[A-CG47] 海洋と大気の波動・渦・循環の力学

[ACG47-P02] 大気中の波動によるエネルギー循環の見える化：中立波と不安定波の違い

*相木 秀則¹、菅野 湧貴²、原田 やよい³、小林 ちあき³、豊田 隆寛³、名倉 元樹⁴、尾形 友道⁴、野口 峻佑⁵、藤波 初木¹ (1.名古屋大学、2.電力中央研究所、3.気象研究所、4.海洋研究開発機構、5.九州大学)

This study addresses the challenge of bridging equatorial and quasi-geostrophic dynamics to diagnose group velocity vectors continuously across all latitudes. The theoretical advancements by Aiki, Greatbatch, and Claus (2017) and Aiki et al. (2021) resolved this issue, enabling seamless visualization of wave energy circulation patterns and advancing research into ocean wave phenomena linked to mechanisms such as the Indian Ocean Dipole Mode, the Atlantic Niño/Niña, and the El Niño-Southern Oscillation.The AGC diagnostic scheme is applied to an atmospheric reanalysis product in this study, focusing on the January monthly climatology for 1990–2009. The analysis shows that diabatic processes a drive and dissipate waves. Group velocity is directed downward in the lower troposphere, explained by the energy-wave-activity ratio, and eastward in the upper troposphere, attributed to unstable waves. In off-equatorial regions, the AGC energy flux and the quasigeostrophic energy flux are consistent in magnitude and structure.This is attributed to the finding that most atmospheric waves in the mid-latitude troposphere exhibit characteristics similar to unstable waves the Eady problem with the arbituraral vertical structure of basic flow.