and low latitudes that initial energy must be injected into small scale enough as well as the angular velocity of sphere rotation is rapid.The Japan Society of Fluid Mechanics, 1999, Journal of Japan Society of Fluid Mechanics, 18(6) (6), 410 - 411, Japanese
- 1999, Theoretical and Applied Mechanics, 48, 415, EnglishThe Effects of thermal boundary condition on convection in rapidly rotating spherical shells[Refereed]Scientific journal
- 京都大学, Jan. 1999, 数理解析研究所講究録, 1075, 85 - 100, Japanese熱フラックス固定境界条件での回転系の熱対流 (回転流の数理)
- Nov. 1998, Proc ISAS Lunar Planet Symp (Inst Space Astronaut Sci), 31st, 34 - 37, EnglishEmergence of circumpolar vortex in 2-D turbulence on a rotating sphere.[Refereed]
- Aqua planet experiments are performed in order to investigate the effects of an equatorial warm sea surface temperature (SST) area on the tropical large-scale precipitation patterns. The numerical model utilized is a spherical three-dimensional primitive system with resolution of T42L16 and with simplified hydrological processes. The warm SST area is placed at the equator of an aqua planet whose basic SST distribution is zonally uniform and symmetric about the equator. The calculated tropical precipitation distributions are characterized by the appearance of an east-west asymmetry; precipitation decreases to the west of the warm SST area, while it increases in the longitudinally wide area to the east. The east-west asymmetry appears regardless of the cumulus parameterization schemes utilized (the convective adjustment scheme and the Kuo scheme). In the western region to the warm SST area, an increase of the stability due to a temperature rise in the middle layer is observed and correspondingly downward flow is recognized. These are consistent with the decrease of precipitation. In the eastern region, although a temperature rise appears in the middle layer, the stability decreases due to the increase of water vapor in the lower layer caused by the meridional moisture convergence. This destabilization is consistent with the increase of precipitation. Experiments in which the wind velocity used in the evaluation of the surface evaporation is fixed are performed to show that WISHE (Wind Induced Surface Heat Exchange) mechanism is not a principal cause for the generation of the east-west asymmetry of the precipitation pattern.METEOROLOGICAL SOC JAPAN, Apr. 1998, JOURNAL OF THE METEOROLOGICAL SOCIETY OF JAPAN, 76(2) (2), 289 - 305, English[Refereed]Scientific journal
- 1998, Nagare Multimedia, English[Refereed]Scientific journal
- Thermal convection of the Martian lower atmosphere is examined by the use of a two-dimensional anelastic model with a resolution fine enough to describe convection eddies. For a homogeneous radiative cooling of 50 K/day given in the layer below 5 km, a layer of time-dependent convection develops up to about 6 km in height. The intensity of realized vertical winds ranges up to 20 m/s. The dust, which is injected into the lowest layer and treated as a passive tracer, is transported immediately in the convection layer and mixed uniformly. The intensity of the horizontal winds near the surface reaches about 10 m/s, which, combined with large-scale motions, is expected to contribute to the dust injection into the atmosphere.TERRA SCIENTIFIC PUBL CO, 1998, EARTH PLANETS AND SPACE, 50(5) (5), 431 - 437, English[Refereed]Scientific journal
- 京都大学, Oct. 1996, 数理解析研究所講究録, 970, 105 - 114, Japanese暴走温室状態の長時間積分(熱対流の数理)
- The effects of thermal conditions on the patterns of two-dimensional Boussinesq convection are studied by numerical integration. The adopted thermal conditions are (i) the heat fluxes through both upper and lower boundaries are fixed, (ii) the same as (i) but with internal cooling, (iii) the temperature on the lower boundary and the heat flux through the upper boundary are fixed, (iv) the same as (iii) but with internal cooling, and (v) the temperatures on both upper and lower boundaries are fixed. The numerical integrations are performed with Ra = 104 and Pr = 1 over the region whose horizontal and vertical lengths are 8 and 1, respectively. The results confirm that convective cells with the larger horizontal sizes tend to form under the conditions where the temperature is not fixed on any boundaries. Regardless of the existence of internal cooling, one pair of cells spreading all over the region forms in the equilibrium states. On the other hand, three pairs of cells form and remain when the temperature on at least one boundary is fixed. The formation of single pairs of cells appearing under the fixed heat flux conditions shows different features with and without internal cooling. The difference emerges as the appearance of a phase change, whose existence can be suggested by the weak nonlinear equation derived by Chapman & Proctor (1980).Cambridge University Press (CUP), Dec. 1994, Journal of Fluid Mechanics, 281, 33 - 50, English[Refereed]Scientific journal
- American Meteorological Society, Dec. 1992, Journal of the Atmospheric Sciences, 49(23) (23), 2256 - 2266Scientific journal
- American Meteorological Society, Jul. 1992, Journal of the Atmospheric Sciences, 49(14) (14), 1202 - 1220[Refereed]Scientific journal
- The characteristics of shallow-water waves in a linear shear flow are studied, and the relationship between waves and unstable modes is examined. Numerical integration of the linear shallow-water equations shows that over-reflection occurs when a wave packet is incident at the turning surface. This phenomenon can be explained by the conservation of momentum as discussed by Acheson (1976). The unstable modes of linear shear flow in a shallow water found by Satomura (1981) are described in terms of the properties of wave propagation as proposed by Lindzen and others. Ripas's (1983) theorem, which is the sufficient condition for stability of flows in shallow water, is also related to the wave geometry. The Orr mechanism, which is proposed by Lindzen (1988) as the primary mechanism of wave amplification, cannot explain the over-reflection of shallow-water waves. The amplification of these waves occurs in the opposite sense to that of Orr's solution.Cambridge University Press (CUP), Mar. 1992, Journal of Fluid Mechanics, 236, 259 - 279[Refereed]Scientific journal
- Meteorological Society of Japan, 1991, Journal of the Meteorological Society of Japan. Ser. II, 69(5) (5), 563 - 579[Refereed]Scientific journal
- Meteorological Society of Japan, 1991, Journal of the Meteorological Society of Japan. Ser. II, 69(5) (5), 541 - 561[Refereed]Scientific journal
- American Meteorological Society, Jan. 1989, Monthly Weather Review, 117(1) (1), 236 - 243[Refereed]Scientific journal
- This article considers the instabilities of rotating, shallow-water, shear flows on an equatorial β-plane. Because of the free surface, the motion is horizontally divergent and the energy density is cubic in the field variables (i.e. in standard notation the kinetic energy density is ½ h(u2 + v2)). Marinone & Ripa (1984) observed that as a consequence of this the wave energy is no longer positive definite (there is a cross-term Uh′u′). A wave with negative wave energy can grow by transferring energy to the mean flow. Of course total (mean plus wave) energy is conserved in this process. Further, when the basic state has constant potential vorticity, we show that there are no exchanges of energy and momentum between a growing wave and the mean flow. Consequently when the basic state has no potential vorticity gradients an unstable wave has zero wave energy and the mean flow is modified so that its energy is unchanged. This result strikingly shows that energy and momentum exchanges between a growing wave and the mean flow are not generally characteristic of, or essential to, instability. A useful conceptual tool in understanding these counterintuitive results is that of disturbance energy (or pseudoenergy) of a shear mode. This is the amount of energy in the fluid when the mode is excited minus the amount in the unperturbed medium. Equivalently, the disturbance energy is the sum of the wave energy and that in the modified mean flow. The disturbance momentum (or pseudomomentum) is defined analogously. For an unstable mode, which grows without external sources, the disturbance energy must be zero. On the other hand the wave energy may increase to plus infinity, remain zero, or decrease to minus infinity. Thus there is a tripartite classification of instabilities. We suggest that one common feature in all three cases is that the unstable shear mode is roughly a linear combination of resonating shear modes each of which would be stable if the other were somehow suppressed. The two resonating constituents must have opposite-signed disturbance energies in order that the unstable alliance has zero disturbance energy. The instability is a transfer of disturbance energy from the member with negative disturbance energy to the one with positive disturbance energy.Cambridge University Press (CUP), Nov. 1987, Journal of Fluid Mechanics, 184, 477 - 504[Refereed]Scientific journal
- Meteorological Society of Japan, 1986, Journal of the Meteorological Society of Japan. Ser. II, 64(4) (4), 451 - 467[Refereed]Scientific journal
- 1984, Dynamics of the Middle Atmosphere, Proceedings of a Seminar held 8-12 November, 1982 in Honolulu, Hawaii. Edited by J.R. Holton and T. Matsuno. Tokyo, Japan: Terra Scientific Publishing Company, 1984., 141 - 160Internal gravity wave enhancement by the chemical heat release due to oxygen recombination[Refereed]International conference proceedings
- Meteorological Society of Japan, 1984, Journal of the Meteorological Society of Japan. Ser. II, 62(3) (3), 377 - 387, Japanese[Refereed]Scientific journal
- May 2022, 科学, 92(5) (5), 432 - 436, Japanese電子計算機が拓いた理論的気象気候研究—特集 気候シミュレーションの展開
- 朝日新聞社, Dec. 2021, 論座, Japanese, Domestic magazineIntroduction commerce magazine
- 朝日新聞社, Dec. 2021, 論座, JapaneseIntroduction commerce magazine
- 2021, 日本気象学会大会講演予稿集(CD-ROM), (120) (120)金星大気の放射計算と放射対流平衡実験
- 2021, 宇宙航空研究開発機構研究開発報告 JAXA-RR-(Web), (20-010) (20-010)A study on visualization for huge numerical simulation data of planetary atmospheres using web map technology
- 小宮山印刷工業, Jun. 2020, シミュレーション = Journal of the Japan Society for Simulation Technology / 日本シミュレーション学会 編, 39(2) (2), 85 - 93, Japanese惑星内部・表層のダイナミクスと進化: ショウトクシュウ ポスト 「 キョウ 」 ホウガテキ カダイ 「 セイメイ オ ハグクム ワクセイ ノ キゲン ・ シンカ ト ワクセイ カンキョウ ヘンドウ ノ カイメイ 」
- 2019, 日本天文学会年会講演予稿集, 2019大気大循環モデルを用いた系外惑星の光度曲線解析による自転軸傾斜角推定 II
- 金星大気の全球的な流れを計算する数値モデル「AFES-Venus」とそれを用いた数値実験・データ同化について紹介する．AFES-Venusは，金星大気の惑星規模筋状構造や周極低温域，大気安定度の地方時依存性などの再現に成功している．AFES-Venusでは，高度55 km付近に低安定度層を導入したことと，空間解像度を高めたことによって，傾圧不安定の発達が計算されるようになった．数値実験により，傾圧不安定の発達が，金星大気の現実的な風速・温度場の再現にとって重要であることが分かってきた．また我々は，AFES-Venusを用いたデータ同化システムも開発しており，「あかつき」による観測を反映した現実的かつ時空間的に偏りのない金星大気のデータセットの創出や，個々の観測の重要度評価による観測計画立案への貢献も目指している．The Japanese Society for Planetary Sciences, 25 Dec. 2018, Planetary People - The Japanese Society for Planetary Sciences, 27(4) (4), 314 - 319, Japanese
- 丸善出版, Feb. 2017, パリティ = Parity : 物理科学雑誌, 32(2) (2), 42 - 50, Japanese温暖化問題,討論のすすめ 気候変化の影響,その理解の深化発展—Climate change impacts : The growth of understanding
- Center for Earth Information Science and Technology, Japan Agency for Marine-Earth Science and Technology, Apr. 2016, Annual report of the earth simulator, 31 - 36, JapaneseHigh Resolution General Circulation Simulation of Venus and Mars Atmosphere Using AFES
- Center for Earth Information Science and Technology, Japan Agency for Marine-Earth Science and Technology, Apr. 2015, Annual report of the earth simulator, 31 - 38, EnglishSimulations of Atmospheric General Circulations of Earth-like Planets by AFES
- 2015, 日本惑星科学会秋季講演会予稿集(Web), 2015放射対流平衡モデルによる水蒸気大気の圏界面温度の推定
- AMER METEOROLOGICAL SOC, Jul. 2014, BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY, 95(7) (7), 1101 - 1104, English[Refereed]Others
- A round table talk on solar system exploration with Mizutani-san2013年9月17日から20日まで,北海道ニセコ町で惑星科学フロンティアセミナー2013(主催・惑星科学フロンティアセミナー実行委員会)が開催されました.この中で,講師に迎えた独立行政法人宇宙航空研究開発機構(JAXA)の宇宙科学研究所(ISAS)名誉教授で科学雑誌Newton編集長の水谷仁氏を囲んで,ISAS在任中の思い出を語り合う座談会が企画されました.月探査機LUNAR-A計画の狙いに始まり,宇宙科学研究をどのように展開すればよいのか研究手法にも話題が及び,さらには惑星科学コミュニティーが中心となって次なる惑星科学の研究テーマをどう見出すべきなのかといった内容が話し合われました.以下,座談会で行われた主なやり取りを紹介します.(敬称略)日本惑星科学会, Jun. 2014, Planetary People, 23(2) (2), 120 - 129, Japanese
- Researches on planetary atmospheres using numerical models and GFD-Dennou Club DCMODEL projectSpace missions for planetary atmospheres and numerical simulations are fundamental components for researches on planetary atmospheres. Recently, numerical simulation models become essential to planning of missions, analyzing and providing observational data. On the other hand, the simulation models used in these researches have become so expanded and complicated that it is dif.cult for one researcher to understand, develop, maintain and provide their source codes. "Model gap problem"is one of the dif.culties with numerical simulation models. In order to check the validity of the simulation models and to develop them further, it is necessary to perform numerical calculations with numerical models with various complexities and to compare the numerical results mutually. Expansion of the simulation models makes dif.cult to perform such inter-comparison for checking of the validity. In an attempt to overcome the "model gap problem", we have been proceeding"dcmodel project", where a series of hierarchical numerical models with various complexity is developed and maintained as a voluntary activity. The numerical models are developed with the following intentions: 1) Hierarchical models with various complexities. 2) Common"style" of programming in order to ensure readability. 3) Open source codes to the public. 4) Scalability of the models in order to ensure execution on various platforms. 5) Stressing the importance of documentation and presenting a method for producing reference manuals. The series of hierarchical models enable us to conduct multiple numerical experiments with multiple models easily, which will lead to a deeper understanding of various phenomena in planetary atmospheres.Japan Aerospace Exploration Agency, Mar. 2014, JAXA research and development report, 13, 147 - 153, Japanese
- The Japanese Society for Planetary Sciences, Mar. 2014, Planetary People, 23(1) (1), 64 - 69, JapaneseSymposium on Computational Planetary Science
- 2014, 宇宙科学情報解析論文誌, 3, 147 - 153, Japanese地球流体電脳倶楽部 DCMODELプロジェクトと数値モデルを用いた惑星大気研究について[Refereed]
- Earth Simulator Center, Japan Agency for Marine-Earth Science and Technology, Apr. 2013, Annual report of the Earth Simulator Center, 31 - 37, EnglishSimulations of Atmospheric General Circulations of Earth-like Planets by AFES
- Circulations of atmosphere of synchronously rotating planets, which have perpetual dayside and nightside, are investigated by using a general circulation model with simplified hydrological processes.Results of experiments with various planetary rotation rate and solar constant show that the upper limit of solar constant with which equilibrium states are maintained is almost independent of rotation rate. The upper limit is determined by the radiation limit.In cases where equilibrium states are obtained, the amount of day-night energy transport is independent of rotation rate and determined by the difference between dayside mean insolation flux and radiation limit, although circulation changes.National Committee for IUTAM, 2013, NCTAM papers, National Congress of Theoretical and Applied Mechanics, Japan, 62(0) (0), Japanese
- A repository for knowledge of planetary science served by Center for Planetary Science (CPS)惑星科学研究センター(CPS)では,国内外の惑星科学研究者の教育研究活動を広く支援する「場」の1つとして,先端的な知見の共有を容易にするための知見アーカイブを構築している.この取り組みは, 2000年に発足した北海道大学理学部の有志活動であるmosirプロジェクトを継承・発展させたものであり,現在に至るまでの活動で蓄積した研究会やセミナーでの研究発表を始めとするコンテンツは1,100本以上にのぼる.本稿ではCPSの知見アーカイブの概要を示すと共に,知見アーカイブの利便性を向上させるための取り組みや作業コストの低減を図るための取り組みを解説する.The Japanese Society for Planetary Sciences, 25 Dec. 2012, Planetary People, 21(4) (4), 368 - 376, Japanese
- 光の透過性の問題で,木星雲層の大気構造の観測は断片的・間接的にならざるを得ず,その構造は未だよくわかっていない.1970年代に,鉛直1次元の平衡雲凝結モデルによって大気構造が理論的に調べられ,組成の異なる3成分の雲が別々の高度に分かれて存在するという描像が作られた.この描像は,一般的に受け入れられているが,大気の運動や降水等の雲微物理過程によって変化するはずである.筆者らはH_2OとNH_3の凝結とNH_4SHの生成反応を考慮した雲解像モデルを開発し,多数の雲の生成消滅が繰り返された結果として決まる大気構造を調べてきた.本稿ではこれまでの木星雲層の大気構造の認識を概観しつつ,筆者らの最近の研究結果を紹介する.日本惑星科学会, 25 Mar. 2012, Planetary People, 21(1) (1), 39 - 44, Japanese
- 2012, 天気, 59(9) (9), 859 - 860, Japanese6. 波と平均流の相互作用(2012年度春季大会専門分科会報告,研究会報告)
- 2012, 遊星人, Vol.21, 368--376(103) (103), Japanese惑星科学研究センター（CPS）における知見アーカイブ[Refereed]
- 2012, 遊星人, 21, 39—44, Japanese木星の大気構造と雲対流[Refereed]
- 2012, Proceedings of International Conference on Simulation Technology, ID73, EnglishToward high resolution simulation for theatmosphere on Venus by AFES (Atmospheric GCM For the Earth Simulator)[Refereed]
- 2012, Proceedings of Inernational Conference on Simulation and Technology, JSST, EnglishSurface zonal flow induced by turbulent convection in rapidly rotating spherical shells[Refereed]
- 2012, Proceedings of Inernational Conference on Simulation and Technology, JSST, EnglishConstruction of Hierarchical Models for the Fluid Dynamics in Earth and Planetary Sciences : DCMODEL project[Refereed]
- Jan. 2011, 第 11 回惑星圏研究会収録, 1,1-4, Japanese高解像度火星大気大循環モデルで見られる中小規模擾乱
- The effects of the upper mechanical boundary condition on MHD dynamo solutions in a rotating spherical shellNumerical experiments of magnetohydrodynamic (MHD) dynamos driven by thermal convection in a rotating spherical shell with a free-slip top boundary and a no-slip bottom boundary are performed. The Ekman number, the Prandtl number and the ratio of inner and outer radii are fixed to 10^<-3>, 1, and 0.35, respectively. The magnetic Prandtl number Pm is varied from 1 to 50. The modified Rayleigh number Ra is increased up to 15 times the critical value Ra_c. MHD calculations are carried out from non-magnetic thermal convection solutions with a weak dipole magnetic field on top of them, and dynamo solutions are obtained when Ra≥1.87Ra_c and Pm≥4. The strong prograde zonal flows in the non-magnetic solutions disappear in the dynamo solutions as the evolution of magnetic fields, and slow retrograde zonal flows emerge at the top of the spherical shell. As a result, the omega effect which was expected from the strong zonal flows of the non-magnetic solutions does not operate effectively. All of the obtained dynamo solutions are considered to be categorized as the α^2-type dynamo.日本流体力学会, Sep. 2009, ながれ(日本流体力学会学会誌), 2009, 106 - 106, Japanese
- 日本天文学会, 20 Feb. 2009, 天文月報, 102(3) (3), 184 - 189, Japaneseハビタブル惑星の起源, 進化, 多様性
- We develop a three dimensional non-hydrostatic model and perform a numerical simulation of thermal convection in the Martian atmosphere without background wind and dust radiative heating. The numerical model based on the two dimensional quasi-compressible model developed by Sugiyama et al. (2008). The atmospheric radiative transfer is not calculated explicitly, and a horizontally uniform body cooling is introduced below 5km height. After 12 hours of integration, the thermal convection whose horizontal scale of updraft region is several km is developed. The upward wind velocity reaches from 10 to 15m/sec while the downward wind velocity is about several m/sec. At the lowest level of the three dimensional model (z=50m), isolated vertical vortexes which horizontal scale is about several hundred m are developed frequently. This result suggests that the vertical vortex like dust devils may be naturally developed accompanied with the convective motion without background wind.Japan Society of Fluid Mechanics, 04 Sep. 2008, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2008, 378 - 378, Japanese
- Retrograde equatorial surface flows generated by thermal convection under a stably stratified layer in a rotaiting spherical shellFinite amplitude thermal convection in a rapidly rotating spherical shell associated with a stably stratified layer forced near the outer surface is investigated. Systematic numerical experiments are performed with the Ekman number E=10^3, the Prandtl number P=1 and the inner/outer radius ratio η=0.4, and show that existence of a strongly stratified upper layer enhances generation of equatorial retrograde flows when the Rayleigh number is ten times larger than the critical value. Although the convective flows become turbulent and do not form regular Taylor-column type vortices in the deep region, they still cannot erode the stably stratified layer. The effect of the stratified layer is to introduce a virtual boundary between the stable and convective layers, which is subject to an intermediate dynamical condition between the no-slip and the free-slip and actually increases the inner/outer radius ratio.日本流体力学会, 2008, 日本流体力学会年会講演論文集, 2008, 375 - 375, Japanese
- MHD dynamo in a rotating spherical shell: Influence of mechanical boundary conditionsNumerical experiments of magnetohydrodynamic dynamos driven by thermal convection in a rotating spherical shell with a free-slip top boundary and a no-slip bottom boundary are performed. Non-dimensional numbers for the experiments are the modified Rayleigh number Ra=100, the Ekman number E=10^<-3>, the Prandtl number Pr=1, the ratio of inner and outer radii ξ=0.35. The magnetic Prandtl number Pm is varied from 5 to 50. Time integration of non-magnetic thermal convection is carried out until a quasi-steady state is established, and then MHD dynamo calculation is carried out starting from the quasi-steady state with a dipole and toroidal magnetic field. In the non-magnetic thermal convection case, the obtained solution consists of well-organized spiral vortex columns aligned with the rotation axis. A strong prograde zonal flow is produced at the top of the spherical shell in contrast to the simulations with the both no-slip boundaries. In the MHD dynamo cases, calculated magnetic fields fall into decay at all magnetic Prandtl numbers. The strong prograde zonal flow, which is prominent in the case of non-magnetic thermal convection, does not appear, but a slow retrograde zonal flow is produced at the top of spherical shell. As a result, the omega effect expected from the strong zonal flows does not seem to operate effectively.日本流体力学会, 2008, 日本流体力学会年会講演論文集, 2008, 376 - 376, Japanese
- Dust lifting process represented by a high resolution Mars general circulation modelIn order to investigate the effects of small and medium scale atmospheric circulation and disturbances on dust lifting process on Mars, the high resolution simulations of the Martian atmosphere are performed by using a Mars general circulation model. The simulations with horizontal resolutions of 89, 44, and 22km show that the dust lifting amount increases with increasing resolution. The increase of dust lifting amount is mainly caused by the lifting around several regions with characteristic orographic features, such as the Valles Marineris and the Hellas basin. The analysis of dust lifting phenomena in the Valles Marineris region shows that the superposition of local slope wind and the return flow of meridional circulation causes the large dust lifting in the region. This implies that the effects of small and medium scale local orographic circulation play an important role in lifting dust on Mars.日本流体力学会, 2008, 日本流体力学会年会講演論文集, 2008, 379 - 379, Japanese
