• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

High vertical resolution observation of planetary atmospheres by radio occultation

Research Project

Project/Area Number 20H01958
Research Category

Grant-in-Aid for Scientific Research (B)

Allocation TypeSingle-year Grants
Section一般
Review Section Basic Section 17010:Space and planetary sciences-related
Research InstitutionThe University of Tokyo

Principal Investigator

Imamura Takeshi  東京大学, 大学院新領域創成科学研究科, 教授 (40311170)

Co-Investigator(Kenkyū-buntansha) 安藤 紘基  京都産業大学, 理学部, 准教授 (00706335)
野口 克行  奈良女子大学, 自然科学系, 准教授 (20397839)
神山 徹  国立研究開発法人産業技術総合研究所, 情報・人間工学領域, 研究チーム長 (40645876)
小郷原 一智  京都産業大学, 理学部, 准教授 (50644853)
杉山 耕一朗  松江工業高等専門学校, 情報工学科, 教授 (60463733)
Project Period (FY) 2020-04-01 – 2024-03-31
Project Status Completed (Fiscal Year 2023)
Budget Amount *help
¥17,550,000 (Direct Cost: ¥13,500,000、Indirect Cost: ¥4,050,000)
Fiscal Year 2023: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000)
Fiscal Year 2022: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000)
Fiscal Year 2021: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000)
Fiscal Year 2020: ¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000)
Keywords惑星大気 / 金星 / 火星 / 電波掩蔽 / 画像解析 / 数値シミュレーション / 大気重力波 / 電波掩蔽観測 / メソスケール気象 / メソ気象 / 大気 / メソスケール / 数値モデル / 対流 / 重力波
Outline of Research at the Start

電波ホログラフィを火星と金星の1000セットを超える電波掩蔽データに適用する。従来の手法ではとらえられなかった微細構造、たとえば対流プルームが安定層を押し上げる不連続面、地表近くの超安定層、短鉛直波長の重力波、その砕波が作る極薄の乱流層などの分布を明らかにする。また発生条件を明らかにするため光学観測データを用いて背景場を把握する。幅広いパラメータ条件で数値実験を行うことにより、大気密度が大きく異なる火星と金星の違いや、様々な高度で生じる対流層の違いを調べる。

Outline of Final Research Achievements

To understand mesoscale meteorology in planetary atmospheres, we obtained temperature data with high vertical resolution through radio holography using radio occultation data from Venus and Mars probes. We determined the global distribution of atmospheric gravity waves and estimated the excitation sources and decay processes of these waves. By analyzing cloud motions, we elucidated the mechanism behind the formation of the unique temperature structure observed in the polar regions of Venus. We advanced the understanding of mesoscale meteorology from the morphology and regional/seasonal variations of clouds on Mars. We developed a computation module for irregular grids using a coordinate system along the terrain applicable to steep planetary terrains. Building upon these achievements, we delved into discussions on the similarities and differences in mesoscale meteorology between Venus and Mars, and organized the directions for future observations and theoretical studies.

Academic Significance and Societal Importance of the Research Achievements

地球を含む惑星の気候・環境形成において惑星スケールからメソスケールまでの幅広い階層間の力学的相互作用が重要である。そのため地球大気科学では観測と数値モデルの高分解能化が進み、とくに境界層や内部重力波を含むメソスケール過程の研究が加速しているが、惑星大気の研究は大きく遅れている。本研究は、電波ホログラフィによる電波掩蔽データ解析や、惑星大気の高解像度画像の機械学習を応用した先進的解析などの観測的アプローチと、他惑星の極端な条件にも適用できる数値シミュレーション技術の開発を進め、地球・金星・火星のメソスケール気象の統一的解釈に踏み出した点が、世界的にもユニークな試みである。

Report

(5 results)
  • 2023 Annual Research Report   Final Research Report ( PDF )
  • 2022 Annual Research Report
  • 2021 Annual Research Report
  • 2020 Annual Research Report
  • Research Products

    (44 results)

