Three-Dimensional Characteristics of Atmospheric Gravity Waves Using Advanced Balloon and Radar Observations in the Antarctic Region

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H01160
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 17020:Atmospheric and hydrospheric sciences-related
• Research Institution: National Institute of Polar Research
• Principal Investigator: Tomikawa Yoshihiro 国立極地研究所, 先端研究推進系, 准教授 (20435499)
• Co-Investigator(Kenkyū-buntansha): 齋藤 芳隆 国立研究開発法人宇宙航空研究開発機構, 宇宙科学研究所, 准教授 (50300702) ; 佐藤 薫 東京大学, 大学院理学系研究科(理学部), 教授 (90251496)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 大気重力波 / スーパープレッシャー気球 / 大型大気レーダー / 南極

Outline of Final Research Achievements

In order to capture the horizontal distribution of momentum transport by atmospheric gravity waves in the Antarctic region, we established a gravity wave observation program (LODEWAVE) using super-pressure (SP) balloons and conducted two campaigns. A total of five SP balloons were successfully launched, but the level flights in the lower stratosphere were all limited to three days or less. An analysis of simultaneous observation data with the PANSY radar showed that they captured the same near-inertial frequency gravity wave packets. Comparison with the latest atmospheric reanalysis data revealed that the gravity wave packets, which were qualitatively represented in the reanalysis data, may no longer be represented explicitly due to the shortening of vertical wavelengths as they propagated into regions of high static stability.

Free Research Field

中層大気科学

Academic Significance and Societal Importance of the Research Achievements

成層圏を長期間飛翔可能なSP気球は、科学観測や通信網構築の新たなプラットフォームとして米仏を中心に開発が進んでいるものの、日本では実現していなかった。本研究では、SP気球による科学観測に日本で初めて成功し、今後のSP気球の開発・普及への足掛かりとなると期待される。また、気候モデルの主要な不確定要素の1つである重力波による運動量輸送を、SP気球と大型大気レーダーで同時に捉える試みは本研究が世界初であり、今後の観測データの蓄積により、重力波研究の進展と気候変動予測の精度向上に貢献できると考えている。