- 2008, 研究集会報告, 19ME-S6,, Japanese木星大気の雲対流の直接数値計算, 第９回地球流体力学研究集会「地球流体における波動と対流現象の力学」[Refereed]
- Jan. 2008, 遊星人(日本惑星科学会学会誌), 17,, Japanese広帯域ネットワークを基盤とした大学と公開天文台との連携,[Refereed]
- A numerical experiment of a moist planet with a general circulation modelAiming for constructing an atmospheric general circulation model (GCM) with high readability and flexibility, desired program structures have been considered and their implementation tests have been performed. A flexible GCM whose programs can be easily changed is useful for investigating the structures of various planetary atmospheres from the viewpoint of comparative planetary science. In order to consider moist atmospheric circulations such as Earth and Jupiter, we have performed following attempts for facilitating exchanges of physical processes; (1) a design of physical process modules, (2) a development of a library for the production of test programs, (3) an improvement of document auto-generation library RDoc.Japan Society of Fluid Mechanics, 06 Aug. 2007, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2007, 246 - 246, Japanese
- 日本惑星科学会, 25 Mar. 2007, 遊・星・人 : 日本惑星科学会誌, 16(1) (1), 3 - 3, Japanese謝辞ならびに会費値上げのお願い
- 2007, 日本惑星科学会秋季講演会予稿集, 2007, 95, Japanese
- 日本気象学会, 2007, 天気, 54(11) (11), 937 - 940, JapaneseGeophysical fluid dynamics (GFD)
- We develop a two-dimensional fluid dynamical model that incorporates condensation of H_2O and NH_3 and the production reaction of NH_4SH. We run the model for a long simulation time in order to examine the structure of moist convection layer in Jupiter's atmosphere that establishes through a large number of life cycles of convective clouds. Our results show that H_2O and NH_4SH cloud particles are advected to the altitudes above the NH_3 condensation level. The convective motion and the distribution of condensible species depend on the deep tropospheric mixing ratios of condensible volatiles.日本流体力学会, 2007, 日本流体力学会年会講演論文集, 2007(2) (2), 101 - 106, Japanese
- 日本気象学会, 2007, 天気, 54, 119-122(2) (2), 119 - 122, Japanese惑星気象学の近年の展開[Refereed]
- 2007, エアロゾル研究(日本エアロゾル学会学会誌), 22, 101-106, Japanese木星大気の雲対流 (Moist Convection in Jupiter's Atmosphere)[Refereed]
- 日本気象学会, 2007, 天気, 54, 185-190, 238 - 238, JapaneseRDoc を用いた数値モデルのドキュメント生成
- 2007, CGER's supercomputer activity report", 14-2005, 69-76, English"Equatorial precipitation patterns in aqua-planet experiments: effects of vertical turbulent mixing processes"
- 08 Aug. 2006, エアロゾル科学・技術研究討論会, 23rd, 219 - 220, Japanese木星大気における雲対流
- Report on the AGU Chapman Conference on Jets and Annular Structures in Geophysical FluidsAGUは毎年何件かの特定のテーマについて50～100人規模のチャップマン会議を各地で開催している.今回,Robinson(Univ. Illinois)と余田(京都大学)がコンビーナーとなり,2006年1月9～12日,ジョージア州サバンナで「地球流体中のジェットと環状構造」に関するチャップマン会議を,KAGI21,NSFとの共催で開催した(第1図に会議のポスター[figure]).Allison(NASA/GISS),Baldwin(NWRA),林(北海道大学),Haynes(Univ. Cambridge),Huang(LDEO),Rhines(Univ. Washington),Thompson(Colorado State Univ.),Vallis(Princeton Univ.)の8氏をプログラム委員に招いて,2年以上をかけて準備してきた会議である.日米をはじめ13か国から70余名の参加者があり,(A)大気中のジェット,(B)海洋中のジェット,(C)大気の環状変動,(D)惑星大気のジェットと環状流,(E)地球流体力学的にみたジェット,の5つの広範だが関連深い話題について,レビュー講演(6件),招待講演(22件),および,ポスター発表(40余件)を行った.レビュー講演は,各分野で主導的な役割を果たしてきたMcIntyre(Univ. Cambridge),Lee(Pennsylvania State Univ.),Marshall(MIT),Wallace(Univ. Washington),Allison,Rhinesの6氏にお願いした.この会議のハイライトの1つは,太平洋域の高分解能数値シミュレーション(Nakano and Hasumi,2005)で予言的に見出され,観測データで発見された海洋中の多重東西ジェット構造である.木星型惑星に見られる多重の環状流との類似性や,回転球面上の2次元乱流中におけるジェット形成メカニズムとの関連など,幅広い分野の研究者を巻き込んで熱い議論がなされた.また,傾圧擾乱による対流圏界面亜熱帯ジェットの維持過程が南極周極流のそれと力学的に相似な現象と認識しうる(基本場の傾圧性が南北加熱差によって維持されるか,海面での摩擦応力によって維持されるか,の違いはあるが)という話題も,地球流体力学的普遍性を具体的に示す好例であった.さらに,周極ジェット気流の時間変動が特徴的に環状パターンを示すという認識が,環状"mode"であるかどうかは措いても,天候の延長予報や今世紀中の気候変化予測などにも役立ちうる可能性が指摘され,実用的応用的な興味も喚起した.この機会に,KAGI21で開発した地球流体力学計算機実験集(Yoden et al., 2005)のCDを参加者全員に配布した.これは,地球流体力学の基本的な数値実験演習問題をパソコンでインタラクティブに実行し,計算結果のアニメーションを見ることができるソフトウェアである.会議終了後すでにいくつかの好意的な反応を得ており,希望者には無償で配布中である.サバンナは米国南部の観光小都市であり,会場となったホテルの近くにも昼食・夕食をみんなで食べられるレストランが多くあった.気のあった仲間同士で出かけてゆっくりと科学的な議論を続けたり,また,それぞれの近況情報を交わしたりできた.最終日のパーティーでは,McIntyre氏が飛び入りでPV song(ビートルズの"Let It Be"の替え歌)を歌い,皆の喝采を浴びた.英国あたりでは, IPVといっていた頃から歌われてきた替え歌のようである.今回の会議後,林氏が火付け役,McIntyre氏が先導役(掻き混ぜ係?)となって歌詞に関するメールのやり取りが続いた.原作のHall(CNRS),Thuburn(Univ. Exeter),さらにはHoskins(Univ. Reading),Wallace,Palmer(ECMWF),Emanuel(MIT)氏らビッグネームも加わって盛り上がり,その統一版が完成した.第2図[figure]に歌詞を掲載するので,PVファンは味わっていただきたい.http://www.lthe.hmg.inpg.fr/~hall/pvsong/pvsong.shtmlには,Hall氏の演奏もある.次節以降は,プログラム委員の林氏,および,参加者有志(アイウエオ順)の報告である.日本気象学会, 30 May 2006, Tenki, 53(5) (5), 405 - 412, Japanese
- 京都大学, Apr. 2006, 数理解析研究所講究録, 1483, 62 - 71, Japanese高速に回転する球面上の2次元順圧減衰性乱流(非線形波動の数理と応用)
- AM05-13-013 Design and implementation tests of a dynamical core for a general circulation model with a flexible and readable source codeAiming for an atmospheric general circulation model (GCM) with readability and flexibility, a dynamical core is newly designed and implemented. Readability and flexibility are expected to be increased by the use of advantageous features of Fortran 90 and by proposing a programming style. The programming style is to help us imagine the corresponding equations of the original physical system. The implemented dynamical core is examined by the benchmark test for GCM dynamical core proposed by Held and Suarez (1994). According to the results of 1200 day integration with the horizontal resolutions of T21, T42, and T63, it is confirmed that the Hadley circulation and mid-latitudinal disturbances are well expressed.Japan Society of Fluid Mechanics, 05 Sep. 2005, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2005, 268 - 268, Japanese
- The structure of convective clouds in Titan's troposphere and their role in methane cycle between the atmosphere and the ground surface are investigated using a fluid dynamical model containing parameterized microphysical processes. Cloud convection is driven by a body cooling in the troposphere and heat and methane fluxes from the ground surface. Preliminary result shows the followings: (i) Titan's ground surface must be considerably dry in order to explain the observed methane undersaturation in the lower atmosphere, (ii) even with such dry surface conditiion, cloud convection is active, (iii) most of the methane rain produced in the convective clouds evaporates in unsaturated lower troposphere.THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, 2005, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2005(0) (0), 96 - 96
- AM05-13-022 Two-dimensional Barotoropic Decaying Turbulence on a Rapidly Rotating SphereA series of numerical experiments on two-dimensional decaying turbulence is performed for a non-divergent fluid on a rotating sphere, with an attention focused into scaling properties of spontaneous circumpolar flow. At a large rotation rate Ω, strong circumpolar westward flow emerges clearly in high lattitudes, and its width is proportional to Ω^<-1/6>, while its strength is roughly to Ω^<1/4>. This scaling properties are not observed for smaller rotation rate employed in previous studies.日本流体力学会, 2005, 日本流体力学会年会講演論文集, 2005, 277 - 277, Japanese
- AM05-13-012 A Resolution Dependence of Equatorial Precipitation Activities Represented in a General Circulation ModelAqua planet experiments are performed in order to investigate horizontal and vertical resolution dependencies of equatorial precipitation activities. The numerical model utilized is AGCM for Earth Simulator (AFES). The cumulus convective scheme is not used. With the increase of vertical resolution from 24 to 96 levels, there are not major differences in precipitation pattern. With the increase of horizontal resolution from T39 to T319, the eastward propagating envelope structures of the westward propagating individual grid-scale disturbances become evident.日本流体力学会, 2005, 日本流体力学会年会講演論文集, 2005, 267 - 267, Japanese
- The Japanese Society for Planetary Sciences, 25 Sep. 2004, Planetary people, 13(3) (3), 145 - 155, JapaneseSimulations of the Martian climate by the use of general circulation models : their current status and the problems of manipulating dust
- D334 Analysis on generation and maintenance mechanisms of the magnetic field in the numerical dynamo benchmarkWe will present some results of analyses about the generation and maintenance mechanisms of the magnetic fields under the condition of the numerical dynamo benchmark easel defined by Christensen et al., (2001). Our analyses suggest that the generation mechanisms of both poloidal and toroidal magnetic fields are macroscopic α effect and that ω effect does not contribute to generation of toroidal magnetic field. Therefore the solution of benchmark easel is classified into α^2-type dynamo.日本流体力学会, Sep. 2004, ながれ(日本流体力学会学会誌), 2004, 608 - 609, Japanese
- A313 A Resolution Dependency of Equatorial Precipitation Activities Represented in a General Circulation ModelAqua planet experiments are performed in order to investigate horizontal and vertical resolution dependencies of equatorial precipitation activities. The numerical model utilized is AGCM for Earth Simulator (AFES). With the increased vertical resolution from 24 to 96 levels, weak precipitation intensity tends to be widely distributed, and the westward propagating grid-scale disturbances become obscured. With the increased horizontal resolution from T39 to T319, the eastward propagating envelope structures of the westward propagating individual grid-scale disturbances become evident.Japan Society of Fluid Mechanics, 09 Aug. 2004, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2004, 490 - 491, Japanese
- Construction of a numerical model for MHD dynamo in rotating sphericall shell as a member of SPMODEL libraryA numerical simulation model of MHD dynamo in a rotating spherical shell is developed as a software tool which enables us to build in or remove physical and/or dynamical processes with ease. It is constructed as one of the resources of the SPMODEL library whose readability and convertibility are enhanced by the use of Fortran 90 programming language. The performance of the present model is verified by conducting some of the standard dynamo benchmark tests.日本流体力学会, Sep. 2003, ながれ(日本流体力学会学会誌), 2003, 124 - 125, Japanese
- Tropical Precipitation Patterns in Response to a Local Warm SST Area : an Ensemble Aqua Planet StudyThe initial development of the atmospheric response to a warm SST anomaly placed at the equator is examined by way of an ensemble switch-on experiment with an aqua planet GCM. An ensemble average of the size of 128 satisfactory reduces the transient noise and reveal the character of the response which follows. In a few days after the switch-on of the SST anomaly, a convection center develops, and a global increase of surface pressure occurs as a barotropic response to the heating. The response afterward is consistent with Gill (1980); a warm Kelvin/Rossby wave-like anomaly is emitted to the east/west of the convection center, except that the characteristic wave speed is that of moist gravity waves. After several days, precipitation is intensified/suppressed to the east/west of the SST anomaly because of the surface frictional convergence/divergence caused by relative low/high pressure anomaly along the equator in the Kelvin/Rossby wave-like response.Japan Society of Fluid Mechanics, 28 Jul. 2003, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2003, 154 - 155, Japanese
- Dependency of equilibrium states of gray atmosphere on solar constant : from the runaway greenhouse to the snowball statesMultiple equilibrium solutions of gray atmosphere are investigated for various values of solar constant. Models used are a three-dimensional primitive model (GCM) and a one-dimensional energy balance model (EBM). Solutions obtained by models are only ice-covered states for small values of solar constant, and only runaway greenhouse states for large values of solar constant. For intermediate values, multiple solutions are obtained, for instance, a combination of ice-covered state, partially ice-covered state and the runaway greenhouse state. The large ice cap instability discussed in previous EBMs also occurs in GCM, since a partially ice-covered state with ice line latitude lower than 20 degree is not obtained. Contrary to results of EBMs, an equilibrium solution in which ice line latitude is 22 degree is obtained in GCM. The solution is maintained by condensation heating near ice line latitude.Japan Society of Fluid Mechanics, 28 Jul. 2003, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2003, 156 - 157, Japanese
- Development of a general circulation model for the Earth type planetary atmosphere AGCM6GFD Dennou CLub AGCM6 is now being designed as an atmospheric general circulation model that helps us to understand dynamics and to perform a comparative study of the planetary atmospheres. The major target is to develop a software structure which enables us to change the model geometry and to build in or remove physical and/or dynamical processes with ease. For the purpose of considering AGCM6 architecture, we are now reinforcing the SPMODEL library. The SPMODEL library is designed to be a series of spectral models of typical equation systems which appear in the field of geophysical fluid dynamics. The spherical shallow water model of SPMODEL library is now provided and can be utilized for further designing of the dynamical core of AGCM6Japan Society of Fluid Mechanics, 28 Jul. 2003, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2003, 158 - 159, Japanese
- 日本気象学会, 2003, 天気, 50(11) (11), 845 - 849, Japaneseシンポジウム「21世紀の大学・研究所の将来像」の報告(その1)
- 02 Oct. 2002, 日本惑星科学会秋季講演会予稿集, 2002, 80, Japanese
- Simple numerical GFD experiments by use of spectral models constructed with ISPACK and gtool4A set of spectral models suitable for performing standard numerical experiments of geophysical and planetary fluid dynamics problems is developed. Our policy for the development of the program codes is, 1) anyone can read, use and modify the source programs; 2) the sources programs should be so understandable that anyone can re-build and modify the programs; 3) visualization and post-processing should be performed easily. For the first and second requirements, Fortran90 modules for spectral models are prepared by wrapping the subroutines of ISPACK Fortran77 library. The programs can be clearly understandable, since they can be written in a similar form to the mathematical expressions with the help of a systematic function naming and array handling features of Fortran90. The self descriptive data format 'gtool4' is used for output to satisfy the third requirement. Commands for simple post-processing of gtool4 data, such as visualizing and arithmetic operations, are also developed.Japan Society of Fluid Mechanics, 23 Jul. 2002, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2002, 68 - 69, Japanese
- 日本気象学会, 2002, 天気, 49(1) (1), 7 - 12, Japanese惑星科学としての力学・気候学(日本気象学会2001年度春季大会シンポジウム「21世紀の気象学-将来展望-」の報告)
- A numerical simulation of internal gravity wave generated by thermal convection in the Martian atmosphereA numerical simulation is performed by using a two-dimensional anelastic model for clear sky condition to investigate the possible characteristics of internal gravity waves generated by thermal convection in the Martian atmosphere. The results show that the vertical and horizontal wave length of simulated internal gravity wave are 10km and 10∿ 15km, respectively. The resultant time series show that the vertical phase velocity are about 10m/sec. According to the dispersion relationship of internal gravity wave, the vertical group velocity become about several m/sec. The horizontal mean value of "effective vertical diffusion coefficient", which is the vertical diffusion coefficient when the vertical diffusion is only responsible for the heat flux, has the same order of magnitude of that used by the 1D photochemical model. The result suggests that the internal gravity wave generated by thermal convection in the Martian lower atmosphere contributes to the vertical mixing in the Martian middle atmosphere.日本流体力学会, 2002, 日本流体力学会年会講演論文集, 2002, 84 - 85, Japanese
- THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, 2002, Abstracts for fall meeting of the Japanese Society for Planetary Science, 2002(0) (0), 58 - 58
- 25 Sep. 2001, 遊・星・人 : 日本惑星科学会誌, 10(3) (3), 112 - 113, Japanese付:惑星科学会運営支援の電子化へむけて(ニュースレター掲載記事の再掲)
- The Japanese Society for Planetary Sciences, Sep. 2001, Planetary people, 10(3) (3), 111 - 113, JapaneseAnnouncement from JSPS
- A two-dimensional numerical simulation of Martian atmospheric convection : dust injection due to convective windA numerical simulation of possible Martian atmospheric convection driven by diurnally-varying radiative heating is performed with a two-dimensional anelastic model employing radiative process appropriate for clear sky conditions. The simulated convection has kilometer-size circulation cell which extends about 5 km horizontally and 10 km vertically. The values of calculated surface stress produced by the kilometer-size convection frequently exceed the minimum threshold value for raising dust from the surface. This result implies that kilometer-size convection forced by diurnally-varying radiative heating may strongly contribute to the dust injection into the Martian atmosphere.Japan Society of Fluid Mechanics, 31 Jul. 2001, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2001, 513 - 514, Japanese
- 日本惑星科学会, 25 Jun. 2001, 遊・星・人 : 日本惑星科学会誌, 10(2) (2), 47 - 47, Japaneseグローバリゼーション
- The Japan Society for Industrial and Applied Mathematics, 2001, Bulletin of the Japan Society for Industrial and Applied Mathematics, 11(1) (1), 50 - 54, Japanese
- Development of gtool4 : a self-descriptive storage format for multi-dimensional numerical dataStorage format for multi-dimensional numerical data is developed for the purpose of researches mainly on geophysical fluid phenomena. In order to achieve platform-independency, netCDF is used for low-level file format. NetCDF conventions for variables and attributes are presented to realize self-descriptiveness, which flexibly support visualization information and various kind of grid-structure. A visualization and analysis software written in Fortran 90 is now under development in order to demonstrate self-descriptiveness of the data formatJapan Society of Fluid Mechanics, 25 Jul. 2000, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2000, 361 - 362, Japanese
- A two-dimensional numerical simulation of Martian atmospheric convection : comparison with a one-dimensional model with parameterized convectionNumerical simulation of Martian atmospheric convection under dust-free condition is performed by use of a 2-dimensional (2D) anelastic atmospheric model. The result of 2D simulation is compered with that of a 1-dimensional (1D) model where the convection is parameterized as vertical diffusion. Treatment of physical processes other than the convection are same in the two models. The 2D model simulation with diurnal change of surface temperature shows that vertical wind velocity reaches 30m/sec and horizontal wind velocity exceeds 20m/sec. The vertical wind velocity is by an order of magnitude larger than that in the 1D model diagnosed from the simulated vertical diffusion coefficient. These results suggest that dust injection to Martian atmosphere can be accomplished by the convective wind superposed on large scale wind.Japan Society of Fluid Mechanics, 25 Jul. 2000, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2000, 399 - 400, Japanese
- The ice ball condition for the planet with gray atmoshpereThe condition of global frozen state (ice ball state) for the planet covered with gray atmosphere is considered by performing the numerical parameter studies with atmospheric general circulation model. When ice albed is 0.2,global frozen states emerge under the condition that the value of solar constant is less than 1100 W/m^2Japan Society of Fluid Mechanics, 25 Jul. 2000, Proceedings, ... meeting of Japan Society of Fluid Mechanics, 2000, 409 - 410, Japanese
- The Japanese Society for Planetary Sciences, 25 Sep. 1999, Planetary people, 8(3) (3), 150 - 159, JapaneseLet us think about the future of Planetary Science of Japan:Ask what you can do for JSPS
- 京都大学, Jan. 1999, 数理解析研究所講究録, 1075, 73 - 84, Japanese回転球面上の2次元乱流における周極渦の形成 (回転流の数理)
- 日本評論社, Sep. 1997, 数学セミナ-, 36(9) (9), 28 - 33, Japanese大気循環と渦 (特集 自然を記述してみると)
- 日本気象学会, 1995, 天気, 42(8) (8), 545 - 558, JapaneseGFD-DENNOU Club. With a historical review and related issues of the education and research environments of Japanese universities
- The Japanese Society for Planetary Sciences, 01 Dec. 1994, Planetary People, 3(4) (4), 276 - 291, JapaneseDynamic Structure of Jovian Atmosphere and Impact of Comets (
Impact of Comet Shoemaker-Levy 9 on Jupiter) - 28 Jun. 1994, ながれ : 日本流体力学会誌, 13(3) (3), 252 - 252, JapaneseMoist convection
- 社団法人日本気象学会, 31 May 1993, 天気, 40(5) (5), 357 - 357, Japanese月例会「長期予報と大気大循環」の報告 : 熱的境界条件が2次元対流セルサイズに及ぼす影響
- 日本気象学会, Nov. 1992, 気象研究ノ-ト, (176) (176), p15 - 49, Japaneseハドレ-循環の力学 (赤道大気上下結合)
- 統計数理研究所, Dec. 1990, 統計数理 = Proceedings of the Institute of Statistical Mathematics, 38(2) (2), 295 - 297, Japanese浅水における過剰反射とシアー不安定 (統計数理研究所 研究活動 (研究会報告 乱流の統計理論とその応用))
- 日本気象学会, Oct. 1986, 天気, 33(10) (10), p522 - 524, Japanese30〜40日周期振動に関する数値実験 (昭和61年度春季大会シンポジウム「熱帯の大気と海洋」の報告)
- 日本気象学会, Mar. 1983, 天気, 30(3) (3), p133 - 135, Japanese日米セミナ-「中層大気力学」の報告
■ Lectures, oral presentations, etc.
- Workshop on Venus and other related atmospheres, Mar. 2024, English, Kobe, Japan, CPS, Kobe UniversityChemical species in the Venus atmosphere calculated by a GCM with chemistry and cloud microphysicsOral presentation
- Workshop on Venus and other related atmospheres, Mar. 2024, English, CPS, Kobe University, Japan, International conferenceDynamical and thermodynamical structure in cloud layer simulated by a GCM with correlated-k distribution radiative transfer model toward data assimilation with observationOral presentation
- 日本気象学会 2023 年度秋季大会, Oct. 2023, Japanese火星高解像度 LES から得られた流れ場と地表面応力Oral presentation
- 日本気象学会2023年度秋季大会, Oct. 2023, Japanese陸惑星設定を用いた太陽定数増加実験Oral presentation
- 日本気象学会2023年度秋季大会, Oct. 2023, JapaneseAFES-Venusへの精緻な放射モデルの導入：雲層での力学・熱力学的構造Oral presentation
- 日本気象学会2023年度秋季大会, Oct. 2023, JapaneseAFES-Venus低安定度層拡大実験：傾圧不安定の解析Oral presentation
- 日本気象学会2023年度秋季大会, Oct. 2023, Japanese金星大気放射対流平衡の熱力学モデル依存性Oral presentation
- 日本気象学会 2023 年度秋季大会, Oct. 2023, Japanese高速回転する球殻内の非弾性熱対流の長時間積分と木星型惑星大気の表面帯状構造についてOral presentation
- 日本流体力学会 年会2023, Sep. 2023, Japanese高解像度の火星大気 LES から得られた流れ場と地表面応力Oral presentation
- 日本流体力学会 年会2023, Sep. 2023, Japanese高速回転球殻内の非弾性流体の熱対流の長時間積分Oral presentation
- JpGU Meeting 2023, May 2023, Japanese大規模惑星大気数値シミュレーションデータの可視化ツールの開発 -地図投影法の切り替え機能の実現方法の検討-Oral presentation
- JpGU Meeting 2023, May 2023, Japanese金星大気の全球非静力学計算：鉛直対流の影響Poster presentation
- JpGU Meeting 2023, May 2023, JapaneseLong-time integration of anelastic thermal convection in a rapidly rotating spherical shellPoster presentation