All 2024 2023 2022 2021 2020 Other

All Int'l Joint Research (6 results) Journal Article (22 results) (of which Int'l Joint Research: 12 results,  Peer Reviewed: 22 results,  Open Access: 17 results) Presentation (16 results) (of which Int'l Joint Research: 9 results,  Invited: 1 results)

  • [Int'l Joint Research] ケルン大学(ドイツ)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research] Indian Space Research Organisation(インド)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research] NASA(米国)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research] Institute for Basic Science(韓国)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research] 気象力学研究所(LMD)(フランス)

    • Related Report
      2023 Annual Research Report
  • [Int'l Joint Research]

    • Related Report
      2023 Annual Research Report
  • [Journal Article] Long‐Term Variability of Mean Winds and Planetary‐Scale Waves Around Venusian Cloud Top Observed With Akatsuki/UVI2024

    • Author(s)
      Horinouchi Takeshi、Kouyama Toru、Imai Masataka、Murakami Shin‐ya、Lee Yeon Joo、Yamazaki Atsushi、Yamada Manabu、Watanabe Shigeto、Imamura Takeshi、Peralta Javier、Satoh Takehiko
    • Journal Title

      Journal of Geophysical Research: Planets

      Volume: 129 Issue: 3

    • DOI

      10.1029/2023je008221

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Gravity Wave Modulations at the Lower Altitudes of Venus Ionosphere2023

    • Author(s)
      TRIPATHI Keshav R.、CHOUDHARY R. K.、JOSE Jeslin S.、AMBILI K. M.、IMAMURA T.
    • Journal Title

      Geophysical Research Letters

      Volume: 50 Issue: 4

    • DOI

      10.1029/2022gl101793

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Venusian Ionosphere During Deep Solar Minima: Some New Insights Using Akatsuki Radio Science Experiment2023

    • Author(s)
      Tripathi Keshav R.、Choudhary R. K.、Ambili K. M.、Imamura T.
    • Journal Title

      Journal of Geophysical Research: Planets

      Volume: 128 Issue: 4

    • DOI

      10.1029/2023je007768

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Int'l Joint Research
  • [Journal Article] Venus cloud discontinuity in 20222023

    • Author(s)
      PERALTA J.、CIDADAO A.、MORRONE L.、FOSTER C.、BULLOCK M.、YOUNG E. F.、GARATE-LOPEZ I.、SANCHEZ-LAVEGA A.、HORINOUCHI T.、IMAMURA T.、KARDASIS E.、YAMAZAKI A.、WATANABE S.
    • Journal Title

      Astronomy & Astrophysics

      Volume: 672 Pages: L2-L2

    • DOI

      10.1051/0004-6361/202244822

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Cold Collar Reproduced by a Venus GCM With the Akatsuki Horizontal Wind Assimilation2023

    • Author(s)
      Ando Hiroki、Fujisawa Yukiko、Sugimoto Norihiko、Takagi Masahiro、Matsuda Yoshihisa
    • Journal Title

      Journal of Geophysical Research: Planets

      Volume: 128 Issue: 4

    • DOI

      10.1029/2022je007689

    • Related Report
      2023 Annual Research Report 2022 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Dependency of the vertical propagation of mountain waves on the zonal wind and the static stability in the lower Venusian atmosphere2023

    • Author(s)
      Suzuki Anna、Ando Hiroki、Takagi Masahiro、Maejima Yasumitsu、Sugimoto Norihiko、Matsuda Yoshihisa
    • Journal Title

      Icarus

      Volume: 402 Pages: 115615-115615

    • DOI

      10.1016/j.icarus.2023.115615

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Formation and Quasi‐Periodic Variation of Equatorial Jet Caused by Planetary‐Scale Waves in the Venusian Lower Cloud Layer2023

    • Author(s)
      Takagi Masahiro、Ando Hiroki、Imai Masataka、Sugimoto Norihiko、Matsuda Yoshihisa
    • Journal Title

      Journal of Geophysical Research: Planets

      Volume: 128 Issue: 11

    • DOI

      10.1029/2023je007922

    • Related Report
      2023 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] In-orbit recalibration of Longwave Infrared Camera onboard Akatsuki2023

