Mechanism of zonal wind variation in Venus stratosphere

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K17767
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Meteorology/Physical oceanography/Hydrology
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Kouyama Toru 国立研究開発法人産業技術総合研究所, 人工知能研究センター, 研究員 (40645876)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 金星 / 惑星大気 / スーパーローテーション / 大気波動 / あかつき

Outline of Final Research Achievements

In this study, enhancement and propagation of planetary scale waves, which can accelerate and decelerate the super-rotation (fast zonal wind flow) in the Venus atmosphere, were investigated based on observation and simulation approaches. Based on observations of thermal emission from the Venus cloud top by a ground-based telescope and Akatsuki, which is a Japanese Venus climate orbiter, large stationary gravity waves were newly discovered and have been continuously observed. The stationary waves have been considered to propagate from the lower atmosphere. Since waves can propagate momentum transportation, this discovery provides newly perspective of connection between lower atmosphere and upper atmosphere through the momentum exchange by the waves.
In addition, it was found that Kelvin and Rossby waves shows different vertical propagating ways depending on variation of the background zonal wind speed, that indicates they provide different momentum transportation in Venus atmosphere.

Free Research Field

惑星気象学