- JpGU Meeting 2023, May 2023, JapaneseCharacteristics of the relationship between wind fields and surface stress with high-resolution large eddy simulations for the Martian atmosphereOral presentation
- 日本気象学会2023年度春季大会, May 2023, Japanese静的不安定化の強制を与えた金星大気全球静力学モデルの数値実験Oral presentation
- 金星大気の観測・シミュレーション・データ同化に関する研究会, Mar. 2023, JapaneseAFES-Venus による金星大気構造: 雲層不安定強制を用いた場合Oral presentation
- 金星大気の観測・シミュレーション・データ同化に関する研究会, Mar. 2023, Japanese自転軸の傾きを入れた金星大気循環シミュレーションOral presentation
- 金星大気の観測・シミュレーション・データ同化に関する研究会, Mar. 2023, JapaneseAFESへの精緻な放射スキームの導入に向けてOral presentation
- 2022年度宇宙科学情報解析シンポジウム, Jan. 2023, Japanese大規模惑星大気数値シミュレーションデータの可視化ツールの開発 -共有機能の実装-Oral presentation
- SGEPSS第152回講演会, Nov. 2022, Japanese自転軸の傾きを入れた金星大気循環シミュレーションOral presentation
- 日本気象学会2022年度秋季大会, Oct. 2022, Japanese, 札幌火星大気の全球非静力学高解像度計算Oral presentation
- 令和4年度日本気象学会関西支部第2回例会, Oct. 2022, Japaneseスペクトル法を用いた自転軸対称ハドレー循環の数値実験Oral presentation
- 6th Asia-Pacific Conference on Plasma Physics (AAPPS-DPP), Oct. 2022, English, International conferenceZonal Banded Jets Generated by Thermal Convection in Rapidly Rotating Spherical ShellsInvited oral presentation
- 日本流体力学会 年会2022, Sep. 2022高速回転球殻内の熱対流により引き起こされる表面縞状構造への超粘性の影響Oral presentation
- 日本惑星科学会2022年秋季講演会, Sep. 2022, 水戸火星大気の全球非静力学高解像度計算Poster presentation
- Europlanet Science Congress 2022, Sep. 2022, Palacio de Congresos de Granada, Spain, Spain, International conferenceThermal tides reproduced in the assimilation results of horizontal winds obtained from Akatsuki UVI observations
- JpGU Meeting 2022, Jun. 2022, EnglishSpontaneous gravity wave radiation from thermal tides in the Venus atmospherePoster presentation
- 「富岳で加速する素粒子・原子核・宇宙・惑星」シンポジウム, Jan. 2022, Japanese全球非静力学火星大気計算：地域性・季節性の解析Oral presentation
- 日本気象学会2021年度秋季大会, Dec. 2021, Japanese, 日本気象学会, 三重, Japan, Domestic conference大気吸収係数が海惑星の気候レジーム図に与える影響Oral presentation
- 日本気象学会2021年度秋季大会, Dec. 2021, Japanese, 日本気象学会, 三重, Japan高速回転球殻内の熱対流により生成される高緯度順行ジェット
- 日本気象学会2021年度秋季大会, Dec. 2021, Japanese, 日本気象学会, 三重, Japan金星大気の放射計算と放射対流平衡実験Poster presentation
- 日本気象学会2021年度秋季大会, Dec. 2021, Japanese, 日本気象学会, 三重, Japan金星大気中の自発的な重力波放射の数値実験Poster presentation
- 日本気象学会2021年度秋季大会, Dec. 2021, Japanese, 日本気象学会, 三重, Japan, Domestic conference全球非静力学火星大気大循環モデルの開発：地形あり計算Oral presentation
- 地球電磁気・地球惑星圏学会(SGEPSS) 第150回講演会, Nov. 2021, 地球電磁気・地球惑星圏学会(SGEPSS), オンライン金星探査機「あかつき」の水平風速を用いた客観解析データ作成の試み
- 地球電磁気・地球惑星圏学会(SGEPSS) 第150回講演会, Nov. 2021, Japanese, 地球電磁気・地球惑星圏学会(SGEPSS), on-line全球非静力学金星大気モデルの開発：簡易金星計算Oral presentation
- 日本流体力学会 年会2021, Sep. 2021, 日本流体力学会, オンライン全球非静力学金星大気モデルの開発
- 日本流体力学会 年会2021, Sep. 2021, Japanese, 日本流体力学会, オンライン高速回転球殻内の熱対流により引き起こされる高緯度順行ジ\\ ェットの生成についてOral presentation
- 日本惑星学会2021年秋季講演会, Sep. 2021, Japanese, 日本惑星科学会, オンラインあかつき観測から得られる水平風速を用いた金星客観解析データ作成の試みOral presentation
- 日本惑星学会2021年秋季講演会, Sep. 2021, Japanese, 日本惑星科学会, オンライン全球非静力学火星大気大循環モデルの開発：地形あり計算Oral presentation
- JpGU 2021, Jun. 2021, Japanese, JpGU, Japan回転球殻熱対流により引き起こされる表面縞状構造への超粘性の影響
- JpGU 2021, Jun. 2021, Japanese, JpGU, Japan全球非静力学金星大気モデルの開発：簡易金星計算
- JpGU 2021, Jun. 2021, Japanese, JpGU, オンライン, Japan木星の雲対流構造の数値計算～放射伝達計算による平均冷却鉛直分布を与えた場合～Oral presentation
- JpGU 2021, Jun. 2021, English, JpGU, online, JapanData assimilation of horizontal wind obtained from Akatsuki UVI observations focusing on thermal tides and attempts to produce Venus first analysisPoster presentation
- May 2021, Japanese, 日本気象学会, オンライン木星の雲対流構造の数値計算～放射対流平衡計算の結果を 初期値および基本場として用いるケース～Poster presentation
- 日本天文学会2021年春季年会, Mar. 2021, Japanese火星大気大循環の全球非静力学高解像度シミュレーションに向けてOral presentation
- 日本地球惑星科学連合大会予稿集(Web), 2021Numerical calculation of moist convection in Jupiter’s atmosphere-A case study with an average cooling vertical profile based on a radiative transfer calculation-
- 日本気象学会大会講演予稿集(CD-ROM), 2021木星の雲対流の数値計算~放射伝達計算による平均冷却鉛直分布を与えた場合~
- 日本気象学会大会講演予稿集(CD-ROM), 2020凝結性成分による対流抑制条件を念頭においた木星型惑星の雲対流の数値計算
- 日本地球惑星科学連合大会予稿集(Web), 2020Inhibition of moist convection in the atmospheres of Jovian planets: the case of NH4SH formation by chemical reaction of NH3 and H2S
- 日本地球惑星科学連合大会予稿集(Web), 2020Study on visualization of large numerical simulation data of planetary atmosphere using web map technology
- 日本惑星科学会秋季講演会予稿集(Web), 2020ウェブ地図技術を用いた大規模惑星大気シミュレーションデータ可視化ツールdcwmtの開発
- 第21回非静力学モデルに関するワークショップ, Nov. 2019, 三重大学, Domestic conference非静力学全球大気モデルにおけるQBO的周期振動の時間刻み幅依存性Oral presentation
- 日本気象学会2019年度秋季大会, Oct. 2019, 福岡国際会議場, Domestic conference乾燥大気理想化実験におけるQBO的周期振動のモデル依存性(続報)Oral presentation
- 146th SGEPSS Fall Meeting, Oct. 2019, 熊本市国際交流会館, Domestic conferenceDevelopment of a global non-hydrostatic Martian atmospheric model and its high-resolution simulationOral presentation
- 日本惑星科学会2019年秋季講演会, Oct. 2019, 京都産業大学, Domestic conference非静力学全球火星大気循環モデルの開発と高解像度計算Oral presentation
- 日本流体力学会 年会2019, Sep. 2019, 電気通信大学高解像度金星大気シミュレーションで再現された惑星規模筋状構造Oral presentation
- 日本流体力学会 年会2019, Sep. 2019, 電気通信大学非静力学全球火星大気循環モデルの開発と高解像度計算Oral presentation
- 公開シンポジウム「京」から「富岳」へ：大規模シミュレーションが拓く惑星科学の未来, Sep. 2019, 東京大学 駒場キャンパス火星大気の全球高解像度シミュレーションに向けたモデル開発Oral presentation
- Japan Geoscience Union Meeting 2019, May 2019, Japanese, Makuhari Messe, Chiba, Domestic conferenceConsortium for Planetary Exploration[Invited]Invited oral presentation
- Japan Geoscience Union Meeting 2019, May 2019, Japanese, Makuhari Messe, Chiba, Domestic conferenceRadiative transfer calculation for various planetary atmospheres:Application to a general circulation modelPoster presentation
- 日本気象学会2019年度春季大会, May 2019, Japanese, 国立オリンピック記念青少年総合センタ－, Domestic conference地球流体力学・惑星気象学の推進ならびに関連知見集積のための情報基盤の構築：地球流体電脳倶楽部など[Invited]Invited oral presentation
- 日本気象学会2019年度春季大会, May 2019, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference全球非静力学火星大気大循環モデルの開発と高解像度計算Oral presentation
- Japan Geoscience Union Meeting 2019, May 2019, Japanese, Makuhari Messe, Chiba, Domestic conferenceDevelopment of a global non-hydrostatic Martian atmospheric modeland its high-resolution simulationOral presentation
- Japan Geoscience Union Meeting 2019, May 2019, Japanese, Makuhari Messe, Chiba, Domestic conferenceA study on the dependence of ocean planet climate on solar constant:influence of oceanic heat transport in the case of large absorptioncoefficients of gray atmosphereOral presentation
- Japan Geoscience Union Meeting 2019, May 2019, Japanese, Makuhari Messe, Chiba, Domestic conferenceIs he a bit overkill for English?Oral presentation
- Japan Geoscience Union Meeting 2019, May 2019, English, Makuhari Messe, Chiba, International conferenceZonal mean structure of Venus atmosphere observed in a Venus general circulation model with explicit radiative transferPoster presentation
- International Venus Conference 2019 (The 74th Fujihara Seminar: "Akatsuki" Novel Development of Venus Science), May 2019, English, Hilton Niseko Village, International conferenceZonal mean structure of Venus atmosphere observed in a Venus general circulation model, DCPAM, with explicit radiative transfer calculationPoster presentation
- International Venus Conference 2019 (The 74th Fujihara Seminar: "Akatsuki" Novel Development of Venus Science), May 2019, English, Hilton Niseko Village, International conferencePlanetary-scale streak structure reproduced in high-resolution simulations of the Venus atmosphere with a low-stability layerOral presentation
- Japan Geoscience Union Meeting 2019, May 2019, English, Makuhari Messe, Chiba, International conferenceDevelopment of a Venus' cloud formation scheme for a convection resolving modelPoster presentation
- ポスト「京」萌芽的課題・計算惑星 第3回 公開シンポジウム, Mar. 2019, Japanese, Domestic conference火星大気循環の全球非静力学モデルの開発と高解像度計算Oral presentation
- 日本惑星科学会秋季講演会予稿集(Web), 2019NH4SH生成反応による対流抑制条件を念頭においた木星型惑星の雲対流の数値計算
- 2nd Asia-Pacific Conference on Plasma Physics (AAPPS-DPP), Nov. 2018, English, Kanazawa, International conferenceTurbulence, waves and mean flows.[Invited]Invited oral presentation
- 日本気象学会2018年度秋季大会, Oct. 2018, Japanese, 仙台国際センター, Domestic conference放射伝達を陽に計算した金星大気大循環計算Oral presentation
- 日本気象学会2018年度秋季大会, Oct. 2018, Japanese, 仙台国際センター, Domestic conference高解像度火星大気大循環モデル中の中小規模渦度擾乱Oral presentation
- 日本惑星科学会2018年秋季講演会, Oct. 2018, Japanese, 旭川市科学館サイパル, Domestic conference高解像度火星境界層シミュレーションのデータを用いたダスト巻き上げ過程に関する解析Poster presentation
- Comparative Climatology III, Aug. 2018, English, Lunar and Planetary Institute, Houston, Texas, International conferenceGCM Experiments on Occurrence Condition of the Runaway Greenhouse State: Aquaplanets and Landplanets.Oral presentation
- 42nd COSPAR Scientific Assembly 2018, Jul. 2018, English, International conferenceAkatsuki Reveals Venus Atmosphere Dynamics[Invited]Invited oral presentation
- 日本気象学会2018年度春季大会, May 2018, Japanese, つくば国際会議場, Domestic conference惑星大気放射伝達モデルの構築：金星大気の計算Oral presentation
- 日本地球惑星科学連合2018年大会, May 2018, Japanese, 幕張メッセ, Domestic conference惑星大気の放射伝達計算Poster presentation
- 日本地球惑星科学連合2018年大会, May 2018, Japanese, 幕張メッセ, Domestic conference木星型惑星を想定した雲対流の数値計算～凝結性成分が多いケース～Poster presentation
- 日本気象学会2018年度春季大会, May 2018, Japanese, つくば国際会議場, Domestic conference部分凍結解の初期値依存性を除去した海惑星気候の太陽定数依存性Oral presentation
- 日本地球惑星科学連合2018年大会, May 2018, Japanese, 幕張メッセ, Domestic conference大気大循環モデルを用いた地球気候の太陽定数依存性に関する数値実験Oral presentation
- 日本地球惑星科学連合2018年大会, May 2018, Japanese, 幕張メッセ, Domestic conference海惑星気候の太陽定数依存性に関する数値的研究: 海洋熱容量と海洋熱輸送の効果Oral presentation
- 日本地球惑星科学連合2018年大会, May 2018, Japanese, 幕張メッセ, Domestic conference火星大気循環の全球・高解像度・非静力学計算に向けたモデル開発Poster presentation
- 日本地球惑星科学連合2018年大会, May 2018, Japanese, 幕張メッセ, Domestic conference火星大気高解像度ラージエディシミュレーションによる地表面ダストフラックスの見積もりPoster presentation
- 日本気象学会 2018 年度春季大会, May 2018, Japanese, つくば国際会議場, Domestic conference火星高解像度 LES を用いた地表面タストフラックスの見積もりOral presentation
- Japan Geoscience Union Meeting 2018, May 2018, English, Makuhari Messe, Chiba, International conferenceExamining the superrotation maintenance mechanism in the Venusian atmosphere with AkatsukiOral presentation
- Japan Geoscience Union Meeting 2018, May 2018, English, Makuhari Messe, Chiba, International conferenceDevelopment of a radiative transfer model for planetary atmospheres: Application for Venus atmospherePoster presentation
- Japan Geoscience Union Meeting 2018, May 2018, English, Makuhari Messe, Chiba, International conferenceA Three-dimensional Numerical Simulation of Venus' Cloud-level ConvectionPoster presentation
- ポスト「京」萌芽的課題・計算惑星 第2回 公開シンポジウム, Mar. 2018, Japanese, 神戸大学 統合研究拠点, Domestic conference火星版SCALE-GMの開発：高解像度非静力学火星大気シミュレーションに向けてOral presentation
- Fundamental Aspects of Geophysical Turbulence III, Mar. 2018, English, 名古屋大学, International conferenceNumerical study on small scale vortices in Mars's lower atmosphere[Invited]Invited oral presentation
- Fundamental Aspects of Geophysical Turbulence III, Mar. 2018, English, 名古屋大学, International conferenceDisturbances and energy spectra in a high-resolution global model of the Venus atmosphere[Invited]Invited oral presentation
- 日本気象学会大会講演予稿集, 2018火星高解像度LESを用いた地表面ダストフラックスの見積もり
- 日本地球惑星科学連合大会予稿集(Web), 2018木星型惑星を想定した雲対流の数値計算~凝結性成分が多いケース~
- 日本気象学会2017年度秋季大会, Oct. 2017AFES-Venusによる金星大気のモデリング
- 日本気象学会2017年度秋季大会, Oct. 2017, Japanese, 北海道大学 学術交流会館, Domestic conference惑星大気大循環モデルのための放射伝達モデルの構築Oral presentation
- 地球電磁気・地球惑星圏学会第142 回総会・講演会, Oct. 2017, Japanese, 京都大学 宇治キャンパス, Domestic conference大気大循環モデルを用いた地球気候の太陽定数依存性に関する数値実験Poster presentation
- 地球電磁気・地球惑星圏学会第142 回総会・講演会, Oct. 2017, Japanese, 京都大学 宇治キャンパス, Domestic conference全球海惑星気候の太陽定数依存性の研究：海洋大循環の影響の考察Oral presentation
- 日本気象学会2017年度秋季大会, Oct. 2017, Japanese, 北海道大学 学術交流会館, Domestic conference全球海惑星の気候レジーム〜海洋大循環の効果〜Oral presentation
- 地球電磁気・地球惑星圏学会第142 回総会・講演会, Oct. 2017, Japanese, 京都大学 宇治キャンパス, Domestic conference高速回転する薄い球殻内の熱対流により生成される表層縞帯状構造の消滅Oral presentation
- 日本気象学会 2017 年度秋季大会, Oct. 2017, Japanese, 北海道大学, Domestic conference高速回転する薄い球殻中の対流により引き起こされる 表層の帯状流への計算領域の影響Oral presentation
- 日本気象学会2017年度秋季大会, Oct. 2017, Japanese, 北海道大学 学術交流会館, Domestic conference高解像度金星大気シミュレーションで再現された惑星規模のストリーク構造Oral presentation
- 地球電磁気・地球惑星圏学会第142 回総会・講演会, Oct. 2017, Japanese, 京都大学 宇治キャンパス, Domestic conference高解像度金星大気シミュレーションで再現された惑星規模のストリーク構造Oral presentation
- 日本気象学会2017年度秋季大会, Oct. 2017, Japanese, 北海道大学 学術交流会館, Domestic conference乾燥大気理想化実験におけるQBO的周期振動のモデル依存性Oral presentation
- 日本気象学会 2017 年度秋季大会, Oct. 2017, Japanese, 北海道大学, Domestic conference火星大気境界層高解像度 LES によって得られた地表面応力に関する考察Poster presentation
- Joint SPARC Dynamics & Observations Workshop—QBOi, FISAPS & SATIO-TCS, Oct. 2017, English, International conferenceModel dependence of a QBO-like oscillation in a dry dynamical core experimentOral presentation
- The 49th Annual Division for Planetary Sciences Meeting., Oct. 2017, English, American Astronomical Society, Provo, Utah, U.S.A., International conferenceDisappearance of surface banded structure produced by thermal convection in a rapidly rotating thin spherical shellPoster presentation
- 日本気象学会2017年度秋季大会, Oct. 2017, Japanese, 北海道大学 学術交流会館, Domestic conferenceAFES-Venus による金星大気のモデリング[Invited]Invited oral presentation
- 日本惑星科学会 秋季講演会, Sep. 2017, Japanese, 大阪大学, Domestic conference地球気候の太陽定数依存性: 海陸分布を考慮した大気大循環モデル実験Poster presentation
- 日本惑星科学会2017年度秋季講演会, Sep. 2017, Japanese, 大阪大学 豊中キャンパス, Domestic conference大気海洋海氷結合モデルを用いた全球海惑星気候の太陽定数依存性に関する研究Oral presentation
- 日本惑星科学会 2017 年秋季講演会, Sep. 2017, Japanese, 大阪大学, Domestic conference高速回転する薄い球殻内の熱対流により生成される表層縞帯状構造の消滅Poster presentation
- 日本惑星科学会2017年秋季講演会, Sep. 2017, Japanese, Domestic conference高解像度金星大気シミュレーションで再現された惑星規模のストリーク構造Oral presentation
- 日本惑星科学会 2017 年秋季講演会, Sep. 2017, Japanese, 大阪大学, Domestic conference高解像度の火星大気ラージエディーシミュレーションで得られた地表面応力Oral presentation
- European Planetary Science Congress 2017, Sep. 2017, English, International conferencePlanetary-scale streak structures produced in a high-resolution simulation of Venus atmosphereOral presentation
- JpGU-AGU Joint Meeting 2017, May 2017, English, 幕張メッセ, International conference惑星大気大循環モデルのための放射伝達モデルの開発に向けてOral presentation
- JpGU-AGU Joint Meeting 2017, May 2017, Japanese, 幕張メッセ, International conference惑星大気シミュレーションの高解像度化に向けて：理想化実験におけるQBO的周期振動のモデル依存性Oral presentation
- JpGU-AGU Joint Meeting 2017, May 2017, Japanese, 幕張メッセ, International conference大気海洋海氷結合モデルを用いた水惑星の気候に対する海洋大循環の影響の数値的研究Poster presentation
- JpGU-AGU Joint Meeting 2017, May 2017, English, 幕張メッセ, International conference高解像度金星大気シミュレーションで再現された惑星規模のストリーク構造[Invited]Invited oral presentation
- JpGU-AGU Joint Meeting 2017, May 2017, Japanese, 幕張メッセ, International conference高解像度 LES によって得られた火星大気境界層における循環構造Poster presentation
- JpGU-AGU Joint Meeting 2017, May 2017, Japanese, 幕張メッセ, International conference高温多湿大気における積雲対流の数値実験Oral presentation
- 日本気象学会2017春季大会, May 2017, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference火星大気を想定した高解像度 LES で得られた地表面応力分布Oral presentation
- ポスト「京」萌芽的課題・計算惑星 第1回 公開シンポジウム, Mar. 2017, Japanese, 神戸大学 統合研究拠点, Domestic conference正二十面体格子モデルSCALE-GMによる火星大気シミュレーションに向けてOral presentation
- 国立天文台 惑星科学 セミナー, Feb. 2017, Japanese, 国立天文台 三鷹キャンパス, Domestic conference汎惑星気象・気候モデルは可能かPublic discourse
- WTK Workshop on Aquaplanet - Landplanet, Feb. 2017, English, NAOJ, International conferenceMean zonal flows induced by Boussinesq thermal convection in rotating spherical shells as an application to the gas giant planets.Oral presentation
- WTK Workshop on Aquaplanet - Landplanet, Feb. 2017, English, NAOJ, International conferenceGFD-Dennou Club DCMODEL project.Oral presentation
- WTK Workshop on Aquaplanet - Landplanet, Feb. 2017, English, CPS, Kobe University, International conferenceDevelopment of a coupled model to explore aquaplanet climates and aquaplanet simulation with zonally symmetric dynamic ocean.Oral presentation
- WTK Workshop on Aquaplanet - Landplanet, Feb. 2017, English, NAOJ, International conferenceClimate of synchronously rotating planet.Oral presentation
- 日本気象学会大会講演予稿集, 2017火星大気を想定した高解像度LESで得られた地表面応力分布
- 日本気象学会大会講演予稿集, 2017火星大気境界層高解像度LESによって得られた強い地表面応力の空間分布
- 日本地球惑星科学連合大会予稿集(Web), 2017高解像度LESによって得られた火星大気境界層における循環構造
- Sixth International Workshop on the Mars Atmosphere: Modeling and Observation, Jan. 2017, Granada, Spain., International conferenceHigh resolution simulations of dust devils and global circulation of the Martian atmosphere.Oral presentation
- Sixth International Workshop on the Mars Atmosphere: Modelling and Observations, Jan. 2017, English, International conferenceHigh Resolution Simulations of Dust Devils and Global Circulation of the Martian atmospherePoster presentation
- 第30回大気圏シンポジウム: 講演集録 = Proceedings of the 30th Atmospheric Science Symposium, Dec. 2016, Japanese, 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS), 第30回大気圏シンポジウム（2016年12月5日-6日. 宇宙航空研究開発機構宇宙科学研究所（JAXA)(ISAS)）, 相模原市, 神奈川県 30th Atmospheric Science Symposium (December 5-6, 2016. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan 資料番号: SA6000062018 レポート番号: IV-5雲解像モデルを用いた金星大気重力波の２次元数値実験
- 地球型惑星圏環境に関する研究集会, Dec. 2016, Japanese, 立教大学池袋キャンパス, Domestic conference大循環/気候モデルはどれほど汎惑星的になりうるか[Invited]Invited oral presentation
- 第30回 大気圏シンポジウム, Dec. 2016, Japanese, 宇宙科学研究所, Domestic conference簡易金星版 AFES 高解像度計算における運動エネルギースペクトル解析Oral presentation
- 2016 年日本気象学会秋季大会, Oct. 2016, Japanese, 名古屋大学, Domestic conference簡易金星版 AFES 高解像度計算におけるエネルギースペクトルの鉛直分布Oral presentation
- 2016 年日本気象学会秋季大会, Oct. 2016, Japanese, 名古屋大学, Domestic conferenceSCALE-LES を用いた火星大気高解像度計算で得られた大気最下層の循環構造Poster presentation
- 日本惑星科学会 2016年 秋季講演会, Sep. 2016, Japanese, ノートルダム清心女子大学, Domestic conference高解像度ラージエディーシミュレーションで得られた火星大気最下層における 対流の微細構造Poster presentation
- 熱帯気象研究会, Sep. 2016, English, 京都大学防災研究所, International conferenceReexamination of the concept of "Walker Circulation" --implicationfrom the variety of large-scale tropical atmospheric response to equatorial SST anomaly in Aquaplanet Experiment --.Oral presentation
- AOGS 2016, Aug. 2016, English, China National Convention Centre, Beijing, International conferenceA numerical experiment on occurrence condition of the runaway greenhouse state with an atmospheric general circulation modelOral presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference暴走温室状態の発生条件に関する大気大循環モデル実験Oral presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference汎惑星気象・気候シミュレーションに向けてOral presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference潮汐固定されたガス惑星の大気大循環の多様性 -- 入射中心星放射強度に対する依存性Oral presentation
- 2016 年日本気象学会春季大会, May 2016, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference潮汐固定されたガス惑星の大気大循環の多様性 -- 入射中心星放射強度に対する依存性Oral presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference地球型系外惑星の気候の数値的探索Poster presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference大気海洋海氷結合モデルによる水惑星の気候の数値実験Poster presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference対流が抑制される雲層における凝結物粒子の落下に伴う熱輸送Poster presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference湿潤大気に現れる対流圏界面高度の異なる二つの大気構造Oral presentation
- 2016 年日本気象学会春季大会, May 2016, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference高速回転する薄い球殻内の熱対流により生成される表層縞状構造への 力学的境界条件の影響Oral presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference高速回転する薄い球殻内の熱対流により生成される表層縞状構造への力学的境界条件の影響Poster presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference高解像度LESによる火星ダストデビルの統計的性質Poster presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference金星GCM(AFES)で再現された小規模擾乱の解析Oral presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference火星境界層の高解像度LES実験[Invited]Invited oral presentation
- 日本地球惑星科学連合2016年大会, May 2016, Japanese, 幕張メッセ, Domestic conference雲解像モデルを用いた金星大気重力波の２次元数値実験Oral presentation
- 2016 年日本気象学会春季大会, May 2016, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference雲解像モデルを用いた金星重力波の２次元数値実験Oral presentation
- 日本地球惑星科学連合2016年大会, May 2016, English, 幕張メッセ, Domestic conferenceNumerical simulation of water cycle in a Martian atmosphere by the use of a planetary atmosphere general circulation model, DCPAMPoster presentation
- 2016 年日本気象学会春季大会, May 2016, Japanese, 国立オリンピック記念青少年総合センター, Domestic conferenceLine-by-line 放射計算による湿潤大気の 2 つの圏界面レジームPoster presentation
- 日本気象学会大会講演予稿集, Apr. 2016, JapaneseLine‐by‐line放射計算による湿潤大気の2つの圏界面レジーム
- 2016 年日本天文学会春季大会, Mar. 2016, Japanese, 首都大学東京, Domestic conference暴走温室状態の発生条件に関する大気大循環モデル実験Poster presentation
- 2016 年日本天文学会春季大会, Mar. 2016, Japanese, 首都大学東京, Domestic conference汎惑星気象・気候シミュレーションに向けて[Invited]Invited oral presentation
- 2016年日本天文学会春季大会, Mar. 2016, Japanese, 首都大学東京, Domestic conference高速回転する薄い球殻内の熱対流により引き起こされる表層縞状構造の消滅Poster presentation
- 平成27年度名古屋大学地球水循環研究センター研究集会「リモートセンシング・数値モデリングの利用と高度化による メソ・マイクロスケール大気・海洋現象に関する研究」, Mar. 2016, Japanese, 名古屋大学宇宙地球環境研究所, Domestic conference火星版 CReSS を用いた火星表層環境評価 ,Oral presentation
- International Workshop on "Exoplanets and Disks: Their Formation and Diversity III", Feb. 2016, English, Hotel Nikko Yaeyama, International conferenceTwo humidity regimes of stratosphere on a moist atmosphereOral presentation
- International Workshop on "Exoplanets and Disks: Their Formation and Diversity III", Feb. 2016, English, Hotel Nikko Yaeyama, International conferenceNumerical Modeling of Moist Convection in Saturn's and Uranus' atmospheresOral presentation
- International Workshop on "Exoplanets and Disks: Their Formation and Diversity III", Feb. 2016, English, Hotel Nikko Yaeyama, International conferenceGCM experiments on the occurrence condition of the runaway greenhouse state on Earth-like exoplanetsOral presentation
- International Workshop on "Exoplanets and Disks: Their Formation and Diversity III", Feb. 2016, English, Hotel Nikko Yaeyama, International conferenceDiversity of atmospheric circulations of tidally locked gas giant planets -- dependence on the intrinsic heat flux strength[Invited]Invited oral presentation
- International Workshop on “Exoplanets and Disks: Their Formation and Diversity III, Feb. 2016, English, Hotel Nikko Yaeyama, International conferenceDevelopment of a general circulation model for shallow planetary atmospheres[Invited]Invited oral presentation
- International Workshop on "Exoplanets and Disks: Their Formation and Diversity III", Feb. 2016, English, Hotel Nikko Yaeyama, International conferenceDevelopment of a coupled atmosphere-ocean-seaice modelto explore aquaplanet climatesPoster presentation
- 日本気象学会大会講演予稿集, 2016SCALE-LESを用いた火星大気高解像度計算で得られた大気最下層の循環構造
- 日本惑星科学会秋季講演会予稿集(Web), 2016高解像度ラージエディーシミュレーションで得られた火星大気最下層における対流の微細構造
- Joint Juno-Csssini Jupiter-Saturn Atmospheric Dynamics Meeting, Dec. 2015, English, San Francisco Marriott Marquis, International conferenceExtreme Intermittency of Moist Convection on the Giant Planets[Invited]Invited oral presentation
- 平成25年度「京」を中核とするHPCIシステム利用研究課題 成果報告会, Oct. 2015, Japanese, 日本科学未来館, Domestic conference惑星探査計画に資する, 火星の領域気象実験Poster presentation
- 第138回 SGEPSS総会および講演会, Oct. 2015, Japanese, 東京大学, Domestic conference惑星大気大循環モデル DCPAM を用いた火星大気中の水蒸気分布の計算Oral presentation
- 第138回 SGEPSS総会および講演会, Oct. 2015, Japanese, 東京大学, Domestic conference金星重力波の２次元数値実験Poster presentation
- 日本気象学会 2015 年度秋季大会, Oct. 2015, Japanese, 京都テルサ, Domestic conference金星雲層を想定した鉛直対流の 3 次元数値計算Oral presentation
- 日本気象学会 2015 年度秋季大会, Oct. 2015, Japanese, 京都テルサ, Domestic conference簡易金星版 AFES 高解像度計算における運動エネルギーの波数間収支Oral presentation
- 大会講演予講集, Sep. 2015, Japanese, 日本気象学会C315 簡易金星版AFES高解像度計算における運動エネルギーの波数間収支(「あかつき」金星大気探査カウントダウン,スペシャル・セッション)
- 2015 年日本流体力学会年会, Sep. 2015, Japanese, 東工大大岡山キャンパス, Domestic conference高速回転する薄い球殻内の熱対流により引き起こされる表層縞状構造の消滅Oral presentation