    • Author(s)
      Taguchi Makoto、Kouyama Toru、Sugawa Temma、Murakami Shin-ya、Futaguchi Masahiko
    • Journal Title

      Earth, Planets and Space

      Volume: 75 Issue: 1 Pages: 53-53

    • DOI

      10.1186/s40623-023-01803-w

    • Related Report
      2023 Annual Research Report 2022 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] Cloud trains associated with Martian Mountain Lee Waves on the eastern side of the Phlegra Montes2023

    • Author(s)
      Ogohara Kazunori、Ro Maaya
    • Journal Title

      Earth, Planets and Space

      Volume: 75 Issue: 1

    • DOI

      10.1186/s40623-023-01767-x

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] Correlation of Venusian Mesoscale Cloud Morphology Between Images Acquired at Various Wavelengths2022

    • Author(s)
      Narita M.、Imamura T.、Lee Y. J.、Watanabe S.、Yamazaki A.、Satoh T.、Taguchi M.、Sato T. M.、Fukuhara T.、Yamada M.、Kouyama T.、Iwagami N.
    • Journal Title

      Journal of Geophysical Research: Planets

      Volume: 127 Issue: 6

    • DOI

      10.1029/2022je007228

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] The Mars system revealed by the Martian Moons eXploration mission2022

    • Author(s)
      Ogohara Kazunori、Nakagawa Hiromu、Aoki Shohei et al.
    • Journal Title

      Earth, Planets and Space

      Volume: 74 Issue: 1 Pages: 1-1

    • DOI

      10.1186/s40623-021-01417-0

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Dynamical Effect on Static Stability of the Venus Atmosphere Simulated Using a General Circulation Model: A Comparison With Radio Occultation Measurements2022

    • Author(s)
      Hiroki Ando, Koutarou Takaya, Masahiro Takagi, Norihiko Sugimoto, Takeshi Imamura, Hideo Sagawa, Silvia Tellmann, Martin Patzold, Yoshihisa Matsuda, Bernd Hausler, Sanjay Limaye, Raj Kumar Choudhary, Maria Antonita
    • Journal Title

      J. Geophys. Res. Planets

      Volume: 127 Issue: 3 Pages: 1-10

    • DOI

      10.1029/2021je006957

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Horizontal structures of bow-shaped mountain wave trains seen in thermal infrared images of Venusian clouds taken by Akatsuki LIR2022

    • Author(s)
      Kiichi Fukuya, Takeshi Imamura, Makoto Taguchi, Toru Kouyama
    • Journal Title

      Icarus

      Volume: 378 Pages: 114936-114936

    • DOI

      10.1016/j.icarus.2022.114936

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] Automated segmentation of textured dust storms on mars remote sensing images using an encoder-decoder type convolutional neural network2022

    • Author(s)
      Ogohara Kazunori、Gichu Ryusei
    • Journal Title

      Computers & Geosciences

      Volume: 160 Pages: 105043-105043

    • DOI

      10.1016/j.cageo.2022.105043

    • Related Report
      2022 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Unveiling of nightside cloud-top circulation of Venus atmosphere2021

    • Author(s)
      Kiichi Fukuya, Takeshi Imamura, Makoto Taguchi, Tetsuya Fukuhara, Toru Kouyama, Takeshi Horinouchi, Javier Peralta, Masahiko Futaguchi, Takeru Yamada, Takao M. Sato, Atsushi Yamazaki, Shin-ya Murakami, Takehiko Satoh, Masahiro Takagi, Masato Nakamura
    • Journal Title

      Nature

      Volume: 595 Issue: 7868 Pages: 511-515

    • DOI

      10.1038/s41586-021-03636-7

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Gravity Wave Packets in the Venusian Atmosphere Observed by Radio Occultation Experiments: Comparison With Saturation Theory2021

    • Author(s)
      Ryota Mori, Takeshi Imamura, Hiroki Ando, Bernd Hausler, Martin Patzold, Silvia Tellmann
    • Journal Title

