[A-OS15] 海洋と大気の波動・渦・循環力学

[AOS15-03] 高解像度熱帯海洋ネストモデルを組み込んだ地球システムモデルによる気候シミュレーション

★招待講演

*今田 由紀子¹、山中 吾郎¹、辻野 博之¹、浦川 昇吾¹、高槻 靖¹ (1.気象庁気象研究所)

キーワード：熱帯不安定波、エルニーニョ・南方振動、地球システムモデル、高解像度熱帯海洋ネストモデル

Climatic impacts of mesoscale eddies in the tropical oceans on the oceanic mean states, atmospheric circulation, ENSO, and other natural variabilities are investigated using an earth system model MRI-ESM1 where a high-resolution tropical ocean model is nested. Because of the realistic representation of tropical instability waves (TIWs), the simulated eddy heat flux improves not only tropical oceanic mean states but also spatial distributions of mean surface wind stress and precipitation in the nested version of MRI-ESM1. ENSO characteristics (amplitude, period, spatial pattern, teleconnection) are also modified through the changes of mean state. Interestingly, nonlinear eddy heat transports due to TIWs increase the ENSO skewness and improve the characteristics of ENSO nonlinearity.