- 日本気象学会 2015 年度春季大会, May 2015, Japanese, つくば国際会議場, Domestic conference惑星大気大循環モデルの構築 － 鉛直一次元設定での数値実験Oral presentation
- JpGU Meeting 2015, May 2015, Japanese, 幕張メッセ, Domestic conference惑星大気大循環モデルの構築 － 鉛直一次元設定での数値実験Oral presentation
- 日本気象学会 2015 年度春季大会, May 2015, Japanese, つくば国際会議場, Domestic conference木星型惑星大気の雲対流の数値実験Oral presentation
- JpGU Meeting 2015, May 2015, Japanese, 幕張メッセ, Domestic conference木星型惑星大気の雲対流の数値実験Oral presentation
- 日本気象学会 2015 年度春季大会, May 2015, Japanese, つくば国際会議場, Domestic conference水蒸気大気の圏界面の推定とハビタブルゾーンの内側境界Poster presentation
- JpGU Meeting 2015, May 2015, Japanese, 幕張メッセ, Domestic conference水蒸気大気の圏界面の推定とハビタブルゾーンの内側境界Oral presentation
- 日本気象学会 2015 年度春季大会, May 2015, Japanese, つくば国際会議場, Domestic conference高速に回転する薄い球殻内の熱対流により引き起こされる表層縞状構造の消滅Oral presentation
- JpGU Meeting 2015, May 2015, Japanese, 幕張メッセ, Domestic conference高速に回転する薄い球殻内の熱対流により引き起こされる表層縞状構造の消滅Oral presentation
- 日本気象学会 2015 年度春季大会, May 2015, Japanese, つくば国際会議場, Domestic conference火星探査のための表層環境評価: 雲解像モデル CReSS の火星大気への適用Poster presentation
- JpGU Meeting 2015, May 2015, Japanese, 幕張メッセ, Domestic conference火星探査のための表層環境評価: 雲解像モデル CReSS の火星大気への適用Oral presentation
- 日本気象学会大会講演予稿集, Apr. 2015, Japanese木星型惑星を想定した雲対流の数値計算
- 日本気象学会大会講演予稿集, Apr. 2015, Japanese, 日本気象学会水蒸気大気の圏界面の推定とハビタブルゾーンの内側境界
- 平成 26 年度系外惑星大研究会, Mar. 2015, Japanese, 東京大学 情報学環 福武ホール, Domestic conference深部対流を考慮した木星型惑星大気循環の多様性 -- 下面熱流分布と大気層厚さの依存性Poster presentation
- 平成 26 年度系外惑星大研究会, Mar. 2015, Japanese, 東京大学 情報学環 福武ホール, Domestic conferenceDevelopment of a radiative transfer model for steam atmospheres and application to Earth-like planetsOral presentation
- 平成２６年度 系外惑星大研究会, Mar. 2015, Japanese, Domestic conferenceDevelopment of a general circulation model for earth-like planetary atmospheresPoster presentation
- 日本地球惑星科学連合大会予稿集(Web), 2015火星探査のための表層環境評価:雲解像モデルCReSSの火星大気への適用
- 日本惑星科学会秋季講演会予稿集(Web), 2015金星雲層を想定した鉛直対流の3次元数値計算
- 大会講演予講集, 2015, Japanese, 日本気象学会P239 惑星大気大循環モデルの構築 : 鉛直一次元設定での数値実験(ポスターセッション)
- 大会講演予講集, 2015, Japanese, 日本気象学会D310 高速回転する薄い球殻内の熱対流により引き起こされる表層縞状構造の消滅(大気力学,一般口頭発表)
- 大会講演予講集, 2015, Japanese, 日本気象学会P238 雲解像モデルCReSSの火星大気への適用 : 地形と大規模循環の効果の導入(ポスターセッション)
- 大会講演予講集, 2015, Japanese, 日本気象学会C316 金星雲層を想定した鉛直対流の3次元数値計算(「あかつき」金星大気探査カウントダウン,スペシャル・セッション)
- 国立環境研究所スーパーコンピュータ利用研究発表会, Dec. 2014, Japanese, 国立環境研究所つくば, Domestic conference系外惑星大気シミュレーションモデルの開発: 火星ダスト循環過程の実装実験Oral presentation
- 東京大学大気海洋研究所共同利用研究集会, Nov. 2014, Japanese, 東京大学大気海洋研究所, Domestic conference赤道降水擾乱のモデル表現の解像度依存性Oral presentation
- 第58回宇宙科学技術連合講演会, Nov. 2014, Japanese, 長崎ブリックホール, Domestic conferenceEstimation of Mars Environment for Mars Surface Exploration SpacecraftOral presentation
- 46th Meeting of the Division for Planetary Sciences, Nov. 2014, English, Arizona, USA, International conferenceNumerical Simulations of Jupiter's Moist Convection Layer: Structure and Dynamics in Statistically Steady StatesOral presentation
- 平成24年度「京」を中核とするHPCIシステム利用研究課題 成果報告会, Oct. 2014, Japanese, Shinagawa, Domestic conference惑星探査計画に資する、惑星大気の高解像度実験Oral presentation
- 日本気象学会 2014 年度秋季大会, Oct. 2014, Japanese, 福岡国際会議場, Domestic conference惑星大気大循環モデル DCPAM を用いた MELOS1 探査機のための 火星表層環境評価Poster presentation
- 日本気象学会 2014 年度秋季大会, Oct. 2014, Japanese, 福岡国際会議場, Domestic conference木星大気の雲対流と大気構造Oral presentation
- 日本気象学会 2014 年度秋季大会, Oct. 2014, Japanese, 福岡国際会議場, Domestic conference非灰色放射および雲スキームを用いた同期回転惑星大気の数値実験Oral presentation
- 日本気象学会 2014 年度秋季大会., Oct. 2014, Japanese, 福岡国際会議場, Domestic conference高速回転する薄い球殻中の対流により引き起こされる表層の帯状流Oral presentation
- 日本気象学会 2014 年度秋季大会, Oct. 2014, Japanese, 福岡国際会議場, Domestic conference系外惑星大気の 3 次元計算のための放射モデル開発Oral presentation
- 日本気象学会 2014 年度秋季大会, Oct. 2014, Japanese, 福岡国際会議場, Domestic conference火星におけるダスト循環過程スキームの DCPAM への実装とそれを用いた地表面ダストフラックスのパラメータ実験Oral presentation
- 日本気象学会大会講演予稿集, Sep. 2014, Japanese, 日本気象学会木星大気の雲対流と大気構造
- 大会講演予講集, Sep. 2014, Japanese, 社団法人日本気象学会B168 系外惑星大気の3次元計算のための放射モデル開発(惑星大気科学の現在,スペシャル・セッション)
- 大会講演予講集, Sep. 2014, Japanese, 社団法人日本気象学会B158 火星ダスト巻き上げスキームのDCPAMへの実装及び地表面ダストフラックス診断実験(惑星大気科学の現在,スペシャル・セッション)
- 大会講演予講集, Sep. 2014, Japanese, 社団法人日本気象学会B160 初期火星大気中の主成分凝結対流の二次元数値実験 : 雲分布の凝結核数混合比に対する依存性(惑星大気科学の現在,スペシャル・セッション)
- 大会講演予講集, Sep. 2014, Japanese, 社団法人日本気象学会B167 同期回転惑星の大気循環における雲の効果に関する数値実験(惑星大気科学の現在,スペシャル・セッション)
- 日本惑星科学会秋期講演会予稿集, Sep. 2014, Japanese, 日本惑星科学会P1-01 木星型惑星を想定した雲対流の数値計算(ポスターセッション1,ポスター発表)
- 日本惑星科学会秋期講演会予稿集, Sep. 2014, Japanese, 日本惑星科学会O1-03 火星ダスト巻き上げスキームの大気大循環モデルDCPAMへの実装及びダスト巻き上げフラックス診断実験(口頭発表セッション1 惑星大気,口頭発表)
- 日本惑星科学会秋期講演会予稿集, Sep. 2014, Japanese, 日本惑星科学会O1-05 同期回転惑星大気の数値実験 : 昼夜間熱輸送に関する検討(口頭発表セッション1 惑星大気,口頭発表)
- 日本惑星科学会秋期講演会予稿集, Sep. 2014, Japanese, 日本惑星科学会O1-06 初期火星大気中の主成分凝結対流の二次元数値実験 : 雲分布の凝結核数混合比に対する依存性(口頭発表セッション1 惑星大気,口頭発表)
- 日本惑星科学会2014年秋季講演会, Sep. 2014, Japanese, 東北大学片平キャンパス, Domestic conference木星型惑星を想定した雲対流の数値計算Poster presentation
- 日本惑星科学会2014年秋季講演会, Sep. 2014, Japanese, 東北大学片平キャンパス, Domestic conference同期回転惑星大気の数値実験： 昼夜間熱輸送に関する検討Oral presentation
- 日本惑星科学会2014年秋季講演会, Sep. 2014, Japanese, Domestic conference大気大循環モデルのための放射モデル開発： 同期回転惑星大気Oral presentation
- 日本惑星科学会2014年秋季講演会, Sep. 2014, Japanese, 東北大学片平キャンパス, Domestic conference初期火星大気中の主成分凝結対流の二次元数値実験 ー 雲分布の凝結核数混合比に対する依存性 ーOral presentation
- 日本流体力学会年会, Sep. 2014, Japanese, 東北大学, Domestic conference高速回転する薄い球殻内の熱対流により引き起こされる表層の帯状流Oral presentation
- 日本惑星科学会2014年秋季講演会, Sep. 2014, Japanese, 東北大学片平キャンパス, Domestic conference火星ダスト巻き上げスキームの大気大循環モデル DCPAMへの実装及びダスト巻き上げフラックス診断実験Oral presentation
- 第47回月・惑星シンポジウム = Proceedings of the 47th ISAS Lunar and Planetary Symposium, Aug. 2014, Japanese, 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS), 第47回月・惑星シンポジウム (2014年8月4日-6日. 宇宙航空研究開発機構宇宙科学研究所(JAXA)(ISAS)), 相模原市, 神奈川県 47th ISAS Lunar and Planetary Symposium (August 4-6, 2014. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA)(ISAS)), Sagamihara, Kanagawa Japan 形態: カラー図版あり 資料番号: SA6000033005数値気象モデルを用いた着陸探査のための火星表層環境評価—Assessment of Mars surface environment for landing exploration mission by using numerical meteorological models
- 第47回 月・惑星シンポジウム, Aug. 2014, Japanese, ISAS 淵野辺, Domestic conference数値気象モデルを用いた着陸探査のための火星表層環境評価Oral presentation
- AOGS 11th Annual Meeting, Jul. 2014, English, ロイトン札幌, International conferenceSmall and Medium Scale Disturbances and Dust Lifting Represented in High Resolution Simulation of Martian AtmospherePoster presentation
- AOGS 2014., Jul. 2014, English, Sapporo, International conferenceNumerical Simulations of Jupiter’s Moist Convection Layer: Structure and Dynamics in Statistically Steady StatesOral presentation
- AOGS 2014., Jul. 2014, English, Sapporo, International conferenceJapanese Activities toward Constructing General Circulation Models of Planetary Atmospheres[Invited]Invited oral presentation
- AOGS 11th Annual Meeting, Jul. 2014, English, ロイトン札幌, International conferenceImplementing Martian Dust Lifting Scheme into DCPAM, and a Diagnosising Experiment of Surface Dust FluxPoster presentation
- AOGS 11th Annual Meeting, Jul. 2014, English, ロイトン札幌, International conferenceHigh-resolution Large-eddy Simulation of the Martian Planetary Boundary LayerPoster presentation
- AOGS 11th Annual Meeting, Jul. 2014, English, ロイトン札幌, International conferenceEnergy Spectra of Atmospheric Motions Simulated by a High-resolution General Circulation Model of VenusOral presentation
- AOGS 11th Annual Meeting, Jul. 2014, English, ロイトン札幌, International conferenceAssessment of Mars Surface Environment for MELOS1 Lander Using Planetary General Circulation Model DCPAMPoster presentation
- AOGS 2014, Jul. 2014, English, International conferenceA 2D Numerical Simulation of Atmospheric Convection with Condensation of Major Component Under Early Mars ConditionOral presentation
- 日本気象学会春季大会, May 2014, Japanese, 横浜情報文化センター, Domestic conference惑星大気大循環モデル dcpam を用いた MELOS ローバのための 火星表層環境評価Oral presentation
- 日本地球惑星科学連合 2014 年大会., May 2014, Japanese, パシフィコ横浜, Domestic conference惑星大気大循環モデル DCPAM を用いた MELOS1 探査機のための 火星表層環境評価Poster presentation
- 日本地球惑星科学連合 2014 年大会, May 2014, Japanese, パシフィコ横浜, Domestic conference高速に回転する薄い球殻内の熱対流により引き起こされる表層の帯状流Oral presentation
- 日本地球惑星科学連合 2014 年大会., May 2014, Japanese, パシフィコ横浜, Domestic conference巨大惑星を想定した雲対流の 2 次元数値計算Poster presentation
- 日本気象学会春季大会, May 2014, Japanese, 横浜情報文化センター, Domestic conference巨大惑星を想定した雲対流の 2 次元数値計算Poster presentation
- 日本気象学会2014年度春季大会, May 2014, Japanese, 横浜, Domestic conference簡易金星版 AFES 高解像度計算のエネルギースペクトルOral presentation
- 日本地球惑星科学連合 2014 年大会, May 2014, Japanese, パシフィコ横浜, Domestic conference簡易金星大気大循環モデル高解像度計算の運動エネルギースペクトルOral presentation
- 日本地球惑星科学連合 2014 年大会., May 2014, Japanese, パシフィコ横浜, Domestic conference火星におけるダスト巻き上げスキームの DCPAM への実装 とそれを用いた地表面ダストフラックス診断実験Poster presentation
- 日本地球惑星科学連合 2014 年大会, May 2014, Japanese, パシフィコ横浜, Domestic conferenceLine-by-line 放射計算による水蒸気大気の放射特性Oral presentation
- 日本気象学会大会講演予稿集, Apr. 2014, Japanese, 日本気象学会巨大惑星を想定した雲対流の2次元数値計算
- 大会講演予講集, Apr. 2014, Japanese, 日本気象学会D451 簡易金星版AFES高解像度計算のエネルギースペクトル(大気力学,一般口頭発表)
- 惑星大気科学研究会, Mar. 2014, Japanese, 岡山いこいの村, Domestic conference大気大循環モデルによる火星大気での水循環の数値計算Oral presentation
- 大会講演予講集, 2014, Japanese, 日本気象学会B165 高速回転する薄い球殻中の対流により引き起こされる表層の帯状流(惑星大気科学の現在,スペシャル・セッション)
- 大会講演予講集, 2014, Japanese, 日本気象学会P345 惑星大気大循環モデルDCPAMを用いたMELOS1探査機のための火星表層環境評価(ポスターセッション)
- 大会講演予講集, 2014, Japanese, 日本気象学会B161 着陸機による探査のための火星表層環境評価(惑星大気科学の現在,スペシャル・セッション)
- Fifth international workshop on the Mars atmosphere: Modelling and observations, Jan. 2014, English, Oxford Univ., U.K., International conferenceDust Lifting represented in a High Resolution Mars Atmosphere General Circulation ModelPoster presentation
- 5th Subaru International Conference: Exoplanets and Disks: Their Formation and Diversity II, Dec. 2013, English, Sheraton Kona Resort & Spa Keauhou Bay, The Big island of Hawaii, International conferenceDiversity of atmospheric circulations of sycronized rotating Jovian type planets.Oral presentation
- 5th Subaru International Conference: Exoplanets and Disks: Their Formation and Diversity II, Dec. 2013, English, Sheraton Kona Resort & Spa Keauhou Bay, The Big island of Hawaii, International conferenceDevelopment of radiative transfer model for exoplanets with steam atmospheresPoster presentation
- 5th Subaru International Conference: Exoplanets and Disks: Their Formation and Diversity II, Dec. 2013, English, Sheraton Kona Resort & Spa Keauhou Bay, The Big island of Hawaii, International conferenceDevelopment of a general circulation model for earth-like planetary atmospheres and its applicationPoster presentation
- 日本惑星科学会秋期講演会予稿集, Nov. 2013, Japanese, 日本惑星科学会O13-01 大気大循環モデルを用いた木星型惑星大気の数値実験(口頭発表セッション13(惑星大気),口頭発表)
- 日本惑星科学会2013年度秋季講演会, Nov. 2013, Japanese, 石垣市民会館, Domestic conference大気大循環モデルを用いた木星型惑星大気の数値実験Oral presentation
- 日本気象学会秋季大会, Nov. 2013, Japanese, 仙台国際センター, Domestic conference大気大循環モデルを用いた木星型惑星大気の数値実験Oral presentation
- 地球電磁気・地球惑星圏学会第134回総会・講演会, Nov. 2013, Japanese, 高知大学, Domestic conference大気大循環モデルを用いた木星型惑星大気の数値実験Poster presentation
- RIMS International Conference on Zonal Flows in Geophysical and Astrophysical Fluids, Nov. 2013, English, 関西セミナーハウス，京都, International conferenceSurface zonal flows induced by thermal Convection in a rapidly rotating thin spherical shellPoster presentation
- RIMS International Conference on Zonal Flows in Geophysical and Astrophysical Flouds, Nov. 2013, English, 京都, Domestic conferenceAtmospheric general circulations of synchronously rotationg water-covered exoplanets: Dependence on planetary rotation ratePoster presentation
- Nagare, Sep. 2013, JapaneseLinear stability of thermal convection of anelastic fluid in a rotating spherical shell[Invited]
- 2013年日本流体力学会年会, Sep. 2013, Japanese, 東京農工大学, Domestic conference回転球殻内の非弾性流体熱対流の線型安定性Oral presentation
- 2013年日本流体力学会年会, Sep. 2013, Japanese, 日本流体力学会, 東京農工大学, Domestic conference回転球殻内の熱対流による角運動量輸送と太陽差分回転についてOral presentation
- Mathematical analysis of magneto-hydrodynamical processes in stars, Sep. 2013, English, Kanasai Seminar House, International conferenceWeak-field dynamo emerging in a rotating spherical shell with stress-free top and no-slip bottom boundariesOral presentation
- Mathematical analysis of magneto-hydrodynamical processes in stars, Sep. 2013, English, Kanasai Seminar House, International conferenceDifferential rotation and angular momentum transport caused by thermal convection in rotating spherical shells.Oral presentation
- 第46回月・惑星シンポジウム, Aug. 2013, Japanese, 宇宙航空研究開発機構 宇宙科学研究所, Domestic conference火星境界層乱流の LES 実験Oral presentation
- 「宇宙生命計算科学連携拠点」ワークショップ, Jun. 2013, Japanese, 筑波大学, Domestic conference地球流体電脳倶楽部 --知見情報とシミュレーションモデル開発の試み--Oral presentation
- JGPU 2013, May 2013, Japanese, Makuhari Messe, Domestic conference木星大気の雲対流の直接数値計算: 雲対流の間欠性に関する考察Oral presentation
- 日本気象学会春季大会, May 2013, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference木星大気の雲対流の直接数値計算: 雲対流の間欠性に関する考察Oral presentation
- 日本気象学会春季大会, May 2013, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference初期火星大気中の主成分凝結対流の二次元数値実験 - 臨界飽和比と凝結核数 密度に対する依存性Oral presentation
- JPGU2013, May 2013, Japanese, Makuhari Messe, Domestic conference恒星・ガス惑星・氷惑星内部を念頭においた非弾性球殻対流モデルOral presentation
- JPGU2013, May 2013, Japanese, Makuhari Messe, Domestic conference火星大気大循環モデルで表現される火星中層大気子午面循環Poster presentation
- JGPU 2013, May 2013, English, JPGU, Makuhari Messe, Domestic conferenceA 2D numerical simulation of atmoepheric convection with condensation of major component under early Mars condition[Invited]Invited oral presentation
- 大会講演予講集, Apr. 2013, Japanese, 社団法人日本気象学会P334 初期火星大気中の主成分凝結対流の二次元数値実験 : 臨界飽和比と凝結核数密度に対する依存性(ポスター・セッション)
- 大会講演予講集, Apr. 2013, Japanese, 社団法人日本気象学会D411 木星大気の雲対流の直接数値計算:雲対流の間欠性に関する考察(大気力学,口頭発表)
- 平成24年度「京」を中核とするHPCIシステム利用研究課題中間報告会, Mar. 2013, Japanese, HPCI, イイノカンファレンスセンター, Domestic conference惑星探査計画に資する惑星大気の高解像度実験Oral presentation
- 系外惑星大気ワークショップ, Mar. 2013, Japanese, 新学術領域研究 A02 系外惑星大気の数値モデリングと形成進化理論, 東京大学 本郷, Domestic conference同期回転惑星の大気循環と熱収支: 自転角速度および太陽定数依存性Oral presentation
- 大気圏シンポジウム, Mar. 2013, Japanese, ISAS, ISAS 相模原, Domestic conference初期火星大気中の 主成分凝結対流の二次元数値実験 ～臨界飽和比と凝結核数密度に関する パラメータ依存性～Oral presentation
- 第 62 回理論応用力学講演会, Mar. 2013, Japanese, 日本学術会議/「機械工学委員会，土木工学・建築学委員会合同IUTAM分科会」, 東京工業大学大岡山キャンパス, 東京都, Domestic conference海洋に覆われた同期回転惑星の大気大循環Oral presentation
- 惑星大気研究会, Mar. 2013, English, 惑星大気研究会, CPS神戸大学, International conferenceSurface zonal flow induced by turbulent convection in rapidly rotating spherical shellsOral presentation
- 44th Lunar and Planetary Science Conference, Mar. 2013, English, Lunar and Planetary Institute, Woodlands, Texas, USA, International conferenceMERIDIONAL CIRCULATION OF MARTIAN MIDDLE ATMOSPHERE SIMULATED BY A MARS GENERAL CIRCULATION MODELPoster presentation
- 44th Lunar and Planetary Science Conference, Mar. 2013, English, Lunar and Planetary Institute, Woodlands, Texas, U.S.A, International conferenceA numerical study on atmospheric general circulations of synchronously rotating aqua-planets: Dependence on planetary rotation rate and Solar ConstantOral presentation
- 平成 24 年度宇宙科学情報解析シンポジウム, Feb. 2013, Japanese, ISAS, ISAS 相模原, Domestic conference地球流体電脳倶楽部 DCMODELプロジェクトと 数値モデルを用いた惑星大気研究についてOral presentation
- 火星探査ワーキンググループ集会, Feb. 2013, Japanese, 火星探査ワーキンググループ, ISAS 相模原, Domestic conference火星探査のための 局地気象シミュレーション実施計画Oral presentation
- 大気圏シンポジウム・講演集(Web), 2013初期火星大気中の主成分凝結対流の二次元数値実験-臨界飽和比と凝結核数密度に関するパラメータ依存性-
- 大会講演予講集, 2013, Japanese, 日本気象学会D101 大気大循環モデルを用いた木星型惑星大気の数値実験(大気力学,口頭発表)
- 大会講演予講集, 2013, Japanese, 日本気象学会D412 惑星科学研究センター(CPS)における知見アーカイブ(大気力学,口頭発表)
- 京都大学数理解析研究所研究集会 1/9(水)--11(金) 「多重物理・多重スケール乱流現象の数理」, Jan. 2013, Japanese, 京都大学数理解析研究所, 京都大学数理解析研究所, Domestic conference惑星大気の対流現象Invited oral presentation
- 「将来のHPCIシステムのあり方調査研究 アプリケーション分野」第4回全体ミーティング, Jan. 2013, Japanese, 理研(将来の HPC のあり方の調査研究), TKP東京駅八重洲カンファレンスセンター, Domestic conference今後のＨＰＣでの宇宙分野・地球惑星科学分野連携課題について -- 計算惑星科学 --Invited oral presentation
- 平成 24 (2012) 年度地球シミュレータ利用報告会, Jan. 2013, Japanese, 地球シミュレータセンター, JAMSTEC 地球シミュレータセンター, Domestic conferenceAFES を用いた 地球型惑星の大気大循環 シミュレーションOral presentation
- 地球流体データ解析・数値計算ワークショップ., Dec. 2012, Japanese, 理研、地球流体電脳倶楽部, 名古屋大学, Domestic conference地球流体電脳倶楽部 dcmodel プロジェクトについてOral presentation
- 国立環境研究所平成24年度スーパーコンピュータ利用研究報告会, Dec. 2012, Japanese, 国立環境研究所地球環境研究センター, つくば 国立環境研究所, Domestic conference系外惑星大気シミュレーションモデルの開発：ダスト過程の実装と 火星大気実験Oral presentation
- AGU Fall Meeting, Dec. 2012, English, America Geophysical Union, Moscone Center, San Francisco, CA, US., International conferenceNumerical Modeling of Cloud Convection in Jupiter's Atmosphere: robustness and a mechanism of the intermittent emergence of vigorous cumulonimbus cloudsPoster presentation
- AGU Fall Meeting, Dec. 2012, English, America Geophysical Union, Moscone Center, San Francisco, CA, US., International conferenceConstruction of Hierarchical Models for the Fluid Dynamics in Earth and Planetary Sciences : DCMODEL projectPoster presentation
- American Geophysical Union 2012 fall meeting, Dec. 2012, English, American Geophysical Union, San Francisco, USA, International conferenceConstruction of Hierarchical Models for Fluid Dynamics in Earth and Planetary Sciences : DCMODEL projectPoster presentation
- 日本惑星科学会秋期講演会予稿集, Oct. 2012, Japanese, 日本惑星科学会O4-04 薄い回転球殼対流により引き起こされる表層の帯状流(口頭発表セッション4(惑星大気,衝突科学I),口頭発表)
- 日本惑星科学会秋期講演会予稿集, Oct. 2012, Japanese, 日本惑星科学会O4-03 火星境界層乱流のLES実験(口頭発表セッション4(惑星大気,衝突科学I),口頭発表)
- 日本気象学会 2012 年度秋季大会, Oct. 2012, Japanese, 日本気象学会, 北海道大学, Domestic conference惑星大気大循環モデルdcpam を用いた金星設定における放射強制変更実験Oral presentation
- 日本惑星科学会秋季講演会, Oct. 2012, Japanese, 日本惑星科学会, CPS神戸大学, International conference薄い回転球殻対流により引き起こされる表層の帯状流Oral presentation
- 日本気象学会 2012 年度秋季大会, Oct. 2012, Japanese, 日本気象学会, 北海道大学, Domestic conference薄い回転球殻対流により引き起こされる表層の帯状流Oral presentation
- 第132回 SGEPSS講演会., Oct. 2012, Japanese, SGEPSS, 札幌, Domestic conference階層的地球流体スペクトルモデル集SPMODEL を用いた惑星磁場ダイナモ計算Oral presentation
- 日本惑星科学会秋季講演会, Oct. 2012, Japanese, 日本惑星科学会, CPS神戸大学, International conference火星境界層乱流 のLES実験Oral presentation
- 日本気象学会 2012 年度秋季大会, Oct. 2012, Japanese, 日本気象学会, 北海道大学, Domestic conference火星境界層乱流 のLES実験Oral presentation
- 日本気象学会 2012 年度秋季大会, Oct. 2012, Japanese, 日本気象学会, 北海道大学, Domestic conferenceAFESを用いた金星大気の 傾圧不安定に関する研究Oral presentation
- 大会講演予講集, Sep. 2012, Japanese, 社団法人日本気象学会C160 惑星大気大循環モデルdcpamを用いた金星設定における放射強制変更実験(スペシャル・セッション「惑星大気科学の課題と将来の探査計画」,口頭発表)
- 大会講演予講集, Sep. 2012, Japanese, 社団法人日本気象学会C163 AFESを用いた金星大気の傾圧不安定に関する研究(スペシャル・セッション「惑星大気科学の課題と将来の探査計画」,口頭発表)
- 大会講演予講集, Sep. 2012, Japanese, 社団法人日本気象学会C156 火星境界層乱流のLES実験(スペシャル・セッション「惑星大気科学の課題と将来の探査計画」,口頭発表)
- 日本流体力学会年会, Sep. 2012, Japanese, 日本流体力学会, 高知大学朝倉キャンパス, Domestic conference薄い回転球殻対流により引き起こされる表層の帯状流Oral presentation
- 日本流体力学会年会, Sep. 2012, Japanese, 日本流体力学会, 高知大学朝倉キャンパス, Domestic conference熱フラックス固定条件下での高速回転する円筒内の熱対流の 線形安定性に対するエクマン摩擦の影響Oral presentation
- JSST 2012 International Conference on Simulation Technology, Sep. 2012, English, 日本シミュレーション学会（JSST）, 神戸, International conferenceToward high resolution simulation for the atmosphere on Venus by AFES (Atmospheric GCM For the Earth Simulator)Oral presentation
- JSST 2012 International Conference on Simulation Technology, Sep. 2012, English, 日本シミュレーション学会（JSST）, 神戸, International conferenceSurface zonal flow induced by turbulent convection in rapidly rotating spherical shellsOral presentation
- JSST 2012 International Conference on Simulation Technology, Sep. 2012, English, 日本シミュレーション学会（JSST）, 神戸, International conferenceConstruction of Hierarchical Models for the Fluid Dynamics in Earth and Planetary Sciences : DCMODEL projectOral presentation
- The 13th Symposium of SEDI, Study of the Earth's Deep Interior, Jul. 2012, English, SEDI（Study of the Earth's Deep Interior）, University of Leeds, UK., International conferenceEffects of latitudinally heterogeneous buoyancy flux conditions at the inner boundary on MHD dynamos in a rotating spherical shellPoster presentation
- The 13th Symposium of SEDI, Study of the Earth's Deep Interior, Jul. 2012, English, SEDI（Study of the Earth's Deep Interior）, University of Leeds, UK., International conferenceDevelopment of an anelastic convection model in rotating spherical shells for stars, gas and icy giant planetsPoster presentation
- 9th International Planetary School, Jun. 2012, English, CPS Kobe University, Suma, Kobe, JAPAN, International conferenceEffects of latitudinally heterogeneous buoyancy flux conditions at the inner boundary on MHD dynamos in a rotating spherical shellPoster presentation
- Comparative Climatology of Terrestrial Planets, Jun. 2012, English, NASA, USRA 他, Boulder Colorado, U.S., International conferenceAtmospheric general circulations of synchronously rotating terrestrial planets: Dependence on planetary rotation rate Comparative Climatology of Terrestrial PlanetsPoster presentation
- 日本地球惑星科学連合 2012 年大会, May 2012, Japanese, 地球惑星科学連合, 幕張, Domestic conference惑星大気大循環モデルの開発 - 地球大気計算と大循環の自転軸依存性 -Poster presentation
- 日本地球惑星科学連合 2012 年大会, May 2012, Japanese, 日本地球惑星科学連合, 幕張, Domestic conference恒星・ガス惑星の深部大気対流モデルの構築Oral presentation
- 日本地球惑星科学連合 2012 年大会, May 2012, Japanese, 日本地球惑星科学連合, 幕張, Domestic conference回転球殻ダイナモに対する緯度方向不均一な内側浮力フラックス境界条件の影響Oral presentation
- 日本気象学会 2012 年度春季大会, May 2012, Japanese, 日本気象学会, 国立オリンピック記念青少年総合センター, Domestic conference火星極冠上空を想定した主成分凝結対流の二次元数値実験Oral presentation
- 日本地球惑星科学連合 2012 年大会, May 2012, English, 日本地球惑星科学連合, 幕張, International conferenceTwo-dimensional simulation of Martian atmospheric convection with the major component condensation over CO2 ice surfaceOral presentation
- 大会講演予講集, Apr. 2012, Japanese, 社団法人日本気象学会B310 火星極冠上空を想定した主成分凝結対流の二次元数値実験(降水システムII,一般口頭発表)
- 第 8 回 太陽系外惑星大研究会, Apr. 2012, Japanese, 太陽系外惑星大研究会, 国立天文台, 熱海, Domestic conferenceNumerical modeling of moist convection in Jupiter’s atmosphereOral presentation
- 第 8 回 太陽系外惑星大研究会, Apr. 2012, Japanese, 太陽系外惑星大研究会, 国立天文台, 熱海, Domestic conferenceDependence of the atmospheric general circulation of synchronously rotating terrestrial planets on planetary rotation rateOral presentation
- The General Assembly 2012 of the European Geosciences Union (EGU), Apr. 2012, English, EGU, Vienna, Austria, International conferenceDependence of the atmospheric general circulation of synchronously rotating terrestrial planets on planetary rotation rateOral presentation
- 平成 23 (2011) 年度地球シミュレータ利用報告会, Feb. 2012, Japanese, JAMSTEC 地球シミュレータセンター, Domestic conferenceAFES を用いた地球型惑星の大気大循環シミュレーションOthers
- 日本気象学会大会講演予稿集, 2012火星境界層乱流のLES実験
- 大会講演予講集, 2012, Japanese, 日本気象学会C168 薄い回転球殻対流により引き起こされる表層の帯状流(スペシャル・セッション「惑星大気科学の課題と将来の探査計画」,口頭発表)
- 第12回 宇宙科学シンポジウム, Jan. 2012, Japanese, 宇宙航空研究開発機構 宇宙科学研究所, Domestic conference大気観測におけるデータ同化システムの重要性と次期火星探査に向けた計画Others
- AGU Fall Meeting 2011, Dec. 2011, English, San Francisco, California, USA., International conferenceWeak-field dynamo emerging in a rotating spherical shell with stress-free top and no-slip bottom boundaries,Others
- AGU Fall Meeting 2011, Dec. 2011, English, San Francisco, California, USA., International conferenceEffects of an outer stably stratified layer on equatorial surface flows induced by thermal convection in a rotating spherical shell,Others
- 日本気象学会 2011 年度秋季大会, Nov. 2011, Japanese, 名古屋大学東山キャンパス, Domestic conference惑星大気計算のための大循環モデルならびに雲解像モデルの構築,Others
- 日本惑星科学会 2011 年秋季講演会, Nov. 2011, Japanese, 相模女子大学翠葉会館, Domestic conference同期回転惑星における熱収支の自転角速度依存性Others
- 日本気象学会 2011 年度秋季大会, Nov. 2011, Japanese, 名古屋大学東山キャンパス, Domestic conference同期回転惑星における熱収支の自転角速度依存性Others