      J. Geophys. Res.: Planets

      Volume: 126 Issue: 9

    • DOI

      10.1029/2021je006912

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Planetary-Scale Waves Seen in Thermal Infrared Images of Venusian Cloud Top2021

    • Author(s)
      Naoya Kajiwara, Takeshi Imamura, Makoto Taguchi, Toru Kouyama
    • Journal Title

      J.Geophys.Res.:Planets

      Volume: 126 Issue: 12

    • DOI

      10.1029/2021je007047

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] Quasi-Periodic Variation of the Lower Equatorial Cloud Induced by Atmospheric Waves on Venus2021

    • Author(s)
      Ando Hiroki、Takagi Masahiro、Sagawa Hideo、Sugimoto Norihiko、Sekiguchi Miho、Matsuda Yoshihisa
    • Journal Title

      Journal of Geophysical Research: Planets

      Volume: 126 Issue: 6 Pages: 1-10

    • DOI

      10.1029/2020je006781

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed / Open Access
  • [Journal Article] 金星探査機「あかつき」のデータ検索閲覧システムの開発2021

    • Author(s)
      杉山 耕一朗 , 村社 光誠, 村上 真也
    • Journal Title

      宇宙科学情報解析論文誌

      Volume: JAXA-RR-20-010 Pages: 119-126

    • URL

      http://id.nii.ac.jp/1696/00047377/

    • Related Report
      2021 Annual Research Report
    • Peer Reviewed
  • [Journal Article] Superrotation in Planetary Atmospheres2020

    • Author(s)
      Imamura Takeshi、Mitchell Jonathan、Lebonnois Sebastien、Kaspi Yohai、Showman Adam P.、Korablev Oleg
    • Journal Title

      Space Science Reviews

      Volume: 216 Issue: 5 Pages: 87-87

    • DOI

      10.1007/s11214-020-00703-9

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Thermal structure of the Venusian atmosphere from the sub-cloud region to the mesosphere as observed by radio occultation2020

    • Author(s)
      Ando Hiroki、Imamura Takeshi、Tellmann Silvia、Patzold Martin、Hausler Bernd、Sugimoto Norihiko、Takagi Masahiro、Sagawa Hideo、Limaye Sanjay、Matsuda Yoshihisa、Choudhary Raj Kumar、Antonita Maria
    • Journal Title

      Scientific Reports

      Volume: 10 Issue: 1 Pages: 1-7

    • DOI

      10.1038/s41598-020-59278-8

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Journal Article] Brightness modulations of our nearest terrestrial planet Venus reveal atmospheric super-rotation rather than surface features2020

    • Author(s)
      Lee Y. J.、Garc?a Mu?oz A.、Imamura T.、Yamada M.、Satoh T.、Yamazaki A.、Watanabe S.
    • Journal Title

      Nature Communications

      Volume: 11 Issue: 1 Pages: 1-8

    • DOI

      10.1038/s41467-020-19385-6

    • Related Report
      2020 Annual Research Report
    • Peer Reviewed / Open Access / Int'l Joint Research
  • [Presentation] Local time dependence of Venusian cloud-top SO2 obtained from Akatsuki UV images2023

    • Author(s)
      Tatsuro Iwanaka, Takeshi Imamura, Shohei Aoki
    • Organizer
      JpGU 2023
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Role of a Kelvin wave in the formation of Venusian discontinuous lower clouds2023

    • Author(s)
      Takeshi Imamura
    • Organizer
      55th DPS Meeting with EPSC (San Antonio)
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Venusian atmospheric structure revealed by Venus Express and Akatsuki radio occultation measurements2023

    • Author(s)
      H. Ando, T. Imamura, K. Noguchi, S. Tellmann, M. Paetzold, B. Haeusler, S. Limaye, R. K. Choudhary and M. Antonita
    • Organizer
      EnVision Workshop
    • Related Report
      2023 Annual Research Report
    • Int'l Joint Research
  • [Presentation] 電波掩蔽法を用いた金星赤道域における熱潮汐波の鉛直構造に関する観測的研究2023