- 日本惑星科学会 2011 年秋季講演会, Nov. 2011, Japanese, 相模女子大学翠葉会館, Domestic conference共通のプログラムスタイルを持つ大気大循環モデルと雲解像モデルの開発,Others
- 地球電磁気・地球惑星圏学会 2010 年度秋季大会, Nov. 2011, Japanese, 沖縄県市町村自治会館, Domestic conferenceハドレー循環の惑星半径依存性: 大気大循環モデルを用いた数値実験Others
- 大会講演予講集, Oct. 2011, Japanese, 社団法人日本気象学会D111 惑星大気計算のための大循環モデルならびに雲解像モデルの構築(大気力学,一般口頭発表)
- 大会講演予講集, Oct. 2011, Japanese, 社団法人日本気象学会D113 同期回転惑星大気における熱収支の自転角速度依存性(大気力学,一般口頭発表)
- 日本惑星科学会秋期講演会予稿集, Oct. 2011, Japanese, 日本惑星科学会S32-06 共通のプログラムスタイルを持つ大気大循環モデルと雲解像モデルの開発(口頭セッション32:惑星環境進化,口頭発表)
- 日本惑星科学会秋期講演会予稿集, Oct. 2011, Japanese, 日本惑星科学会S32-05 同期回転惑星大気における熱収支の自転角速度依存性(口頭セッション32:惑星環境進化,口頭発表)
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Oct. 2011, Japanese, 日本惑星科学会SP2-03P Supporting activities of CPS (Center for Planetary Science) for organizers of schools, training courses, and workshops
- EPSC-DPS Joint Meeting 2011, Oct. 2011, English, Nantes, France, La Cite Internationale des Congres Nantes Metropole, International conferenceTwo-dimensional model simulation of Martian atmospheric convection with condensation of the major component under fixed thermal forcingOthers
- EPSC-DPS Joint Meeting 2011, Oct. 2011, English, Nantes, France, La Cite Internationale des Congres Nantes Metropole, International conferenceThe Atmospheric General Circulation of Synchronously Rotating Planets: Dependence on Planetary Rotation RateOthers
- JIFT workshop.Hierarchical Self-Organization of Turbulence and flows in Plasmas, Oceans and Atmospheres., Oct. 2011, English, Kyoto University, Domestic conferenceHigh resolution general circulation model experiment of the Martian atmosphere: Resolution dependence of disturbances and dust liftingOthers
- 日本流体力学会年会 2011, Sep. 2011, Japanese, 首都大学東京南大沢キャンパス, Domestic conference同期回転惑星における大気大循環に関する数値実験: 太陽定数依存性Others
- 日本流体力学会年会 2011, Sep. 2011, Japanese, 首都大学東京南大沢キャンパス, Domestic conference回転球殻ダイナモに対する緯度方向不均一な内側浮力フラックス境界条件の影響Others
- 第44回月惑星シンポジウム, Aug. 2011, Japanese, 宇宙航空研究開発機構 宇宙科学研究本部., Domestic conference水平一様熱強制の下で生じる火星大気中の主成分凝結対流の二次元数値実験Others
- AOGS meeting 2011, Aug. 2011, English, Taipei, Taiwan, International conferenceThe variabilities of spontaneously generated tropical precipitation patternsfound in APE Results.Others
- 日本気象学会 2011 年度春季大会, May 2011, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference同期回転惑星における暴走限界の自転角速度・日射分布依存性Others
- 日本地球惑星科学連合 2011 年大会, May 2011, Japanese, 幕張メッセ国際会議場, Domestic conference同期回転惑星における太陽定数増大実験Others
- 日本地球惑星科学連合 2011 年大会, May 2011, Japanese, 幕張メッセ国際会議場, Domestic conference大気大循環構造の惑星パラメタ依存性—地球的条件から火星的条件まで—Others
- 日本気象学会 2011 年度春季大会, May 2011, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference主成分凝結を伴う 2 次元大気対流の準平衡状態Others
- 日本地球惑星科学連合 2011 年大会, May 2011, Japanese, 幕張メッセ国際会議場, Domestic conference主成分の凝結を伴う大気対流Others
- 日本気象学会 2011 年度春季大会, May 2011, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference高解像度火星大気大循環モデルで表現される小規模擾乱によるダスト巻き上げ過程への影響Others
- 日本地球惑星科学連合 2011 年大会, May 2011, Japanese, 幕張メッセ国際会議場, Domestic conference回転球殻MHDダイナモの初期磁場依存性Others
- 日本地球惑星科学連合 2011 年大会, May 2011, Japanese, 幕張メッセ国際会議場, Domestic conference火星大気の高解像度大気大循環実験 : 大気擾乱の解像度依存性Others
- 大会講演予講集, Apr. 2011, Japanese, 社団法人日本気象学会D104 主成分凝結を伴う2次元大気対流の準平衡状態(惑星大気,一般口頭発表)
- 大会講演予講集, Apr. 2011, Japanese, 社団法人日本気象学会D106 同期回転惑星における暴走限界の自転角速度・日射分布依存性(惑星大気,一般口頭発表)
- 第 25 回大気圏シンポジウム, Feb. 2011, Japanese, 宇宙航空研究開発機構 宇宙科学研究本部, Domestic conference同期回転惑星における太陽定数増大実験Oral presentation
- Fourth International Workshop on the Mars Atmosphere: Modelling and Observations, Feb. 2011, English, Paris, Domestic conferenceHigh resolution general circulation model experiments of the Martian atmosphere: Resolution dependence of disturbance and surface stressOral presentation
- Fourth International Workshop on the Mars Atmosphere: Modelling and Observations, Feb. 2011, English, Paris, Domestic conferenceDevelopment of an atmospheric general circulation model and sequential experiments from an Earth-like planet to a Mars-like planetPoster presentation
- 大会講演予講集, 2011, Japanese, 日本気象学会D103 高解像度火星大気大循環モデルで表現される小規模擾乱によるダスト巻き上げ過程への影響(惑星大気,一般口頭発表)
- 大会講演予講集, 2011, Japanese, 社団法人日本気象学会D101 MELOS火星着陸機の気象観測測器の検討(惑星大気,一般口頭発表)
- 日本惑星科学会秋期講演会予稿集, Oct. 2010, Japanese, 日本惑星科学会121 同期回転惑星における太陽定数増大実験(オーラルセッション3 内惑星・ハビタブルプラネット)
- 日本惑星科学会 2010 年秋季講演, Oct. 2010, Japanese, 名古屋大学野依記念学術交流館, Domestic conference同期回転惑星における太陽定数増大実験Oral presentation
- 日本気象学会2010年度秋季大会, Oct. 2010, Japanese, 京都テルサ, Domestic conference同期回転惑星における太陽定数増大実験Oral presentation
- 地球電磁気・地球惑星圏学会 第 128 回総会及び講演会, Oct. 2010, Japanese, 沖縄県市町村自治会館, Domestic conferenceハドレー循環の惑星半径依存性: 大気大循環モデルを用いた数値実験Poster presentation
- 大会講演予講集, Sep. 2010, Japanese, 社団法人日本気象学会D311 同期回転惑星における太陽定数増大実験(大気力学,口頭発表)
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Sep. 2010, Japanese, 日本流体力学会, Numerical experiments of MHD dynamo in a rotating spherical shell with stress-free top and no-slip bottom boundaries are performed. The Ekman number, the Prandtl number, and the ratio of inner and outer radii are fixed to 10^<-3>, 1, and 0.35, respectively. The magnetic Prandtl number is varied from 5 to 50, and the modified Rayleigh number is increased from 1.5 to 10 times critical. All the obtained successful solutions are weak field-dynamo, that is, the total magnetic energy is far less than the total kinetic energy. These solutions are characterized by the two-layer spatial structure. T...Weak-field dynamo emerging in a rotating spherical shell with stress-free top and no-slip bottom boundaries
- WPGM (Western Pacific Geophysical Meeting) 2010, Jun. 2010, English, Taipei, International conferenceThe Atmospheric General Circulation of a Synchronously Rotating Planet and its Dependence on Rotation RatePoster presentation
- 日本地球惑星科学連合 2010 年大会, May 2010, Japanese, 幕張メッセ 国際会議場, Domestic conference同期回転惑星の大気大循環とその自転角速度依存性Oral presentation
- 日本気象学会 2010年度春季大会, May 2010, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference同期回転惑星の大気大循環とその自転角速度依存性Oral presentation
- 日本地球惑星科学連合 2010 年大会, May 2010, Japanese, 幕張メッセ 国際会議場, Domestic conference上端応力無し条件下端粘着条件を課した回転球殻中に出現する弱磁場ダイナモOral presentation
- 日本地球惑星科学連合 2010 年大会, May 2010, English, 幕張メッセ 国際会議場, Domestic conferenceEffects of small and medium scale disturbances on the dust lifting on Mars: general circulation model experimentsOral presentation
- 大会講演予講集, Apr. 2010, Japanese, 社団法人日本気象学会D405 同期回転惑星の大気大循環とその自転角速度依存性(大気力学,一般口頭発表)
- 大会講演予講集, Apr. 2010, Japanese, 社団法人日本気象学会P103 主成分凝結を伴う火星大気対流の二次元数値実験(ポスターセッション)
- DIEW (Data Intensive eScience Workshop) 2010, Apr. 2010, English, 筑波大学, Domestic conferenceGfdnavi, web-based data and knowledge server software for geophysical fluid sciences, Part I: Retionales, stand-alon features, and supporting knowledge documentation linked to data.Others
- ながれ 別冊, 2010, Japanese上端応力無し, 下端滑り無し条件を課した回転球殻中に出現する弱磁場ダイナモ
- 第6回太陽系外惑星大研究会, Jan. 2010, Japanese, 国立天文台, Domestic conference系外惑星の気候探索をめざした数値モデルの開発Others
- 国立天文台 CfCA ユーザーズミーティング, Jan. 2010, Japanese, 国立天文台, Domestic conference回転球殻 MHD ダイナモにおける上部力学的境界条件の影響Others
- CPS 6th International School of Planetary Sciences, Jan. 2010, English, シーパル須磨, International conferenceTwo-dimensional numerical experiments of Martian atmospheric convection with condensation of the major componentPoster presentation
- CPS 6th International School of Planetary Sciences, Jan. 2010, English, シーパル須磨, International conferenceNumerical simulations of planetary atmospheres with land and the ocean by using a general circulation modelPoster presentation
- CPS 6th International School of Planetary Sciences, Jan. 2010, English, シーパル須磨, International conferenceNumerical modeling of moist convection in Jupiter's atmospherePoster presentation
- CPS 6th International School of Planetary Sciences, Jan. 2010, English, シーパル須磨, International conferenceNumerical Experiments of Atmospheric General Circulations on a Synchronously Rotating PlanetPoster presentation
- CPS 6th International School of Planetary Sciences, Jan. 2010, English, シーパル須磨, International conferenceDCMODEL: Hierarchical models for geophysical dynamics and planetary atmospheresPoster presentation
- 第23回大気圏シンポジウム, Dec. 2009, Japanese, 宇宙航空研究開発機構 宇宙科学研究本部, Domestic conference「大気主成分の凝結を考慮した二次元雲対流モデルによる火星大気の数値計算」Others
- 2nd OFES International Workshop and ESC-IPRC Joint Workshop on Computationally-Intensive Modeling of the Climate System, Dec. 2009, English, ハワイ、ホノルル, International conferencemedium and High Tesolution Simulations of Martian AtmosphereOral presentation
- 平成 20 (2008) 年度地球シミュレータ利用報告会, Dec. 2009, Japanese, 地球シミュレーターセンター, Domestic conferenceAFES を用いた地球型惑星の大気大循環のシミュレーションOral presentation
- 日本気象学会 2009 年度秋季大会 スペシャルセッション「惑星大気の多様性」, Nov. 2009, Japanese, アクロス福岡, Domestic conference大気大循環モデルを用いた陸と海の有る惑星の大気大循環計算Oral presentation
- 国立環境研究所 平成21年度スーパーコンピュータ利用研究報告会, Nov. 2009, Japanese, 国立環境研究所(つくば), Domestic conference湿潤惑星大気用数値モデル群の開発および基礎的実験Oral presentation
- 日本気象学会 2009 年度秋季大会 スペシャルセッション「惑星大気の多様性」, Nov. 2009, Japanese, アクロス福岡, Domestic conference系外惑星の気候探索をめざした数値モデルの開発Oral presentation
- 大会講演予講集, Oct. 2009, Japanese, 社団法人日本気象学会C308 系外惑星の気候探索をめざした数値モデルの開発(スペシャル・セッション「惑星大気の多様性」)
- 大会講演予講集, Oct. 2009, Japanese, 社団法人日本気象学会C307 大気大循環モデルを用いた陸と海のある惑星の大気大循環計算(スペシャル・セッション「惑星大気の多様性」)
- STEシュミレーション研究会：粒子加速と波動粒子相互作用＆宇宙プラズマ波動研究会, Oct. 2009, Japanese, 戦災復興記念館, Domestic conference大気大循環モデルを用いた惑星大気の数値計算Oral presentation
- 日本惑星科学会秋期講演会予稿集, Sep. 2009, Japanese, 日本惑星科学会309 惑星大気雲対流モデルの開発(オーラルセッション10 惑星気象・惑星大気)
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Sep. 2009, Japanese, Japan Society of Fluid Mechanics, A 2D non-hydrostatic model to simulate atmospheric convection with condensation of major component is developed. We use quasi-compressible equations with taking cloud particles growth by diffusion process into account. Horizontally uniform body heating/cooling is introduced instead of explicite calculation of the atmospheric radiative transfer. As initial temperature profile, we choose profile of Martian polar cap. For the case with critical saturation ratio (S_<cr>) of 1.35 without falling of cloud particle, after 30 day integration, quasi-equilibrium state is realized. In this state, region above 1km height is covered with clouds. In case with S_<cr>=1.0 without falling of cloud particle, no quasi-equilibrium state seem to be realized. In cases of S_<cr>=1.0, and 1.35 with falling of cloud particle, quasi-equilibrium states seem to exist, which will be confirmed with further time integrations. The results for cases without falling of cloud particle suggest that structure of cloud convection is significantly changed according to the value of S_<cr>.A two dimensional numerical experiment of atmospheric convection with condensation of the major component
- 日本惑星科学会 2009 年秋季講演会, Sep. 2009, Japanese, 東京大学, Domestic conference惑星大気雲対流モデルの開発Oral presentation
- SGEPSS2009 年度秋季大会, Sep. 2009, Japanese, 金沢大学 角間キャンパス, Domestic conference惑星大気の数値モデル研究におけるひとつの戦略Oral presentation
- SGEPSS2009 年度秋季大会, Sep. 2009, Japanese, 金沢大学 角間キャンパス, Domestic conference惑星大域における雲対流の数値モデリングOral presentation
- SGEPSS2009 年度秋季大会, Sep. 2009, Japanese, 金沢大学 角間キャンパス, Domestic conference大気大循環モデルを用いた陸と海の有る惑星の大気大循環計算Oral presentation
- 日本流体力学会年会 2009, Sep. 2009, Japanese, 東洋大学白山キャンパス, Domestic conference主成分の凝結を伴う大気対流の二次元数値実験Oral presentation
- 日本流体力学会年会 2009, Sep. 2009, Japanese, 東洋大学白山キャンパス, Domestic conference回転球殻 MHD ダイナモ解に対する上部力学的境界条件の影響Oral presentation
- 第42回月惑星シンポジウム, Aug. 2009, Japanese, 宇宙航空研究開発機構 宇宙科学研究本部, Domestic conference主成分の凝結を伴う大気対流の二次元数値実験Oral presentation
- ハビタブル惑星ミニワークショップ, Aug. 2009, Japanese, 国立天文台, Domestic conferenceハビタブル惑星大気の数値的研究の一つの戦略Invited oral presentation
- IAMAP, Jul. 2009, English, Palais des Congres, Montreal, CANADA, International conferenceThe varieties of Tropical Precipitation Patterns forced by a Localized Sea Surface Temperature Anomaly on the Equator: Some expectations and APE resultsOral presentation
- IAMAP, Jul. 2009, English, Palais des Congres, Montreal, CANADA, International conferenceThe varieties of spontaneously generated tropical precipitation patterns found in APE ResultsOral presentation
- 地球惑星科学連合 2009 年大会, May 2009, Japanese, 幕張メッセ, Domestic conference木星大気の雲対流の直接数値計算と将来探査計画における雷観測Oral presentation
- 地球惑星科学連合 2009 年大会, May 2009, Japanese, 幕張メッセ, Domestic conference大気主成分の凝結を考慮した 二次元湿潤対流の基礎的数値実験Oral presentation
- 日本気象学会 2009 年度春季大会, May 2009, Japanese, つくば国際会議場, Domestic conference大気主成分の凝結を考慮した二次元湿潤対流の基礎的数値実験Oral presentation
- 日本地球惑星科学連合 2009 年大会, May 2009, Japanese, 幕張メッセ, Domestic conference階層的地球流体モデルのためのデータ入出力ライブラリGtoo15の設計と開発Oral presentation
- 日本気象学会 2009 年度春季大会, May 2009, Japanese, つくば国際会議場, Domestic conference階層的数値モデルのためのデータ入出力ライブラリ Gtool5 の設計と開発Oral presentation
- 大会講演予講集, Apr. 2009, Japanese, 社団法人日本気象学会A402 階層的数値モデルのためのデータ入出力ライブラリGtoo15の設計と開発(大気力学・中高緯度大気)
- 大会講演予講集, Apr. 2009, Japanese, 社団法人日本気象学会A405 大気主成分の凝結を考慮した二次元湿潤対流の基礎的数値実験(大気力学・中高緯度大気)
- JIFT Workshop: Hierarchical Self-Organization of Turbulence and flows in Plasmas, Oceans and Atmospheres, Mar. 2009, English, UCSD, International conferenceOrganization of equatorial precipitation activity in an aqua-planet modelInvited oral presentation
- JIFT Workshop: Hierarchical Self-Organization of Turbulence and flows in Plasmas, Oceans and Atmospheres, Mar. 2009, English, UCSD, International conferenceFormation of jets in decaying turbluence on a rotating sphereInvited oral presentation
- 第 24 回大気圏シンポジウム, Feb. 2009, Japanese, 宇宙航空研究開発機構 宇宙科学研究本部, Domestic conference同期回転惑星における大気大循環の数値実験Others
- 第23回大気圏シンポジウム, Feb. 2009, Japanese, 宇宙航空研究開発機構 宇宙科学研究本部, Domestic conference「同期回転惑星大気における循環構造」Others
- 地球電磁気・地球惑星圏学会総会及び講演会予稿集(CD-ROM), 2009惑星大気における雲対流の数値モデリング
- 大気圏シンポジウム・講演集(Web), 2009大気主成分の凝結を考慮した二次元雲対流モデルによる火星大気の数値計算
- 大気圏シンポジウム・講演集(Web), 2009, Japanese同期回転惑星大気における循環構造
- 平成 20 年度第 2 回日本気象学会北海道支部研究発表会, Dec. 2008, Japanese, 札幌管区気象台, Domestic conference「大気主成分の凝結を考慮した 2 次元雲対流モデルによる火星大気の数値計算」Others
- 第２１回理論懇シンポジウム/国立天文台 CfCA ユーザーズミーティング」, Dec. 2008, Japanese, 国立天文台, Domestic conference「凝結成分存在度をパラメタとした木星雲対流の数値シミュレーションOthers
- Workshop on Rotating Stratified Turbulence and Turbulence in the Atmosphere and Oceans, Dec. 2008, English, Isaac Newton Institute for Mathematical Sciences, International conference"Resolution dependence of dust mass flux simulated by Mars general circulation model"Others
- 日本惑星科学会秋期講演会予稿集, Nov. 2008, Japanese, 日本惑星科学会P233 2次元数値モデルで得られた木星雲対流の間欠性に関する考察(ポスターセッション2)
- 日本惑星科学会秋期講演会予稿集, Nov. 2008, Japanese, 日本惑星科学会107 同期回転惑星大気における循環構造(惑星の形成および惑星大気,オーラルセッション1)
- 日本惑星科学会秋期講演会予稿集, Nov. 2008, Japanese, 日本惑星科学会201 火星大気における渦を伴う鉛直対流の三次元数値計算(火星と水星の科学,オーラルセッション5)
- 日本惑星科学会秋期講演会予稿集, Nov. 2008, Japanese, 日本惑星科学会202 大気主成分の凝結を考慮した二次元雲対流モデルによる火星大気の数値計算(火星と水星の科学,オーラルセッション5)
- 日本惑星科学会 2008 年秋季講演会, Nov. 2008, Japanese, 九州大学, Domestic conference「同期回転惑星大気における循環構造」Others
- 日本惑星科学会 2008 年秋季講演会, Nov. 2008, Japanese, 九州大学, Domestic conference「大気主成分の凝結を考慮した二次元雲対流モデルによる火星大気の数値計算」Others
- 日本気象学会 2008 年度秋季大会, Nov. 2008, Japanese, 仙台国際センター, Domestic conference「上層の安定成層下に閉じ込められた高速回転する球殻内の超臨界対流により 引き起こされる赤道逆行流」Others
- 日本気象学会 2008 年度秋季大会, Nov. 2008, Japanese, 仙台国際センター, Domestic conference「可変性と可読性を考慮した大気大循環モデルの開発: ソースコードの簡潔さを重視したモデル設計」,Others
- 日本気象学会 2008 年度秋季大会, Nov. 2008, Japanese, 仙台国際センター, Domestic conference「3 次元非静力学モデルによる火星大気対流の数値計算: 2 次元モデル計算との比較」Others
- 日本惑星科学会 2008 年度秋季講演会, Nov. 2008, Japanese, 九州大学, Domestic conference「3 次元火星大気非静力学モデルの開発と鉛直対流の数値計算」Others
- 日本惑星科学会 2008 年度秋季講演会, Nov. 2008, Japanese, 九州大学, Domestic conference「2 次元数値モデルで得られた木星雲対流の間欠性に関する考察」Others
- Third International Workshop on The Mars Atmosphere: Modeling and Observations, Williamsburg, Nov. 2008, English, International conference"High Resolution Simulations of the General Circulation of the Martian Atmosphere: Small and Medium Scale Disturbances and Dust Lifting Processes"Others
- Third International Workshop on The Mars Atmosphere: Modeling and Observations, Williamsburg, Nov. 2008, English, International conference"Development of a three dimensional non-hydrostatic model for Martian atmosphere and a numerical simulation of thermal convection"Others
- 大会講演予講集, Oct. 2008, Japanese, 社団法人日本気象学会D304 可変性と可読性を考慮した大気大循環モデルの開発 : ソースコードの簡潔さを重視したモデル設計(スペシャル・セッション「惑星大気の新しい観測と理論」)
- 大会講演予講集, Oct. 2008, Japanese, 社団法人日本気象学会D308 3次元非静力学モデルによる火星大気対流の数値計算 : 2次元モデル計算との比較(スペシャル・セッション「惑星大気の新しい観測と理論」)
- 第 124 回 SGEPSS 総会および講演会, Oct. 2008, English, 仙台市戦災復興記念館, Domestic conference"Resolution dependence of dust mass flux simulated by Mars general circulation model: seasonal variation"Others
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Sep. 2008, Japanese, Japan Society of Fluid Mechanics, We develop a three dimensional non-hydrostatic model and perform a numerical simulation of thermal convection in the Martian atmosphere without background wind and dust radiative heating. The numerical model based on the two dimensional quasi-compressible model developed by Sugiyama et al. (2008). The atmospheric radiative transfer is not calculated explicitly, and a horizontally uniform body cooling is introduced below 5km height. After 12 hours of integration, the thermal convection whose horizontal scale of updraft region is several km is developed. The upward wind velocity reaches from 10 to 15m/sec while the downward wind velocity is about several m/sec. At the lowest level of the three dimensional model (z=50m), isolated vertical vortexes which horizontal scale is about several hundred m are developed frequently. This result suggests that the vertical vortex like dust devils may be naturally developed accompanied with the convective motion without background wind.Development of a three dimensional non-hydrostatic model for Martian atmosphere and a numerical simulation of thermal convection
- 日本流体力学会 年会 2008, Sep. 2008, Japanese, 神戸大学, Domestic conference「高解像度火星大気大循環モデルで表現されるダスト巻き上げ過程」Others
- 日本流体力学会年会 2008, Sep. 2008, Japanese, 神戸大学六甲台キャンパス, Domestic conference「回転 MHD ダイナモにおける力学的境界条件の影響」Others
- 日本流体力学会 年会 2008, Sep. 2008, Japanese, 神戸大学, Domestic conference「3 次元火星大気非静力学モデルの開発と鉛直対流の数値計算」Others
- 第 41 回月惑星シンポジウム, Aug. 2008, Japanese, 宇宙航空研究開発機構 宇宙科学研究本部, Domestic conference「3 次元火星大気非静力学モデルの開発と鉛直対流の数値計算」Others
- 日本地球惑星科学連合 2008 年大会, May 2008, Japanese, 幕張メッセ, Domestic conference「木星大気を念頭においた湿潤大気のための大循環モデルの開発および数値実験」Others
- 日本地球惑星科学連合 2008 年大会, May 2008, Japanese, 幕張メッセ, Domestic conference「上層の安定成層下に閉じ込められた高速回転する球殻内の超臨界対流により 引き起こされる赤道逆行流」Others
- 日本地球惑星科学連合 2008 年大会, May 2008, Japanese, 幕張メッセ, Domestic conference「火星大気大循環モデルで表現されるダスト巻き上げ量の解像度依存性」Others
- 日本気象学会 2008 年度春季大会, May 2008, Japanese, 横浜市開港記念会館, Domestic conference「火星大気大循環モデルで表現されるダスト巻き上げ量の解像度依存性」Others
- 日本地球惑星科学連合 2008 年大会, May 2008, Japanese, 幕張メッセ, Domestic conference「下端に粘着条件・上端に応力無し条件を課した回転球殻 MHD ダイナモ計算」Others
- 日本地球惑星科学連合 2008 年大会, May 2008, Japanese, 幕張メッセ, Domestic conference「3 次元火星大気非静力学モデルの開発と鉛直対流の数値計算」Others
- 日本流体力学会年会講演論文集, 2008, Japanese, 日本流体力学会, In order to investigate the effects of small and medium scale atmospheric circulation and disturbances on dust lifting process on Mars, the high resolution simulations of the Martian atmosphere are performed by using a Mars general circulation model. The simulations with horizontal resolutions of 89, 44, and 22km show that the dust lifting amount increases with increasing resolution. The increase of dust lifting amount is mainly caused by the lifting around several regions with characteristic orographic features, such as the Valles Marineris and the Hellas basin. The analysis of dust lifting phenomena in the Valles Marineris region shows that the superposition of local slope wind and the return flow of meridional circulation causes the large dust lifting in the region. This implies that the effects of small and medium scale local orographic circulation play an important role in lifting dust on Mars.Dust lifting process represented by a high resolution Mars general circulation model
- 日本流体力学会年会講演論文集, 2008, Japanese, 日本流体力学会, Numerical experiments of magnetohydrodynamic dynamos driven by thermal convection in a rotating spherical shell with a free-slip top boundary and a no-slip bottom boundary are performed. Non-dimensional numbers for the experiments are the modified Rayleigh number Ra=100, the Ekman number E=10^<-3>, the Prandtl number Pr=1, the ratio of inner and outer radii ξ=0.35. The magnetic Prandtl number Pm is varied from 5 to 50. Time integration of non-magnetic thermal convection is carried out until a quasi-steady state is established, and then MHD dynamo calculation is carried out starting from the quasi-steady state with a dipole and toroidal magnetic field. In the non-magnetic thermal convection case, the obtained solution consists of well-organized spiral vortex columns aligned with the rotation axis. A strong prograde zonal flow is produced at the top of the spherical shell in contrast to the simulations with the both no-slip boundaries. In the MHD dynamo cases, calculated magnetic fields fall into decay at all magnetic Prandtl numbers. The strong prograde zonal flow, which is prominent in the case of non-magnetic thermal convection, does not appear, but a slow retrograde zonal flow is produced at the top of spherical shell. As a result, the omega effect expected from the strong zonal flows does not seem to operate effectively.MHD dynamo in a rotating spherical shell: Influence of mechanical boundary conditions
- 日本流体力学会年会講演論文集, 2008, Japanese, 日本流体力学会, Finite amplitude thermal convection in a rapidly rotating spherical shell associated with a stably stratified layer forced near the outer surface is investigated. Systematic numerical experiments are performed with the Ekman number E=10^3, the Prandtl number P=1 and the inner/outer radius ratio η=0.4, and show that existence of a strongly stratified upper layer enhances generation of equatorial retrograde flows when the Rayleigh number is ten times larger than the critical value. Although the convective flows become turbulent and do not form regular Taylor-column type vortices in the deep region, they still cannot erode the stably stratified layer. The effect of the stratified layer is to introduce a virtual boundary between the stable and convective layers, which is subject to an intermediate dynamical condition between the no-slip and the free-slip and actually increases the inner/outer radius ratio.Retrograde equatorial surface flows generated by thermal convection under a stably stratified layer in a rotaiting spherical shell
- 大気圏シンポジウム, 20083次元非静力学モデルによる火星大気対流の数値計算
- 大会講演予講集, 2008, Japanese, 日本気象学会D202 火星大気大循環モデルで表現されるダスト巻き上げ量の解像度依存性(大気力学II)
- 大会講演予講集, 2008, Japanese, 日本気象学会D310 上層の安定成層下に閉じ込められた高速回転する球殻内の超臨界熱対流により引き起こされる赤道逆行流(スペシャル・セッション「惑星大気の新しい観測と理論」)
- 平成 19 年度スーパーコンピュータ利用研究報告会, Nov. 2007, Japanese, 国立環境研究所, Domestic conference大気大循環モデルに見られる赤道域降水活動の表現の多様性に関する研究Others
- APE Workshop 2007, Nov. 2007, English, Chiba Institute of Science, Japan, International conferenceOn the varieties of spontaneously generated tropical precipitation patterns,Others
- APE Workshop 2007, Nov. 2007, English, Chiba Institute of Science, Japan, International conference"On the varieties of tropical precipitation patterns forced by an SST anomaly on the equator:some expectations and results"Others
- Workshop on Planetary Atmospheres 2007, Nov. 2007, English, Greenbelt, Meryland. US, International conference"Numerical Modeling of Moist Convection in Jupiter's Atmosphere"Others
- 日本気象学会 2007 年度秋季大会, Oct. 2007, Japanese, Domestic conference火星大気子午面循環の季節変化,Others
- 日本気象学会 2007 年度秋季大会, Oct. 2007, Japanese, 北海道大学, Domestic conference可変性と可読性を考慮した大気大循環モデルの開発と湿潤惑星の数値実験」Others
- 日本気象学会 2007 年度秋季大会, Oct. 2007, Japanese, 北海道大学, Domestic conference3 次元非静力学モデルによる火星大気対流の数値計算」Others
- 39th Meeting of the AAS Division for Planetary Sciences, Oct. 2007, English, Orlando, FL, USA, International conference"Numerical Experiment On An Atmospheric Circulation Of A Synchronously Rotating Planet"Others
- 大会講演予講集, Sep. 2007, Japanese, 社団法人日本気象学会B305 可変性と可読性を考慮した大気大循環モデルの開発と湿潤惑星の数値実験(スペシャルセッション「さまざまな対流」)
- 大会講演予講集, Sep. 2007, Japanese, 社団法人日本気象学会B306 同期回転惑星の大気大循環の数値計算(スペシャルセッション「さまざまな対流」)
- ながれ(日本流体力学会学会誌), Sep. 2007, Japanese, 日本流体力学会, For the purpose of investigating possible fluid motion in the Mercury's outer core, the linear stability of convection in a rotating spherical shell is analyzed for various values of shell depth with different mechanical and thermal conditions.Varying the spherical shell depth in rotating thermal convection
- 日本惑星科学会 2007 年度秋季大会, Sep. 2007, Japanese, 高知大学, Domestic conference木星を念頭においた湿潤惑星の大気大循環モデルによる数値実験Others
- 2007 年日本惑星科学会秋季講演会, Sep. 2007, Japanese, Domestic conference火星大気子午面循環の構造Poster presentation
- 第122回 SGEPSS 総会および講演会, Sep. 2007, Japanese, Domestic conference火星大気子午面循環の季節変化Poster presentation
- 日本惑星科学会 2007 年度秋季講演会, Sep. 2007, Japanese, 高知大学, Domestic conference3 次元火星大気非静力学モデルの開発と放射対流の数値計算,Others
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Aug. 2007, Japanese, Japan Society of Fluid Mechanics, Aiming for constructing an atmospheric general circulation model (GCM) with high readability and flexibility, desired program structures have been considered and their implementation tests have been performed. A flexible GCM whose programs can be easily changed is useful for investigating the structures of various planetary atmospheres from the viewpoint of comparative planetary science. In order to consider moist atmospheric circulations such as Earth and Jupiter, we have performed following attempts for facilitating exchanges of physical processes; (1) a design of physical process modules, (2) a development of a library for the production of test programs, (3) an improvement of document auto-generation library RDoc.A numerical experiment of a moist planet with a general circulation model
- 日本流体力学会年会 2007, Aug. 2007, Japanese, 東京大学教養学部5号館, Domestic conference大気大循環モデルによる湿潤惑星の数値実験にむけて -可読性と可変性を考慮した大気大循環モデル開発-」Others
- 第40回月惑星シンポジウム, Jul. 2007, Japanese, 宇宙航空研究開発機構宇宙科学研究本部, Domestic conference木星大気の雲対流の直接数値計算Others
- 5th International Planetary Probe Workshop, Jun. 2007, English, Bordeaux (France), International conferenceNumerical Modeling of Moist Convection in Jupiter’s Atmosphere and Future Jupiter Probe Mission,Others
- 日本地球惑星科学連合 2007 年大会, May 2007, Japanese, 幕張メッセ, Domestic conference木星大気の雲対流の直接数値計算: 凝結成分存在度に対する雲の鉛直分布と流れ場の依存性Others
- 日本地球惑星科学連合 2007 年大会, May 2007, Japanese, 幕張メッセ, Domestic conference木星の雲対流層の直接数値計算: 複数成分の凝結を伴う対流の構造Others
- 日本気象学会2007 年度春季大会, May 2007, Japanese, 代々木国立オリンピック記念青少年総合センター, Domestic conference木星の雲対流層の直接数値計算: 対流運動と雲分布の結成分存在度に対する依存性」Others
- 地球惑星科学連合2007年大会, May 2007, Japanese, 幕張, Domestic conference地球流体データのデータ管理、解析、可視化のためのデスクトップツール兼サーバー 「Gfdnavi」 の概要および将来構想Others
- 日本地球惑星科学連合 2007 年大会, May 2007, Japanese, 幕張メッセ, Domestic conference大気大循環モデルで表現される赤道域降水活動の 放射冷却率鉛直分布依存性Others
- 日本気象学会 2007 年度春季大会, May 2007, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference水惑星実験における赤道域降水パターンに対する 鉛直乱流混合過程の影響,Others
- 日本地球惑星科学連合 2007 年大会, May 2007, Japanese, 幕張メッセ, Domestic conference火星大気大循環モデルで見られた日変化する小規模渦Others
- 日本気象学会 2007 年度春季大会, May 2007, Japanese, 国立オリンピック記念青少年総合センター, Domestic conference火星大気大循環モデルで見られた日変化する小規模渦Others
- 日本地球惑星科学連合 2007 年大会, May 2007, Japanese, 幕張メッセ, Domestic conference可変性と可読性を考慮した大気大循環モデルの設計と実装実験: 物理過程モジュールでの試みOthers
- 大会講演予講集, Apr. 2007, Japanese, 社団法人日本気象学会D465 水惑星実験における赤道域降水パターンに対する鉛直乱流混合過程の影響(熱帯大気)
- 大会講演予講集, Apr. 2007, Japanese, 社団法人日本気象学会P224 地球流体データの公開・共有・解析・可視化のためのツールGfdnaviの開発
- 東京大学海洋研究所共同利用研究集会―地球流体における波動と対流の力学―, Mar. 2007, Japanese, Domestic conference木星大気の雲対流の直接数値計算：複数成分の凝結を伴う対流層の構造Others
- 第 8 回惑星圏研究会, Mar. 2007, Japanese, 東北大学, Domestic conference木星の雲対流層の直接数値計算: 複数成分の凝結を伴う対流の構造」Others
- 北海道大学シミュレーションサロン(HSS), Mar. 2007, Japanese, 北海道大学, Domestic conference木星の雲対流の数値シミュレーションOthers
- 科学研究費補助金「特定領域研究」情報爆発IT基盤 平成19年度 成果報告会, Mar. 2007, Japanese, 東京, Domestic conference地球科学データの高度利用と流通のための基盤開発Others
- 第 8 回惑星圏研究会, Mar. 2007, Japanese, 東北大学, Domestic conference高解像度火星大気大循環シミュレーションで見られた中小規模擾乱Others
- 第 21 回大気圏シンポジウム, Feb. 2007, Japanese, 宇宙航空研究開発機構 宇宙科学研究本部, Domestic conferenceH2O, NH3 の凝結とNH4SH の生成反応を考慮した木星大気の雲対流の数値計算木星Others
- 日本流体力学会年会講演論文集, 2007, Japanese, 日本流体力学会, We develop a two-dimensional fluid dynamical model that incorporates condensation of H_2O and NH_3 and the production reaction of NH_4SH. We run the model for a long simulation time in order to examine the structure of moist convection layer in Jupiter's atmosphere that establishes through a large number of life cycles of convective clouds. Our results show that H_2O and NH_4SH cloud particles are advected to the altitudes above the NH_3 condensation level. The convective motion and the distribution of condensible species depend on the deep tropospheric mixing ratios of condensible volatiles.Numerical Modeling of Moist Convection in Jupiter's Atmosphere
- 日本流体力学会年会講演アブストラクト集, 2007木星大気雲対流の直接数値計算
- Abstracts for fall meeting of the Japanese Society for Planetary Science, 2007, THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, For the purpose of investigating fundamental features of thermal convection in the Martian atmosphere, a three-dimensional non-hydrostatic model for the Martian atmosphere is developed and a numerical simulation is performed. The governing equations of the model are based on the quasi-compressible system. The turbulent mixing coefficient is calculated by using a prognostic equation ofsubgrid scale turbulent energy and the surface flux is estimated by using bulk method. As a preliminary experiment, convection is generated by horizontally uniform heating whose profile is given from a result of a one-dimensional radiative convective equilibrium model. The convective field which can be regarded to be in a statically equilibrium state is examined.Development of a three dimensional non-hydrostatic model for Martian atmosphere and a numerical simulation of thermal convection driven by radiative forcing
- 大会講演予講集, 2007, Japanese, 日本気象学会D204 火星大気大循環モデルで見られた日変化する小規模渦(大気力学)
- 大会講演予講集, 2007, Japanese, 日本気象学会B303 火星大気子午面循環の季節変化(スペシャルセッション「さまざまな対流」)
- 大会講演予講集, 2007, Japanese, 日本気象学会D206 木星大気の雲対流の直接数値計算 : 対流運動と雲分布の凝結成分存在度に対する依存性(大気力学)
- 大会講演予講集, 2007, Japanese, 日本気象学会B302 3次元非静力学モデルによる火星大気対流の数値計算(スペシャルセッション「さまざまな対流」)
- 大会講演予講集, 2007, Japanese, 日本気象学会B304 2次元対流モデルで明らかにされた木星大気の雲対流構造(スペシャルセッション「さまざまな対流」)
- Abstracts for fall meeting of the Japanese Society for Planetary Science, 2007, THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Extrasolar planets near stars is considered to rotatesynchronously due to strong tidal force. On a synchronously rotating planet, one side is permanentlyilluminated while the other side is in perpetual darkness. Joshi et al. (1997) performs an atmospheric GCM simulation on a synchronouslyrotating planet, but their model does not contain hydrologic processes. In this study, a GCM experiment is performed fora moist atmosphere on a synchronously rotating planet, and atmospheric circulation and heat transport are examined. The results indicate thatlongitudinal heat transport in the low latitudinal region is caused by propagation of equatorial Kelvin and Rossby waves,and that in the higher latitudinal regionis caused by baroclinic eddies.A GCM experiment on an atmosphere of a synchronously rotating planet.
- 宇宙航空研究開発機構 宇宙科学研究本部, 第 21 回大気圏シンポジウム講演集, 2007, Japanese"H2O, NH3 の凝結と NH4SH の生成反応を考慮した木星大気の雲対流の直接数値計算"
- 地球シミュレータ 平成 18 年度利用報告会, Jan. 2007, Japanese, Domestic conferenceAFES を用いた地球型惑星の大気大循環シミュレーションOthers
- 大会講演予講集, Sep. 2006, Japanese, 社団法人日本気象学会P356 大気大循環モデルの赤道域対流圏に表れた2種類のケルビン波的シグナル
- エアロゾル科学・技術研究討論会, Aug. 2006, Japanese木星大気における雲対流
- 大会講演予講集, Apr. 2006, Japanese, 社団法人日本気象学会C410 大気大循環モデルで表現される赤道域降水活動の循環構造解析 : 背景風移流と赤道波に着目して(熱帯大気)
- 数理解析研究所講究録, Apr. 2006, Japanese, 京都大学高速に回転する球面上の2次元順圧減衰性乱流(非線形波動の数理と応用)
- 大気圏シンポジウム, 2006火星大気湿潤対流の数値計算
- 大会講演予講集, 2006, Japanese, 日本気象学会A362 火星大気大循環モデルで用いるCO_2 15μm帯放射モデルの再構築と循環への影響(スペシャルセッション「惑星大気の科学」II)
- 大会講演予講集, 2006, Japanese, 日本気象学会A353 H_2O, NH_3, NH_4SH雲を考慮した木星大気の雲対流数値計算(スペシャルセッション「惑星大気の科学」II)
- 大会講演予講集, 2006, Japanese, 日本気象学会A351 回転球面あるいは球殻の縞帯問題 : ロスビー波と平均流加速(スペシャルセッション「惑星大気の科学」II)
- 大会講演予講集, 2006, Japanese, 日本気象学会D406 火星大気大循環モデルで表現される中小規模擾乱の構造(大気力学II)
- Abstracts for fall meeting of the Japanese Society for Planetary Science, 2006, THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, For the purpose of investigating the effects of condensation reactions on the circulation structures of Jovian atmosphere, we have developed a two-dimensional numerical model that incorporates condensation of water and ammonia and production reaction of ammonium hydrogensulfide. We have conducted numerical calculation for a fairly long period covering many life cycles of convective clouds.<BR>The result shows that the vertical profile of stability has two peaks associated with condensation of water and ammonia. The stability of the layer associated with condensation of ammonia is not strong enough to prevent convective upward motion, because the upward motion ranging from the water condensation level to the tropopause appears intermittently.Numerical modeling of moist convection in Jupiter's atmosphere with H2O, NH3, and NH4SH clouds
- 大会講演予講集, 2006, Japanese, 日本気象学会D408 大気主成分の凝結を考慮した火星大気対流モデルの開発(大気力学II)
- 大会講演予講集, 2006, Japanese, 日本気象学会P118 木星大気雲対流モデルの定式化
- Abstracts for fall meeting of the Japanese Society for Planetary Science, 2006, THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Aiming for an atmospheric general circulation model (GCM) with a flexible and readable source code, a dynamical core is newly designed and its implementation tests are performed. In order to improve the flexibility and readability of the model, the source code is hierarchically structured by the use of modules and derived-type variables, array-valued functions are frequently used for operating array-valued variables, a set of naming rules are newly introduced for variables and functions, and a tool set for automatic generation of reference document (RDoc) are improved. The dynamical core developed here is named DCPAM, and is provided at http://www.gfd-dennou.org/ .Development of a general circulation model for planetary atmospheres: the GFD Dennou Club DCPAM
- 日本気象学会大会講演予稿集, Oct. 2005, Japanese, 日本気象学会木星大気対流圏における静的安定度の水存在量に対する依存性
- 大会講演予講集, Oct. 2005, Japanese, 社団法人日本気象学会P123 火星大気湿潤対流のための非静力学モデルの定式化
- 大会講演予講集, Oct. 2005, Japanese, 社団法人日本気象学会P388 ソフトウェアとしての可読性を重視した全球プリミティブモデル
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Sep. 2005, Japanese, Japan Society of Fluid Mechanics, Aiming for an atmospheric general circulation model (GCM) with readability and flexibility, a dynamical core is newly designed and implemented. Readability and flexibility are expected to be increased by the use of advantageous features of Fortran 90 and by proposing a programming style. The programming style is to help us imagine the corresponding equations of the original physical system. The implemented dynamical core is examined by the benchmark test for GCM dynamical core proposed by Held and Suarez (1994). According to the results of 1200 day integration with the horizontal resolutions of T21, T42, and T63, it is confirmed that the Hadley circulation and mid-latitudinal disturbances are well expressed.AM05-13-013 Design and implementation tests of a dynamical core for a general circulation model with a flexible and readable source code
- 大会講演予講集, Apr. 2005, Japanese, 社団法人日本気象学会C104 大気大循環モデルで表現される赤道域降水活動の解像度依存性(熱帯大気I)
- 日本流体力学会年会講演論文集, 2005, Japanese, 日本流体力学会, Aqua planet experiments are performed in order to investigate horizontal and vertical resolution dependencies of equatorial precipitation activities. The numerical model utilized is AGCM for Earth Simulator (AFES). The cumulus convective scheme is not used. With the increase of vertical resolution from 24 to 96 levels, there are not major differences in precipitation pattern. With the increase of horizontal resolution from T39 to T319, the eastward propagating envelope structures of the westward propagating individual grid-scale disturbances become evident.AM05-13-012 A Resolution Dependence of Equatorial Precipitation Activities Represented in a General Circulation Model
- 大会講演予講集, 2005, Japanese, 日本気象学会D309 火星大気大循環モデルで表現されるダスト巻き上げと輸送(大気力学I)
- Abstracts for fall meeting of the Japanese Society for Planetary Science, 2005, THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, Formulation of a non-hydrostatic model for moist convection associated with condensation of major atmospheric component in the Martian atmosphere is examined. When the supersaturation of carbon dioxide is small or the time scal of condensation is longer than that of sound wave, a modified quasi-compressible system in which a mass source term associated with condensation is introduced in the continuity equation can be adapted for the Martian atmospheric moist convection. We develop a 2D non-hydrostatic model based on the formulation of modified quasi-compressible system and investigate flow patterns associated with the Martian atmospheric moist convection with steady thermal forcing.Formulation of a non-hydrostatic model for moist convection in theMartian atmosphere
- Abstracts for fall meeting of the Japanese Society for Planetary Science, 2005, THE JAPANESE SOCIETY FOR PLANETARY SCIENCES, The structure of convective clouds in Titan's troposphere and their role in methane cycle between the atmosphere and the ground surface are investigated using a fluid dynamical model containing parameterized microphysical processes. Cloud convection is driven by a body cooling in the troposphere and heat and methane fluxes from the ground surface. Preliminary result shows the followings: (i) Titan's ground surface must be considerably dry in order to explain the observed methane undersaturation in the lower atmosphere, (ii) even with such dry surface conditiion, cloud convection is active, (iii) most of the methane rain produced in the convective clouds evaporates in unsaturated lower troposphere.Numerical modeling of cloud convection in Titan's atmosphere
- 大会講演予講集, Oct. 2004, Japanese, 社団法人日本気象学会C302 大気大循環モデルで表現される赤道域降水活動の解像度依存性(熱帯大気I)
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Aug. 2004, Japanese, Japan Society of Fluid Mechanics, Aqua planet experiments are performed in order to investigate horizontal and vertical resolution dependencies of equatorial precipitation activities. The numerical model utilized is AGCM for Earth Simulator (AFES). With the increased vertical resolution from 24 to 96 levels, weak precipitation intensity tends to be widely distributed, and the westward propagating grid-scale disturbances become obscured. With the increased horizontal resolution from T39 to T319, the eastward propagating envelope structures of the westward propagating individual grid-scale disturbances become evident.A313 A Resolution Dependency of Equatorial Precipitation Activities Represented in a General Circulation Model
- 大会講演予講集, May 2004, Japanese, 社団法人日本気象学会P122 階層的地球流体力学スペクトルモデル集SPMODEL
- 大会講演予講集, May 2004, Japanese, 社団法人日本気象学会P221 水惑星実験における赤道域降水活動の放射冷却率鉛直分布依存性
- 大会講演予講集, 2004, Japanese, 日本気象学会P107 氷床流動モデルの構築 : 気候モデルへの導入に向けて
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Jul. 2003, Japanese, Japan Society of Fluid Mechanics, GFD Dennou CLub AGCM6 is now being designed as an atmospheric general circulation model that helps us to understand dynamics and to perform a comparative study of the planetary atmospheres. The major target is to develop a software structure which enables us to change the model geometry and to build in or remove physical and/or dynamical processes with ease. For the purpose of considering AGCM6 architecture, we are now reinforcing the SPMODEL library. The SPMODEL library is designed to be a series of spectral models of typical equation systems which appear in the field of geophysical fluid dynamics. The spherical shallow water model of SPMODEL library is now provided and can be utilized for further designing of the dynamical core of AGCM6Development of a general circulation model for the Earth type planetary atmosphere AGCM6
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Jul. 2003, Japanese, Japan Society of Fluid Mechanics, Multiple equilibrium solutions of gray atmosphere are investigated for various values of solar constant. Models used are a three-dimensional primitive model (GCM) and a one-dimensional energy balance model (EBM). Solutions obtained by models are only ice-covered states for small values of solar constant, and only runaway greenhouse states for large values of solar constant. For intermediate values, multiple solutions are obtained, for instance, a combination of ice-covered state, partially ice-covered state and the runaway greenhouse state. The large ice cap instability discussed in previous EBMs also occurs in GCM, since a partially ice-covered state with ice line latitude lower than 20 degree is not obtained. Contrary to results of EBMs, an equilibrium solution in which ice line latitude is 22 degree is obtained in GCM. The solution is maintained by condensation heating near ice line latitude.Dependency of equilibrium states of gray atmosphere on solar constant : from the runaway greenhouse to the snowball states
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Jul. 2003, Japanese, Japan Society of Fluid Mechanics, The initial development of the atmospheric response to a warm SST anomaly placed at the equator is examined by way of an ensemble switch-on experiment with an aqua planet GCM. An ensemble average of the size of 128 satisfactory reduces the transient noise and reveal the character of the response which follows. In a few days after the switch-on of the SST anomaly, a convection center develops, and a global increase of surface pressure occurs as a barotropic response to the heating. The response afterward is consistent with Gill (1980); a warm Kelvin/Rossby wave-like anomaly is emitted to the east/west of the convection center, except that the characteristic wave speed is that of moist gravity waves. After several days, precipitation is intensified/suppressed to the east/west of the SST anomaly because of the surface frictional convergence/divergence caused by relative low/high pressure anomaly along the equator in the Kelvin/Rossby wave-like response.Tropical Precipitation Patterns in Response to a Local Warm SST Area : an Ensemble Aqua Planet Study
- 大会講演予講集, May 2003, Japanese, 社団法人日本気象学会B153 灰色大気の平衡状態の太陽定数依存性 : 暴走温室状態から全球凍結状態まで(力学を介しての横断的理解)
- 大会講演予講集, 2003, Japanese, 日本気象学会B152 大気大循環モデルを用いた火星大気大循環の数値計算(力学を介しての横断的理解)
- 大会講演予講集, Oct. 2002, Japanese熱帯大気の暖水域に対する応答 : アンサンブル水惑星実験による時間発展の抽出
- 日本惑星科学会秋季講演会予稿集, Oct. 2002, Japanese, THE JAPANESE SOCIETY FOR PLANETARY SCIENCES鉛直対流により励起される火星大気の内部重力波
- Proceedings, ... meeting of Japan Society of Fluid Mechanics, Jul. 2002, Japanese, Japan Society of Fluid Mechanics, A set of spectral models suitable for performing standard numerical experiments of geophysical and planetary fluid dynamics problems is developed. Our policy for the development of the program codes is, 1) anyone can read, use and modify the source programs; 2) the sources programs should be so understandable that anyone can re-build and modify the programs; 3) visualization and post-processing should be performed easily. For the first and second requirements, Fortran90 modules for spectral models are prepared by wrapping the subroutines of ISPACK Fortran77 library. The programs can be clearly understandable, since they can be written in a similar form to the mathematical expressions with the help of a systematic function naming and array handling features of Fortran90. The self descriptive data format 'gtool4' is used for output to satisfy the third requirement. Commands for simple post-processing of gtool4 data, such as visualizing and arithmetic operations, are also developed.Simple numerical GFD experiments by use of spectral models constructed with ISPACK and gtool4
- 日本気象学会大会講演予稿集, May 2002, Japanese動画と音声を用いた研究公開/教育システムの構築
- 日本気象学会大会講演予稿集, May 2002, Japanese木星型惑星大気の熱力学計算 温度分布と静的安定度の分布
- 日本気象学会大会講演予稿集, May 2002, Japanese鉛直対流により励起される火星大気の内部重力波
- 大会講演予講集, May 2002, Japaneseすべての気象データに使えるデータベースの要件 : gtool4プロジェクトを通じて見えてきたもの
- Abstracts for fall meeting of the Japanese Society for Planetary Science, 2002, THE JAPANESE SOCIETY FOR PLANETARY SCIENCESNumerical simulation of cloud convection in the atmosphere of Titan: A preliminary study
- 日本流体力学会年会講演論文集, 2002, Japanese, 日本流体力学会, A numerical simulation is performed by using a two-dimensional anelastic model for clear sky condition to investigate the possible characteristics of internal gravity waves generated by thermal convection in the Martian atmosphere. The results show that the vertical and horizontal wave length of simulated internal gravity wave are 10km and 10∿ 15km, respectively. The resultant time series show that the vertical phase velocity are about 10m/sec. According to the dispersion relationship of internal gravity wave, the vertical group velocity become about several m/sec. The horizontal mean value of "effective vertical diffusion coefficient", which is the vertical diffusion coefficient when the vertical diffusion is only responsible for the heat flux, has the same order of magnitude of that used by the 1D photochemical model. The result suggests that the internal gravity wave generated by thermal convection in the Martian lower atmosphere contributes to the vertical mixing in the Martian middle atmosphere.A numerical simulation of internal gravity wave generated by thermal convection in the Martian atmosphere
- 大会講演予講集, Oct. 2001, Japanese全球凍結条件に関する数値実験 : 多重平衡解についての検討
- 日本惑星科学会秋季講演会予稿集, Oct. 2001, Japanese木星型惑星大気の熱力学計算 大気の静的安定度に関する考察
- 日本気象学会大会講演予稿集, May 2001, Japanese木星型惑星大気の熱力学計算
- 大会講演予講集, Oct. 2000, Japanese灰色大気に覆われた惑星の全球凍結条件
- 大会講演予講集, Oct. 2000, Japanese多次元数値データの自己記述的入出力ライブラリ gtool4/Fortran90 の開発 : Fortran 90 モジュール構成と移植性
- 大会講演予講集, May 2000, Japanese火星大気大循環の計算機シミュレーション : 子午面循環における地形の影響
- 大会講演予講集, May 2000, Japanese多次元数値データの自己記述的格納形式 gtool4 の開発
- 大会講演予講集, Nov. 1999, Japanese回転球面浅水系乱流実験における赤道ジェット形成について
- 大会講演予講集, Nov. 1999, Japanese火星大気放射対流の数値計算
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Nov. 1999, Japanese, The Japanese Society for Planetary SciencesP409 Numerical simulation of moist convection in Jovian atmosphere : sensitivity to vertical wind shear
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Nov. 1999, Japanese, The Japanese Society for Planetary SciencesP412 A numerical simulation of Martian atmospheric convection driven by radiative forcing
- 年会一般講演, Jul. 1999, JapaneseResponse of the Tropical Atmosphere to a Localized Warm SST Area: Time-Development Observed in an Aqua-Planet Experiment
- 大会講演予講集, Apr. 1999, Japanese火星大気対流の数値計算 : 日変化的強制に対する応答
- 12TH CONFERENCE ON ATMOSPHERIC AND OCEANIC FLUID DYNAMICS, 1999, English, AMER METEOROLOGICAL SOCIETYTwo-dimensional turbulence on a rotating sphere with high-resolution spectral model
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Oct. 1998, Japanese, The Japanese Society for Planetary Sciences101 Emergence of circumpolar vortex in 2-D turbulence on a rotating sphere
- 大会講演予講集, Oct. 1998, Japanese回転球面上の減衰性2次元乱流における周極渦の形成
- 年会一般講演, Jul. 1998, JapaneseNumerical Simulation of Martian Atmospheric Convection
- 大会講演予講集, May 1998, Japanese火星大気対流の数値計算 : 地表付近の分解能依存性
- 大会講演予講集, Oct. 1997, Japanese火星大気の対流計算
- 大会講演予講集, Oct. 1997, Japanese木星大気の対流運動の数値計算(3)
- 大会講演予講集, Oct. 1997, Japanese3次元大気の暴走限界 : 日射分布と回転の効果
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Sep. 1997, Japanese, The Japanese Society for Planetary SciencesP418 Finite amplitude convection in rotating spherical shells and induced mean zonal flows
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Sep. 1997, Japanese, The Japanese Society for Planetary Sciences603 The runaway limit of three-dimensional atmospheres : the effects of solar radiation distribution and rotation
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Sep. 1997, Japanese, The Japanese Society for Planetary Sciences606 Numerical simulation of convection in Martian lower atmosphere
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Sep. 1997, Japanese, The Japanese Society for Planetary Sciences705 Numerical simulation of moist convection in Jovian atmosphere
- 年会一般講演, Jul. 1997, JapaneseNumerical Simulation of Jovian Cloud Convection
- 年会一般講演, Jul. 1997, JapaneseThe energy transport of the gray atmospheres with increased solar flux
- 年会一般講演, Jul. 1997, JapaneseThe Effects on the Tropical Precipitation Patterns due to a Local Warm SST Area Placed at the Equator of an Aqua Planet
- 大会講演予講集, May 1997, Japanese太陽定数増大時の南北温度差
- 大会講演予講集, Nov. 1996, Japanese熱帯域にある局所的な暖水域が熱帯降水分布に与える影響
- 大会講演予講集, Nov. 1996, Japanese3次元灰色大気の暴走限界
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Oct. 1996, Japanese, The Japanese Society for Planetary Sciences501 The integration of the runaway greenhouse state and determination of the runaway limit
- 年会一般講演, Jul. 1996, JapaneseLong Term Integrations of Runaway Greenhouse States
- 大会講演予講集, May 1996, Japanese暴走温室状態の長時間積分
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Nov. 1995, Japanese, The Japanese Society for Planetary Sciences402 The heat budget in the runaway greenhouse state
- 大会講演予講集, Oct. 1995, Japanese暴走温室状態における熱収支
- 大会講演予講集, May 1995, Japanese暴走温室状態にも適用可能な3次元モデル開発
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Oct. 1994, Japanese, The Japanese Society for Planetary Sciences251 Numerical simulations of the runaway greenhouse : comparison betwenn the 1D and 3D systems
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Oct. 1993, Japanese, The Japanese Society for Planetary Sciences213 Boussinesq convection in rotating spherical shells : a study on the equatorial superrotation
- Abstracts Fall Meeting of the Japanese Society for Planetary Sciences, Oct. 1993, Japanese, The Japanese Society for Planetary Sciences206 Numerical simulations of an atmosphere with a condensable component as the major element
■ Research Themes
- 文部科学省, スーパーコンピュータ「富岳」成果創出加速プログラム, Apr. 2023 - Mar. 2026シミュレーションとAIの融合で解明する宇宙の構造と進化
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S), Grant-in-Aid for Scientific Research (S), Kobe University, 26 Jun. 2019 - 31 Mar. 2024データ同化に向けて「あかつき」観測データを精錬、雲追跡風ベクトル場を生成し、そこから大気諸相の特徴を抽出すること、および、データ同化試行実験を開始するとともに、データ同化の有効性を検証することに注力して研究を進めた。 大気諸相の特徴を抽出する研究で得られた成果の１つは雲層低緯度でのスーパーローテーションの維持機構を史上初めて観測から定量的に明らかにしたことである。「あかつき」撮像データからの雲追跡風ベクトル場と雲頂温度場、さらに、過去の探査機データをも活用し、各種大気波動による角運動量輸送量を求めることに成功した。低緯度の角運動量分布極大の維持には大気熱潮汐波による角運動量輸送が支配的であり、過去の研究で示唆されてきた大規模な乱流や熱潮汐波以外の波動による輸送は弱くむしろ逆に働いていた。この結果は今後のデータ同化実験に供され、得られた同化データの解析によってこれをもたらす循環構造が解明されていくことが期待される。 データ同化の有効性を検証する研究の成果の１つは、同化実験における雲層上端の惑星規模ケルビン波の再現可能性を示したことである。金星大気の紫外線画像には顕著なY字模様が見えるが、これを維持する構造として雲層上端に惑星規模赤道ケルビン波が想像されてきた。しかし、金星大気モデルで雲層上端にケルビン波を再現した例はこれまで報告されていなかった。この問題に対して、雲追跡風ベクトルを模した疑似観測データを与え、データ同化による観測システムシミュレーション実験を行い、雲層上端の赤道域南北15度の範囲で6時間ごとの風速データがあれば、ケルビン波がデータ同化により表現できることがわかった。「あかつき」観測の中に雲層上端のケルビン波をとらえているデータが存在すれば、モデルの不完全性を観測が補完し、あるいは、不完全性の原因を追求できる可能性があることを示した。
- 文部科学省, 高性能汎用計算機高度利用事業費補助金「「富岳」成果創出加速プログラム」, 神戸大学他, Apr. 2020 - Mar. 2023, Coinvestigator宇宙の構造形成と進化から惑星表層環境変動までの統一的描像の構築
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A), Grant-in-Aid for Scientific Research (A), Kobe University, 01 Apr. 2019 - 31 Mar. 2020A study on the atmospheric circulation of Venus by the use of AKATSUKI data assimilation本研究のコアである、地球シミュレータ上で最適化された大気大循環モデルAFESを核とした金星大気大循環モデルAFES-Venusの開発と数値実験ならびにそれを用いたデータ同化試行を進めた。特に、金星大気データ同化システム（ALEDAS-V）の実装検証としては、欧州の探査機 Venus Express から得られていた風速データを同化し金星大気熱潮汐波の位相修正への効果を吟味し、大気大循環に大きな影響を与えることを最終的に確認、これを発表した。一方、データ同化を活用した観測計画実証として、複数の小型衛星による電波掩蔽観測を想定した擬似観測データをデータ同化することにより金星大気高緯度の特徴的構造であるコールドカラーの観測可能性を検討、２－３機の小型衛星による多点観測により意義のある観測が実現できることが検証され、データ同化による金星大気観測設計の可能性が示された。 また、「あかつき」観測からの知見の集積に関しては、「あかつき」冬季集中観測の結果の集計に着手し、画像データから雲風ベクトル解析を進めるとともに、これまで得られてきた雲追跡風ベクトルの統計こよって得られた知見をもとに、金星大気の子午面循環とスーパーローテーションに関する理論的・数値的研究を進め、特に、TEM数値モデル（変換オイラー平均子午面循環=擾乱による統計的な輸送を考慮した比較的単純な理論的循環モデル）の上にこれらをまとめて解釈することを試み、これを発表するとともに、今後の研究の理論考察の対象、すなわち、子午面循環構造に対する仮説の一つとしてこれを位置づけた。
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (A), Japan Aerospace EXploration Agency, 01 Apr. 2016 - 31 Mar. 2020Unveiling the material circulation in the Venusian atmosphere with coordinated spacecraft and ground-based observationsThe atmospheric material circulation on Venus related to cloud formation has been studied by cooperative observations by Akatsuki spacecraft and ground-based telescopes and numerical modeling. We have clarified the structure of the mean meridional circulation and the characteristics of various planetary-scale waves, which may be related to the maintenance of the high-speed zonal flow, by cloud tracking using infrared images covering the whole local time as well as ultraviolet images. We obtained observational clues that angular momentum transport caused by thermal tides contributes to the maintenance of high-speed zonal winds. For integrating observational data with numerical modeling, data assimilation was successfully conducted. The global temperature structure was observed by radio occultation. The cloud physics was introduced into the atmospheric general circulation model, and the distribution of sulfuric acid clouds consistent with the observations was reproduced.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Young Scientists (B), Kobe University, 01 Apr. 2016 - 31 Mar. 2019Exploration of superrotation by development of hierarchical numerical models of planetary atmospheric circulationTowards the understanding of Venusian fastly rotating atmosphere, superrotation, hierarchical numerical models for atamospheric dynamics and geophysical fluid dynamics have been developed. I found a strong dendence of large-scale numerical results on numerical methods from preliminary experiments using existing atmospheric general circulation models. To understand such numerical dependence and to develop the hierarchical models, I developed an environment for experimental numerical calculations by using a scripting programing language Ruby and published as a library.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), The University of Tokyo, 01 Apr. 2016 - 31 Mar. 2019Radio occultation observation data of Venus was analyzed by radio holography method to improve the vertical resolution, and universal existence of waves and neutral layers with vertical scales of several hundred meters were revealed. Sharp inversion layers were also found to exist at the top of high latitude convection layers. We also carried out numerical simulations of the convective layer with high vertical resolution and a wide computational domain, and reproduced the convective motion and the gravity waves excited by convection. Breaking of gravity waves is suggested to be caused by shear instability and convective instability. Furthermore, we could understand the height of breaking of gravity waves and the amplitude of gravity waves in comparison with the observational results of radio wave occultation observation.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kyoto University, 01 Apr. 2012 - 31 Mar. 2017Jet formation process on a beta plane and a rotating sphere was studied theoretically and numerically for incompressible two-dimensional fluids. The jet formation is observed in several situations including Jovian atmosphere, but its dynamical mechanism is not yet well understood. In this study, we have obtained an analytical description for the amount of jet acceleration on the beta plane by the use of the pseudo momentum given by the weakly nonlinear theory of Rossby waves, employing asymptotic forms of the eigenfunctions of the continuous modes in the linear stability problem of the jet flow. We also performed a numerical simulation of the fluid equation, and obtained a good agreement between the theoretical prediction and the numerically observed values for the jet acceleration.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), Hokkaido University, 01 Apr. 2011 - 31 Mar. 2016Evolution of steam atmospheres on earth-like planets after each final giant impact event is theoretically solved with an analysis of its observability. Two types of evolutionary tracks are found: one is the rapid formation of a water ocean and another is the long-term persistence of the magma ocean state. The secular loss of surface water due to atmospheric escape driven by stellar UV irradiation may rather stabilize surface liquid water than merely produce an arid surface environment. General circulation experiments provided with various boundary conditions reveal that a synchronously rotating planet and a land planet may have wider habitable zones than previously thought. Numerical models to solve cloud convection and radiative transfer in gas giant planets are also developed, revealing the mechanisms for the intermittencies observed for cloud convection in the solar system gas planets as well as roles of cloud layers on controlling the thermal emission from gas giant atmospheres.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A), Grant-in-Aid for Scientific Research (A), Japan Aerospace Exploration Agency, 01 Apr. 2010 - 31 Mar. 2014The mechanism of the atmospheric circulation and the transport processes of atmospheric constituents were studied by analyzing observational data taken by Venus Express and ground-based observations. The data were processed using the data analysis softwares developed for the Japanese Venus arbiter Akatsuki, which will be inserted into a Venus orbit in 2015. The analysis revealed various aspects of the atmosphere, such as three-dimensional structures of planetary-scale waves, dissipation of gravity waves at high altitudes, complicated vertical distributions of the upper haze layer, latitudinal and local-time dependence of the cloud height, and long-term variations of the cloud albedo. Numerical simulations, and the observed features were compared with those model results to understand the mechanism. These studies clarified remaining issues to be solved, such as the role of meso-scale processes, chemical processes governing the cloud albedo, and the mechanism of climate variation.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kobe University, 2009 - 2011, Principal investigatorComprehensive analyses are made on the output from the general circulation model experiments under idealized lower boundary conditions in the Aqua-Planet Experiment Project(APE), which was participated by 14 modeling groups aiming at climate studies or numerical weather prediction in the world. The results demonstrate a great variety among the structure of tropical precipitation disturbances simulated in the participating models, both in wavenumber space and in real space. In addition, new theoretical insights are obtained, one of which concerns the spectral property of the hierarchical rainfall structure and another concerns the variety of large-scale atmospheric response to a localized sea surface temperature anomaly placed on the equator.Competitive research funding
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research, Grant-in-Aid for Challenging Exploratory Research, Kobe University, 2009 - 2011, Principal investigatorWe examine formulation of the governing basic equations that describe developments of a protoplanetary accretion disk, and discuss applicability of various concepts of geophysical fluid dynamics to its fluid motions, and reconsider the structures of basic fields and disturbances. We confirm that the condition that should be satisfied by axisymmetric fields of geophysical fluid dynamics should be satisfied also for the nebula gas fields of protoplanetary accretion disk. However, it seems that the structure of disturbances is quite different from that of baroclinic unstable disturbances of geophysical fluid dynamics.Competitive research funding
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kyoto University, 2008 - 2011Thermal convection in a rotating spherical shell, typical in earth and planetary sciences, is studied with an attention focused on its dependence on the angular velocities of the inner and the outer boundaries and on the temperature difference between the boundaries. The bifurcation diagram is obtained, where the zonal phase velocity of the convection pattern is found to change its direction, and its physical interpretation is given in terms of the vorticity dynamics and weakly nonlinear theory. Dynamical interaction between the boundaries and the fluid is also studied to find the differential rotation and chaotic behaviors of the boundaries.
- 日本学術振興会, 科学研究費助成事業 特定領域研究, 特定領域研究, 北海道大学, 2009 - 2010地球科学データの高度利用と流通のための基盤開発近年の地球観測と計算機の進展により,大気や水,環境汚染物質などの数値データは爆発的に増加しており,対応が急務である.我々は18年度より,検索,解析,可視化機能に富み,個人や小グループによるデータ整理や研究遂行からWebでの多機能なデータ公開サイト構築までをシームレスに支える,新しいタイプのソフトウェアGfdnaviを開発してきた.本研究課題は,これをさらに発展させ,次を実現することを目的として実施した.(1)データから得られた知見を文書化する機能を発展させ,科学データ,データ解析プロセスと有機的に結びついた形での知識の集積を可能とする.(2)Gfdnaviサーバ間のオーバレイネットワークを実用化する.(3)実用性をさらに向上させる.本年度は以下の成果を得た. 昨年度に提案及び基本実装を行った「スクリプティングによる逐次アクセスと親和的なRESTful webサービス」を強化した.これにより,オブジェクト指向スクリプト言語Rubyにおいて地球流体の研究者がローカルデータの解析に用いるライブラリとWebサービスのクライアントライブラリの統合が進んだ.さらにデータから得られる知見を文書化する機能のAPIを完成し,大量のデータ処理から文書を自動生成できるようにした.(目的(1),(3)) Gfdnaviサーバ間のネットワークのハブとなるサーバを開発し,運用を開始した.その過程でピアツーピア環境におけるファセット検索実現に掛かる新手法を提案した.(目的(2)) データ解析可視化基礎ライブラリの強化:Gfdnavi等で用いられている,地球流体データ解析・可視化のための基礎ライブラリGPhysを強化し,適用範囲を広げた.(目的(3))
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Kyoto University, 2005 - 2008外側に安定成層を伴う回転球殻内の熱対流および磁気対流ダイナモの数値実験を通じて, 以下のような流れの性質が新たに見いだされた.1)安定成層内での2次元的な乱れた流れは極周辺に西向きジェットを形成し, その強さと幅は回転角速度の1/4および-1/4乗に比例する.2)強い安定成層の存在によって, 対流運動が生成する赤道外側領域での帯状流は回転とは逆向きになる.3)回転軸に平行な磁場の存在は対流運動の安定成層への貫入を助長する.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A), Grant-in-Aid for Scientific Research (A), 2007 - 2007, Principal investigatorFor the purpose of investigating the interplay among dynamical, thermal, and compositional structures of the atmospheres of Jovian planets, we compiled the current status of corresponding knowledge, developed a hierarchical modeling system, and conducted numerical experiments with those hierardical modeling systems. The main findings of our investigations are summarized as follows: 1. We developed a vertical one-dimensional equilibrium cloud condensation model, which enable us to cover possible atmospheric compositional varieties of the Jovian planets. We found that the contributions to the intensity of stability by the cloud layers associated with the condensation of NH_3 and formation of NH_4SH are not negligible compared with that of H_2O. 2. We developed a two-dimensional cloud convection model incorporating the condensation of NH_3 and H_2O and formation of NH_4SH. We conducted a series of numerical experiments, and found that the H_2O condensation level acts as a distinct dynamical boundary that separates the convective motions above and below it. The stable layers due to NH_3 and NH_4SH clouds cannot suppress the cloudy plumes driven by H_2O condensation healing, resulting in the mixing over the full depth of the atmosphere above the H_2O condensation level. 3. With the application to the Jovian atmosphere in mind, we performed a series of numerical studies on the equatorial acceleration using the three dimensional Bousinesq spherical shell convection model. We found that a strong stable layer in the outer layer helps the development of equatorial retrograde jet. This result may raise a question about the theory where rotating spherical thermal convection explains the cause of the equatorial westerly jets of Jupiter and Saturn. 4. A common software infrastructure, over which those numerical models were constructed, was developed. It contains "gt4f90io" which is a library for I/O of numerical data, and "Rdoc" which is an automatic documentation generator for numerical model codes. We also organized a standard style of Fortran90 programming and constructed a library of Fortran90 functions for basic mathematical manipulations, with which we developed 'Spmodel" which is a set of spectral models. All of the softwares mentioned are open to public on our web site.Competitive research funding
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), Kyoto University, 2004 - 2007Flow patterns governed by fluid equation in earth sciences-numerical study from view points of dynamical systems-Flow pattern formation is studied in the framework of fluid equations employed in earth sciences, especially of the 2D Navier-Stokes equations on a rotating sphere. When the flow region is a whole sphere, westward circumpolar jets are observed to emerge from turbulent initial conditions. A scaling law is proposed for the strength and the width of these polar jets, which shows that the whole energy of the flow field is absorbed in these jets in the limit of large rotation rate. The zonal jet formation is also studied in the case of shallow water equation, where the jets emerge in the equatorial region rather than the polar regions. When the flow region is a rotating hemisphere, the boundary of which coincides with meridional lines, the westward intensified flow emerges under the forcing of zonal winds. The lstability of the westward intensified flow on the rotating hemisphere is studied, and the critical Hopf mode is found to have the largest amplitude near the point where the boundary flow leaves the west boundary. Flow pattern and its stability are studied also in a rotating polar cap, a circular bounded region with the center at the north pole and with inlet and outlet on the boundary. While in the linear solution the inlet flow goes through all the flow region, there emerges an isolated vortex in the central region near the north pole, and this nonlinear flow becomes unstable as the inlet flow rate is increased. In some chaotic dynamical system with small degrees of freedom, averaged dynamical quantities over unstable periodic orbits are studied especially when the period of the periodic orbits is large. Numerical results show that statistical properties of the orbital averages along the unstable periodic orbits agree with those along chaotic orbits in, for example, 1D map, but do not in 2D map or in some systems of ordinary differential equations.
- 日本学術振興会, 科学研究費助成事業 特定領域研究, 特定領域研究, 京都大学, 2006 - 2006多次元・多重な地球環境データの管理と高度利用近年の地球観測と計算機の進展により、大気や水、環境汚染物質などのデータは爆発的に増加している。本課題は、これら「地球流体」データの情報爆発問題に対処し、専門研究者や環境対策・防災等のための利用者にむけて使いやすい形でデータを提供し、さらに手持ちデータも含めて解析可視化できるような仕組みとシステムを開発することを目的として遂行した。その結果、研究者各人や小グループのデータアーカイブ、解析、可視化から、一般向けの(解析可視化可能な形での)データ公開までをシームレスにサポートする、これまでにない新しいツールGfdnaviを成功裏に開発した。 Gfdnaviは、これまでに我々が開発してきた、オブジェクト指向言語Rubyによる地球科学データ解析可視化ライブラリ群と、包括的なWebアプリケーション開発フレームワークRuby on Railsを組み合わせて実現した。本課題では、以下の研究・開発を行い、いずれもGfdnaviに取り込む形で実用化した。 ●地球科学データのメタデータの自動抽出と階層的な関係データベース化 ●キーワード及び時空間情報による検索、地図を用いた検索 ●数値データの解析可視化ユーザインタフェース ●解析可視化基盤ライブラリの強化 さらに、今後の展望を踏まえて、次の研究を行った。 ●P2Pによるオーバレイネットワークの構築と分散ハッシュを用いた横断検索 ●データから得られる知見情報をもとデータと有機的に関連づけて保存することによる知識ベース化の基礎検討 なお、Gfdnaviはhttp://www.gfd-dennou.org/arch/davis/gfdnaviにて公開している。
- 日本学術振興会, 科学研究費助成事業 基盤研究(C), 基盤研究(C), 北海道大学, 2004 - 2004地球流体力学の知見情報をインターネット上に集積公開して行くための調査研究予備的な国内検討会を実施後,米国への調査旅行を企画し,UNIDATAならびPrinceton大のGFDL/NOAAを訪問,情報技術の進展とそれによる当該分野の教育・研究活動への影響等に関して意見交換を行った.調査の結果を受け,さらに国内検討会を開催し,現在の情勢と当該分野でなされるべき今後の対応について議論を進めた.これらの資料は「地球流体電脳倶楽部」のWEBサーバ上に掲載し公開されており,http://www.gfd-dennou.org/arch/davis/workshop/から適宜たどることができる. UNIDATAは1983年に設立され,米国の大気科学関連大学連合によって運営される,当該分野の研究教育のための情報基盤を支えるための組織である.データのアーカイブ,必要となるファイル形式の提供(netCDF),データハンドリングと可視化ツールの開発と提供で知られており,また,様々な情報技術開発のコーディネーションを行う.現在,UNIDATAが中心となって,各地に分散しているデータサーバをインターネット上に統合,一つの仮想的なデータベースとして機能せしめ,情報をリアルタイムで提供(OPeNDAP/THREDDS),数値予報モデルと有機的に組み合わし,研究のみならず教育の現場で利用する実験が進められている.残念ながらわが国では気象業務法の縛りがあり,かつ,気象庁が研究教育活動に対してデータを提供する枠組の整備が不十分で,同種の試みを実行することは不可能である.様々な制度がインターネット以前の時代のままであることが問題であり,情報基盤構築をリードするUNIDATAのような組織がないことが状況の改善を困難にしている.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), 2001 - 2003Flow Pattern Formation in Turbulence on a Rotating Sphere.Fluid motion on a rotating sphere often shows pattern formation phenomena never observed in a planer motion because of the influence of the compactness of the flow domain and the differential rotation, and is strongly related to fundamental properties of geophysical flows. Mainly in this project, we studied flow pattern formation arising from turbulent initial conditions, and related problems in fluid dynamics and numerical analysis. We first studied 2D fluid motion in a circular domain on a rotating sphere, and found that in the case of southern hemisphere with the rigid boundary at the equator, eastward circumpolar flow is spontaneously formed, in contrast with the whole sphere case where westward circumpolar jets emerge. The momentum transfer by the Rossby wave is important in this process, and we gave a theoretical description for the jet formation in the frame of weakly nonlinear theory. Instability of westward intensified flows were also studied with the strength of the forcing wind being a bifurcation parameter. A Hopf-type instatility followed by a supercritical bifurcation, is found as the forcing wind increases, and a relation between the instability and configuration of gyres is discussed. Phase change of water is an important factor of general circulation on the earth, and we study flow patterns generated by moist convection and its relation to global circulation from a view point of active rainfall area in tropical zone. Numerical methods are quite important in these studies, and we prepared several types of computer codes for numerical simulation, and also proposed some new numerical methods for a fluid equation on a sphere using a conformal projection to a planer disk, and also for fluid equation on a bounded domain by using a, spectral method with Jacobi polynomials. Mathematical properties of fluid equation related to turbulence dynamics are also studied.
- 日本学術振興会, 科学研究費助成事業 萌芽研究, 萌芽研究, 北海道大学, 2001 - 2003対流渦の直接数値計算による惑星CO_2大気の光化学安定性に関する研究今年度はこれまでの火星大気二次元対流計算の延長線上に計算領域の拡張と放射・光化学プロセスの導入を試みた. 計算領域の拡張は,分解脳100mを維持したまま,まず鉛直方向に高度100kmまで拡張することを行い,ついで水平方向にできるだけ広い領域を並列計算技術等を用いて確保することとした.これまでの計算により,対流圏の鉛直対流によって生成される重力波は高度とともにその卓越波数が小さくなることがわかっており,高高度領域での内部重力波による混合の影響を計算するためには同時に水平方向にも十分な計算領域が必要となる. 領域拡張において判明したことは,これまで我々が用いてきた非弾性方程式系の問題点である.非弾性系では音波を含まないため,圧力を求める際には楕円型の微分方程式を解く必要があったが,これは並列化計算における効率を低下させる要素となる.我々は数値コードを再検討した結果,基礎方程式系の見直しを行い新たに音波を考慮した準圧縮方程式系に基づく対流数値モデルの開発を行うことにした.開発中のモデルと関連文書はhttp://www.gfd-dennou.org/arch/deepconv以下に公開している. 放射・光化学プロセスの導入に関しては極めて単純な二酸化炭素の吸収射出ならびに二酸化炭素の光分解過程を組み込み,高高度での物質分布の時間発展を追うことにした.高高度領域を確保するべく水平32kmの狭い領域に限定し,非弾性系モデルを用いた予備的な計算を実行した.残念ながら,二酸化炭素の光分解に対して重力波の砕破混合が働き分解を阻害する傾向を見極めるための十分なパラメタ実験を行うまでには到らなかった.今後準圧縮方程式系によるモデルを用いて計算を継続する予定である.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), HOKKAIDO UNIVERSITY, 2000 - 2002Research on precipitation activities and atmospheric circulations in the tropics with ensemble aqua planet experimentsFor the purpose of investigating the embedded dynamical structures in the varieties of distributions of precipitation activities and atmospheric circulations generated in response to the inhomogeneity of the sea surface temperature (SST) distribution, we have performed numerical experiments by the use of a general circulation model (GCM) uder the aqua-planet condition where all the surface is covered with the ocean, and we developed software tools for these experiments. Our major results are summarized in the following three points. Firstly, for the purpose of examining the causality of the atmospheric response to a warm SST anomaly placed at the equator, an ensemble switch-on experiment is conducted to reduce the transient noise caused by both individual small scale convective activities and large scale intraseasonal variabilities. It is demonstrated that, to the east of the warm SST area, precipitation increases because of the equatorial surface frictional convergence associated with the Kelvin wave like response, while to the west of the warm SST area, precipitation decreases because of the equatorial surface frictional divergence associated with the Rossby wave like structure. Secondly, for the sake of efficient analyses of the massive data produced by aqua planet experiments, a data structure for multi-dimensional large-size data is designed and a library, gtoo14 Fortran90 library, is developed for handling the data with the proposed structure. Numerical data are stored in netCDF files so that data is independent of machine architecture and is transparent through network. The data structure is summarized as gtoo14 netCDF convention, which is a convention of metadata including information for visualization. Thirdly, a series of preliminary aqua-planet experiments are performed to investigate the precipitation responses to various SST distributions. For the cases with two warm SST areas placed at the equator, it is shown that the resonses can be recognized by the equatorial wave theory. For the cases with sinusoidal SST anomaly at the equator, there emerges a locality of the appearances of estward propagating precipitation structures and westward propagating precipitation structures. For the cases with a warm SST area in the off-equatorial region, there appears a band of precipitation which can be recognized as subtropical convergence zone.
- 日本学術振興会, 科学研究費助成事業 萌芽研究, 萌芽研究, 東京大学, 2000 - 2002流体方程式の球面上の円領域に適合した数値解析法の開発とその応用球面上で円形の剛体境界を持つ領域における流体方程式の数値解法を作成するため、これまで、等角写像(ステレオ写像)を用いて領域を平面上の円盤領域に写像し、その上で直交多項式を用いてNavier-Stokes方程式を解く方法を開発してきた。この手法は、円領域の位置を大きさを自由に設定でき、流体方程式の形をほとんど変形することなく扱える利点があるため、平面上の領域における流体方程式のための数値スキームを応用できるという特徴を持っている。この数値解法の応用としては、たとえば、地球や惑星の大気・海洋を念頭において、回転する球面上における流れのパターンの研究などがある。しかし、平面円盤上も含め、このような極座標系による扱いでは、中心における特異性が問題となることがあり、特に、流体方程式のように微分階数の高いものは、高階微分における不連続性の発生に注意する必要がある。そこでここでは、このような不連続性を避けるため、直交多項式展開における多項式の組み合わせを注意し、いくつかの事例で実際に数値計算して検討した結果、粘性項の中心原点における発散を許しても、流れの全体的な振る舞いへの影響は少ないことを見出した。これは、直交多項式の組み合わせはそれほど複雑でない範囲で扱うことが可能であることを意味しており、この方法を用いて、回転球面における乱流の数値実験を実行した。しかし、このような特異性を完全に除くには、特定の多項式(Jacobi多項式)を用いたスキームを採用する必要があり、このようなスキームについて協力者の石岡圭一氏(東大数理科学)らと検討した。
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), HOKKAIDO UNIVERSITY, 2000 - 2001Observation of Jovian Visible Aurora and its Generation MechanismWe have built an optical observation system of Jovian visible aurora and airglow, which consists of CCD and narrow band filter on ground-based telescope. The emissions have never been measured from ground. We have carried out the observations by use of Rikubetsu 110cm telescope, lidate 60cm telescope and Hokkaido University 10cm telescope from 1999 to 2001. We have also developed an imaging processing system that analyzes the image of Jupiter taken with short exposure time and integrated. We found some emissions in the northern region of Jupiter. Our system may be able to apply to detect very weak signals from planets or airglow. We have investigated theoretically the atmosphere of Jupiter as well as Venus, Earth and Mars. The results suggested that the interactions with clouds and plasma are important to planetary atmospheres. Especially, at high altitudes the ion-drag effect must be considered in the planetary upper atmospheres.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)., Grant-in-Aid for Scientific Research (B)., University of Tokyo, 1998 - 2000Flow Pattern of Thermal Convection of Boussinesq Fluid with Phase Change of WaterThermal convection is studied for Boussinesq fluid which including a material which undergoes a phase change between gas and liquid. The gas-liquid phase change in nature acts as an internal heat budget of the fluid, and simultaneously makes the amount of the material decrease through 'rainfall'. But in this study we focus our attention on the first aspect of the phase-change. We formulate the system in a simplest form, and perform a parameter-survey for the latent heat and a characteristic time of the phase change, in a supercritical state of Benard convection, in where two-dimensional role convection is steady and stable. Numerical study shows that as the characteristic time of the phase change decreases, the convection-cell size first becomes larger and then turns to decrease. The increase of the latent heat is found to support this variation of the cell-size. The variation of the cell size is confirmed by stability analysis. The flow pattern of moist convection in geophysical situation, the interaction of thermal convection in a rotating spherical shell with magnetic field, and two-dimensional flow patterns on a rotating sphere are also studied.
- 日本学術振興会, 科学研究費助成事業 基盤研究(C), 基盤研究(C), 北海道大学, 1999 - 1999惑星大気研究を推進させるための基礎調査21世紀における大気圏・電離圏・磁気圏物理学の一つの目標である,地球・惑星大気圏の基本的成り立ちや構造・力学・大気と太陽風の相互作用さらに生命圏としての惑星大気に関する普遍的・本質的理解へ向けて,現時点での既存知識・理論的枠組・観測手段などを集約・整理し,問題点を明らかにすることにより惑星探査を含む惑星大気研究の将来像を探るための基礎調査を実施した.以下のような5項目について,それぞれの研究の現状と今後の動向を集約・検討した. 惑星上昇大気と太陽風との相互作用: 上層大気の惑星空間への散逸,逆に惑星空間から惑星大気への物質流入,太陽変動に対する惑星大気の応答,太陽風との相互作用などに関与する電磁気的素過程 惑星大気光化学: 惑星大気圏内で放射や相変化などエネルギー収支に関与する諸物質の,生滅を支配する光化学的素過程,ならびに輸送を支配する力学的素過程 惑星大気力学: 超高速気流の生成・維持のメカニズム,濃密(高圧高温)大気の力学など,地球上に存在しない特性や振舞をする大気に関する力学的枠組の構築 惑星大気の起源: 各惑星大気の組成・構造の分化したプロセスに関する,太陽進化論・太陽系起源論・惑星形成論を背景にした様々な議論の整理 惑星大気観測: 探査とその推進戦略: 探査機・地球軌道上・地上からなどの観測技術に加え,他の地球惑星科学諸分野の進展状況,さらに国内外の技術的革新,経済的制約,社会的許容度などの調査・検討 生命の起源: 生命の起源に関する現状での理解と問題点,生命探査を含んだ惑星探査計画について調査・検討 8月27,28日に東京大学で約60名による「調査報告研究会」,9月24,25日に京都大学で約50名による「調査報告研究会」,3月6,7日に北海道大学で90名による「調査・検討と総合会議を開催した.検討結果は,今後の研究推進の指針ともなるべきものであり,「報告書」としてとりまとめる.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B), Grant-in-Aid for Scientific Research (B), University of Tokyo, 1997 - 1999Application of Wavelets to Observational Data AnalysisApplication of wavelet analysis to observational data is studied. Taking an acceleration data of earthquake as an example, we propose a data correction method consisting of biorthogonal wavelet expansion and Lagrange multiplier method. This method is based on wavelet expansion and enables us to correct the data locally in time-frequency domain. Moreover we devised an algorithm to generate biorthogonal wavelets which diagonalize/semi-diagonalize a class of linear operators in-variant to scale transformation, in order to reduce numerical task in the data correction including, integration, for example. We applied this algorithm to Riesz potential, derivative Hilbert transformation and Abel transformation. Numerical inspection shows that elements of the representation matrices decay rapidly in the off-diagonal region. This means that the matrices can accually be treated as band-diagonal ones, and permits us fast calculation. We also studied engineering application of wavelets to problems including friction and oscillation absorption.
- 日本学術振興会, 科学研究費助成事業 重点領域研究, 重点領域研究, 九州大学, 1996 - 1996地球内部流体運動基礎過程の研究〜ベナ-ル対流vs凝結性対流本研究は,マントル・中心核の対流への凝結性成分の存在が与える効果の基本的な性質を明らかにするために,その力学的構造をベナ-ル対流および熱フラックスを固定した対流理論の延長上で多成分多相系の対流を議論し,理解することを目指した. 竹広と林は,凝結性成分を含んだ対流を考察する際の比較対象となる標準実験と理論的考察を行なった.マントルの熱的な性質を考慮するために,温度固定熱境界条件を熱フラックス固定境界条件に変えた場合の回転系の対流の振舞を理論的に考察した。その結果,対流の水平スケールに与える回転の効果が回転軸の向きによって異なることがわかった.回転軸が鉛直方向を向いている系では水平方向に横長の対流セルの出現が抑制されるが,回転軸が水平方向を向いている境界面の傾いた系では水平方向に横長の対流セルが出現する.既存のブシネスク対流モデルに回転の効果を組み込み,数値計算を行なった結果,理論的な考察から予想されるものと整合的な結果が得られた. 一方,中島は地球流体核内の状況を想定して,大気の積雲対流モデルの相変化過程のパラメターを大きく変化させて下降流域で凝結過程が生じるようにモデルを改造し,凝結性成分(鉄)の落下速度を変化させて数値実験を行なった.数値計算の結果,凝結性成分(鉄)の落下速度が遅い場合では非定常な横長の対流セルが出現するのに対して,凝結性成分の落下速度が速い場合には定常でそれほど横長でない対流セルとなることがわかった.凝結性成分の落下速度の変化は,非凝縮性対流での熱的条件に対応させると凝結性成分の落下速度が遅い場合は内部熱源を伴わない対流問題,凝結性成分の落下速度が速い場合は内部熱源を伴う対流問題に相当する.このような熱的条件の差異によって,対流の水平スケールの変化を理解することが今後の課題である.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), University of Tokyo, 1995 - 1996The role of Rossby waves in decaying turbulent motion on a rotating sphere : an insight on zonal wind distributions of planetary atmospheres.The purpose of this study was to investigate the behavior oftwo-dimensional non-divergent flow on a rotating spherical shell. We expected to obtain some insight on the distribution of zonal flowsobserved in the real earth and/or planetary atmospheres. Our purpose also contained, in the mean time, developing a suitable computation and/or information environment for pursuing our scientific object. The experiment of developing common software resources and environment between the groups of University Tokyo and Kyushu University via Internet revealed several fatal issues to be improved in our program structures. There were heavy overhead problems in our developed software resources. The activity aiming at developing a structured software including high dimensional models, that is, the shallow water model and three dimensional spherical convection model, finished with not very satisfying stage. However, the collaboration experiment via Internet was carried out with good performance, partly owing to the eatablishment of SINET.The computer communication between the workstations of Tokyo and Kyushu presented good environment for destant collaboration. The two-dimensional spherical experiment with numerical method verified that the scenario in which Rossby waves are absorbed in the higher latitudes and deposit eastward angular momentum there was acceptable. The weak non-linear experiments in which the non-linear terms were restricted only to the zonal acceleration due to weak interaction confirmed that the acceleration mechanism was that described by weak non-linear theory. However, we couold not produce very convincing example where a wave packet was absorbed by the critical latitude as was expected by WKB theory. The resolution used in the experiment seemed to be insufficient in obtaining such results. The three dimentional spherical experiments showed that the equatorial zonal acceleration obtained by thermal convection is also explained by the dynamics of Rossby waves which emerge from the two dimensional constraint forced by the spherical geometry. We succeeded in classifying the east-west acceleration due to convective motion by the use of Rossby waves existing there.
- 日本学術振興会, 科学研究費助成事業 一般研究(C), 一般研究(C), 北海道大学, 1994 - 1994地球大気モデル用流体コードの地球型惑星大気パラメタへの拡張と基礎実験本研究の目的は,地球型惑星の大気循環の計算可能性を探ることにあった.目標は,太陽放射量の違いによる暴走温室状態の発生を循環場の構造まで含めて計算することであった. 水蒸気を赤外放射に対して灰色とみなす簡略な放射コードを導入し,太陽放射量を1350W/m^2〜1800W/m^2のあいだのいくつかの値に設定して,放射対流(平衡)状態を計算することを行なった.鉛直層数を16にした通常の場合には計算は発散することもなく,特に1次元放射対流平衡モデルで予想される限界射出量を越えた1800W/m^2では系から射出される外向き放射量が時間とともに減少する暴走温室状態と見られる状況が得られた. 鉛直層数16のモデルでは実は太陽定数が1350W/m^2程度の時の対流圏が再現できる分解能でしかない。1800W/m^2での結果をより確かなものにするために分解能を32にして再度計算を試みた.この層数は,1次元放射対流平衡モデルを用いた赤外放射計算がおおむね正しく行なえる最低限の数を調べ,導入したものである. 残念ながら,現時点では分解能32のモデルの計算には成功していない.長時間積分ができないでいるためである.原因は成層圏に伝搬する内部重力波の活動が数値コードの能力を上回っているためと想像している.興味深いことに赤道域上層は必ずスーパーロ-テーション状態となる.問題の解決に向けてより簡略な2次元対流実験の再試行を行なった.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for General Scientific Research (C), Grant-in-Aid for General Scientific Research (C), University of Tokyo, 1993 - 1994Study of high-dimensional attractors with scaling propertiesStatistical properties of a high-dimensional strange attractor with scaling properties is studied numerically. We adopted the shell model which was proposed by us to study fluid turbulence. This model was confirmed to have the Kolmogorov scaling properties in its chaotic state. When the Lyapunov dimention of the attractor is around 50, the probability distribution function (pdf) of a velocity variable becomes apart from Gaussian form as the wavenumber increases in the inertial range. In the dissipation range, the form of the pdf is found to deviate from a stretched exponential form and converges asymptotically to P (x) -|x|^<-1.6>. We compared this result with that of Navier-Stokes turbulence obtained from a direct numerical simulation of the equation. In order to interpret the result for the shell model, we employed the orthonormal wavelet analysis to construct the pdf of spatial distribution of Fourier components. This procedure shows that the functional form of the pdf for the Navier-Stokes turbulence also shows the convergence to the same power form in the deep dissipation range. This suggests that the pdf is, at least in the first approximation, determined only by basic properties of the equation. We also applied the wavelet method to observational data of atmospheric turbulence to see its usefulness.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for General Scientific Research (B), Grant-in-Aid for General Scientific Research (B), The University of Tokyo, 1992 - 1993Study of cloud and climate modification caused by global scale air pollution(1) NOAA/AVHRR LAC data sets were purchased and analyzed for retrieving cloud and aerosol microphysical parameters. We have developed an algorithm for getting cloud optical thickness and effective particle radius by making use of AVHRR channel 1,3 and 4 radiances. We also developed an algorithm for retrieving aerosol optical characteristics from AVHRR channel 1 and 2 and GMS band 1. (2) We have found examples of cloud modifications over areas such as the western coastal region of the North American Continent, the Amazon area, the Yellow Sea area, and the western coastal region of the African Continent. General characteristics for the modifications are that the clouds in the continental air mass have large liquid water path and small effective particle radius ; the clouds in the maritime air mass have small liquid water path and large effective particle radius. (3) The effect of the obtained cloud modification on climate has been estimated by a simple energy budget model. We found a cloud system which has drizzle particles can cool the climate system effectively. (4) We have developed an accurate yet efficient radiation code which can treat scattering/absorption/emission processes by clouds and aerosols as well as absorption/emission by gaseous constituents. This code has been successfully implemented into our numerical climate model. (5) In order to improve our description and prediction ability of radiative convective equilibrium states, the thermal convection theory of Boussinesq fluid is reconsidered aiming at constructing a basic theory for radiative convection which should replace the current theory basically developed for Benard convection. The focus is placed on examine the difference in the appearance of circulation structures caused by thermal conditions imposed to the system. Numerical calculations of two dimensional fluid show that the wavenumber one circulation structure and asymmetry of upward and downward motions, which are the characteristics considered generic to the moist convection, widely appear in the convection driven by internal cooling in general. Those features are also recognized in the calculations of three dimensional spherical convection.
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for international Scientific Research, Grant-in-Aid for international Scientific Research, University of Tokyo, 1991 - 1993International Cooperative Research on Climate VariationClimate changes of both natural and anthropogenic origins are now important issues not only in scientific community but in public because of their great(potential)impacts on human life and industry. For this reason an international cooperative research program "World Climate Research Program(WCRP)" is now going on. Japanese climate science community has been participating in this international endeavor through individual projects carried out by group of scientists organized by the sponsorship of Japanese funding agencies. In order to conduct these national research projects in a coherent manner with international ones it is necessary for representative scientists to communicate with international groups by participating in Working Groups and Science Steering Groups of the WCRP. The present project is organized to keep such an interface between Japanese and international groups.
- 日本学術振興会, 科学研究費助成事業 奨励研究(A), 奨励研究(A), 東京大学, 1991 - 1991放射対流平衡として得られる大気の軸対称循環に関する基礎的考察
- 日本学術振興会, 科学研究費助成事業 奨励研究(A), 奨励研究(A), 東京大学, 1990 - 1990熱流束を与えられた場合の対流運動についての基礎的考察
- 日本学術振興会, 科学研究費助成事業 一般研究(A), 一般研究(A), 東京大学, 1989 - 1990気候ダイナミックスの建設(1)ー地表面状態に応ずる大気大循環の形態の研究昨年度にひきつづき、大陸と海洋が東西に並んでいる場合の大気大循環の形態を、特に降水域のパタ-ンに着目して調べた。昨年度より水平分解能の高いT42スペクトル・モデルを用い、海洋をはさんだ東西両側の大陸の地面の湿潤度を変えて数値実験を実行し、次の結果を得た。 1.大陸の湿潤度にかかわりなく、海洋上西側では赤道をはさんで2本の降水帯を生じるが、東側では間隔が狭くなって1本にまとまり、U字形の降水域が生じる。これは海洋上で潜熱放出が大きい時の応答として理解できる。他方、大陸上では赤道沿いに1本の降水帯が作られた。これはケルビン波励起の結果と解釈できるが未検討である。 2.大陸の湿潤度を変えると、海岸近くの流れの場が敏感に変化する。すなわち、湿っている場合には、大陸から海洋に向かう流れができ、逆に乾いている場合には、海洋から大陸に吹き込むようになる。この結果から、西太平洋域に西風が入るのは、東南アジアの陸地が充分に湿っているためと解釈される。 上記の実験は、大気大循環モデルを用い、海面水温は固定して行ったものであるが、同様の実験を大気・海洋結合モデルを用いて海面水温をも計算する形で行った。その結果は、固定した場合と基本的に同じであった。 海洋深層循環のメカニズムを理解するため、長方形海洋を想定し、その南西端(実際の海洋では南極周辺海域)に冷源を置き、そこで形成される冷水が、どのように循環して海洋全体を満たすようになるかを数値実験した。その結果、古典的なストンメル・アロンのパタ-ンは常に出現するわけではなく、密度の水平拡散が充分に小さいときに限られることが示された。
- Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for international Scientific Research, Grant-in-Aid for international Scientific Research, University of Tokyo, 1989 - 1989Studies on gloval atmospheric waves and modeling of the general ciruculation of the atmosphere.Structure and variability of stratospheric planetary waves were analyzed by use of satellite data. It was found that in the southern hemisphere stratosphere wavenumber 2 component moves eastward unlike its northern hemispehre conuterpart. The component played an essential role in producing the strong sudden warming observed 1988 southern spring. A 2-dimensional photochemical/dynamical model of the atmospheric ozone was developed. Computed ozone distributions on the meridional plane are in good agreement with the observations.
- 日本学術振興会, 科学研究費助成事業 奨励研究(A), 奨励研究(A), 東京大学, 1989 - 1989波動伝幡理論によるシアー不安定メカニズムの研究
- 日本学術振興会, 科学研究費助成事業 一般研究(C), 一般研究(C), 東京大学, 1987 - 1988大気・地表面系のダイナミックスに関する基礎的研究地球上の機構とその変化を決定する要因として、海水面温度、陸上の雪氷、陸地面の湿潤度などがある。近年、気候変動メカニズムの解明が世界的に重要課題になるにつれ、大気とこれらの要因との関係を調べる研究が盛んに行われ始めた。本研究では、陸地面の湿潤度がその上の大気の状態や大気の流れに及ぼす影響を基礎的な立場から明らかにすることを目指す。 陸地面が大気に及ぼす効果を抽出するため、鉛直1次元モデルを作成した。大気の温度と水蒸気量は、放射・乱流拡散・凝結のプロセスによって決まる。土壌中では熱伝導のみを考える。土壌表面では、放射、顕熱・潜熱の大気との交換、地下への熱伝導のバランスによって温度が決まる。この研究の目的として、土壌水分量に応じて表面から大気への蒸発量が変化することを考慮し、陸地面の湿潤度を表すパラメーターβを導入した。β=1の場合が水面と同じであり、β=0は完全に水のない状態である。 β=1、0.1、0.01、のように湿潤度を変えた条件下で、モデルの時間積分を100日間行い、どのような大気状態が出現するか、蒸発量はどの程度変わるか、を調べた。時間積分にあたっては、太陽光の日変化をとり入れた。その結果次のことが明らかになった。(i)地面が湿っているほど地表面温度の日変化は小さい。(ii)地面が乾燥するにつれ、蒸発量は減少する傾向にあるが、その差はβの差に比べて著しく小さい。βが10分の1になっても蒸発量は2割ほど減少するに過ぎない。この原因について考察した。 以上の1次元モデルとともに、3次元の大気大循環モデルを用い、四角の海をとりまく大陸を仮定し、その陸地面のβを変えて実験を行い、1次元モデルと基本的に同じ結果を得た。
- 日本学術振興会, 科学研究費助成事業 一般研究(C), 一般研究(C), 東京大学, 1986 - 1987南半球夏季モンスーン(オーストラリアモンスーン)の年々変動の研究[±]オーストラリア・モンスーンの年々変動を季節内変動(30-60日周期振動との関連でとらえることを目的として, 1980-1984年の期間について, 南半球夏季の風の変動を調べた. 用いたデータは, ヨーロッパ中期予報センターで作られた格子点データで, 下層850mb面と上層20omb面の風の東西成分を, 村上によるディジタル・フィルターで, 周期で130日以上, 30-60日, 15日以下の3成分に分けてそれぞれの強度の変化を調べた. 南緯10°を中心とした領域で次の事が見出された. 1)850mb面で西風が早越しているときに, 東西成分の30-60日周期の振動の振幅が大きくなる. 2)西風の早越する領域は, およそ40°E-180°Eであるが, 年々による変動が大きい. すなわち, 1980/81年の12〜2月は, 100°E-160°W, 1981/82年の同時期には, 100°E-180°Eと40°E-80°Eの2個所, 1982/83年のエルニーニョの時期には, 120°E-140°Wと40°E-80°Eで東側の南西域は東太平洋に及び, 1983/84年の反エルニーニョの時期には, 40°E-160°Eと西太平洋西部に閉じこめられていた. [II]オーストラリア・モンスーンには, 同季節の北半球の冬季モンスーンによる寒気の低緯度域への溢れ出しが関係していることが, これまでの研究で示唆されて来た. そこで, 北半球の寒気の吹き出しが低緯度に及ぶメカニズムをさぐるため, チベット高原に沿う寒気の動きをデータ解析により調べた. その結果, 大陸上の寒気の吹き出し(コールド・サージ)には, 中国大陸全体にわたる大規模のものと, チベット高原の山腹沿いに局限されたケルビン波タイプのものの2種があること, 後者の方が動きが遠く, 大規模サージに先行することが明らかになった.
- 日本学術振興会, 科学研究費助成事業 自然災害特別研究, 自然災害特別研究, 東京大学, 1986 - 1986集中豪雨の予測可能性に関する数値実験この研究の当初目的は、対流雲の2次元数値モデルを用いて数値シミュレーションを行い、集中豪雨をもたらすような中小規模気象システムの予測可能性を検討することであった。ところが、昨年度までの研究によって完成したつもりの対流雲モデルに、いくつかの欠点のあることがわかり、このまゝで実験を行っても所期の目的を達成し得るような実験を行い得るとは限らないことがわかり、計画を変更して今年度はモデルの改良に力を注ぐことにした。問題と、それについての研究実施経過は次の通りである。 (1)原モデルでは、雲水量・雨水量の移流を計算するのに、2次の中央差分式を用いていた。この方式は、簡単で計算効率はよいのだが、差分式としての精度は余り良くない。これまでの結果を詳細に検討したところ、差分誤差のため、マイナスの雨が形成されることがあることがわかった。これは許容できない誤差なので、差分式をより良いものにする検討を行った。計算量の制約を考慮に入れて、種々の方式を検討し、実際にプログラムに組み入れてチェックを行った。その結果4次の差分式で保存則をみたす方式が適当であるとわかった。 (2)原モデルでは、雲物理過程として氷晶を含まない「暖かい雨」の過程のみを取り扱っていた。このモデルでも集中豪雨の原因となる対流雲の組織化は一応再現されていた。しかし詳しい検討の結果、本当は上層の絹雲(氷晶雲)のかなとこ状のひろがり(アンビル)によって広域に降水がもたらされ、近接する対流雲セルの振舞いに影響を与える点が重要であり、この過程を含まいモデルでは現実の雲のモデルとして不十分であることがわかった。そこで、氷晶、雪片、あられという3種の固体降水要素を新たに変数とし、その間の変換を含む雲物理過程のスキームを新たに開発しモデルに取り入れた。
- 日本学術振興会, 科学研究費助成事業 総合研究(B), 総合研究(B), 東京大学, 1986 - 1986モデルによる気象・気候研究の将来計画気候変動国際協同研究計画(WCRP)の日本における実施案がまとまり昭和62年度から開始されることになった。この研究計画においては、気象・気候の数値モデルによるコンピューター実験が中心的役割をはたす。気象・気候の数値モデルには莫大な計算を要し、このため、コンピューターの能力が劣っていた日本においては、この方面の研究は大幅に立遅れていた。最近に至ってコンピューター事情の好転に伴って、数値モデルによる研究がようやく日本でも可能となり、世界のレベルに追いつきつゝある。このような状況下において、既に蓄積のある世界の研究者から最近の成果や問題についての情報を得ることは、日本での研究を加速するのに必要かつ有効である。 折よく、昭和61年8月初旬に東京で短期・中期の数値天気予報に関する国際シンポジウムが開催され、数値モデルによる研究を行っている研究者多数が日本を訪れた。そこでこの機会を利用し、特に12名の第一線研究者を選んで早めに来日してもらい、日本の研究者とともに研究会を開いた。その概要は次の通りである。期日:昭和61年7月30日-8月2日。場所:京都市・京大会館。参加者:国外12名(米,英,スイス,中国,韓国)、国内約40名。発表論文数:50。 研究会では、東京でのシンポジウムでは聞けないような、数値モデルについての詳細なノウハウや、現在進行中の研究についての中間結果などを話してもらい、一方、日本側研究者もそれぞれの研究成果や経過を発表して討論を行い、今後の研究推進に有用な情報を得ることができた。したがって、この研究会を開いたことによって、日本のWCRPにおける数値モデル研究グループの研究実施計画は一段と向上し、世界のトップレベルに近づいたものと思われる。