    • Author(s)
      安藤紘基、野口克行、今村剛、髙木征弘、杉本憲彦、松田佳久
    • Organizer
      SGEPSS第154回 総会・講演会
    • Related Report
      2023 Annual Research Report
  • [Presentation] あかつきとVenus Express電波掩蔽観測で見られた気温と硫酸蒸気混合比の長期変動について2023

    • Author(s)
      安藤紘基、野口克行、今村剛、佐川英夫
    • Organizer
      惑星圏研究会
    • Related Report
      2023 Annual Research Report
  • [Presentation] 火星北半球における波状雲 の波長の季節変化2023

    • Author(s)
      小郷原一智
    • Organizer
      日本気象学会2023年度秋季大会
    • Related Report
      2023 Annual Research Report
  • [Presentation] 火星北半球における風下山岳波に伴う波状雲の形成高度2023

    • Author(s)
      小郷原 一智, 樓 麻彩
    • Organizer
      日本地球惑星科学連合2023年大会
    • Related Report
      2023 Annual Research Report
  • [Presentation] LIRの長期観測から得られた金星雲上層での平均温度と熱潮汐波の変動2023

    • Author(s)
      神山徹
    • Organizer
      SGEPSS第154回 総会・講演会
    • Related Report
      2023 Annual Research Report
  • [Presentation] あかつき電波掩蔽観測による金星大気中の硫酸蒸気混合比の測定2023

    • Author(s)
      安藤紘基, 野口克行, 尾沼日奈子, 今村剛, 佐川英夫
    • Organizer
      惑星圏研究会2023
    • Related Report
      2022 Annual Research Report
  • [Presentation] Venusian atmospheric structures revealed by Akatsuki radio occultation measurements2023

    • Author(s)
      Ando, H., T. Imamura, K. Noguchi, S. Tellmann, M. Patzold, B. Hausler, K. R. Choudhary, M. Antonita
    • Organizer
      Venus Surface and Atmosphere Workshop
    • Related Report
      2022 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Temperature perturbations in the Venusian atmosphere observed by spacecrafts2023

    • Author(s)
      Katsuyuki Noguchi, Aika Hagino, Chihiro Idehara, Hiroki Ando, Takeshi Imamura
    • Organizer
      Workshop for Venus modelling and observations 2023
    • Related Report
      2022 Annual Research Report
    • Int'l Joint Research
  • [Presentation] 10 Venusian-year scale temperature variation at the cloud level of Venus revealed by long-term observation of Akatsuki/LIR2022

    • Author(s)
      Kouyama et al.
    • Organizer
      44th COSPAR Scientific Assembly
    • Related Report
      2022 Annual Research Report
    • Int'l Joint Research
  • [Presentation] Vertical structure of thermal tides in the Venus equatorial region revealed by Akatsuki radio occultation measurements2022

    • Author(s)
      Ando, H., K. Noguchi, T. Imamura, M. Takagi, N. Sugimoto, Y. Matsuda, S. Tellmann, M. Patzold, B. Hausler, S. Limaye, R. K. Choudhary, M. Antonita
    • Organizer
      AOGS2022
    • Related Report
      2022 Annual Research Report
    • Int'l Joint Research
  • [Presentation] 金星探査機あかつきによる電波掩蔽観 測で得られた気温擾乱に関する研究2022

    • Author(s)
      萩野藍霞、野口克行、安藤紘基、今村剛、杉本憲彦、藤澤由貴子、高木征弘
    • Organizer
      第152回地球電磁気・地球惑星圏学会総会・講演会
    • Related Report
      2022 Annual Research Report
  • [Presentation] Recent results on the Venusian atmosphere from the Akatsuki mission2021

    • Author(s)
      Takeshi Imamura
    • Organizer
      DPS 2021
    • Related Report
      2021 Annual Research Report
    • Int'l Joint Research / Invited
  • [Presentation] Results from the Akatsuki radio occultation on Venus2021

    • Author(s)
      Takeshi Imamura
    • Organizer
      Venus Science Conference 2021
    • Related Report
      2021 Annual Research Report
    • Int'l Joint Research

URL: 

Published: 2020-04-28   Modified: 2025-01-30  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi