JpGU-AGU Joint Meeting 2017

講演情報

[EE] ポスター発表

セッション記号 A (大気水圏科学) » A-CG 大気水圏科学複合領域・一般

[A-CG45] [EE] 熱帯インド洋・太平洋におけるマルチスケール大気海洋相互作用

2017年5月20日(土) 15:30 〜 17:00 ポスター会場 (国際展示場 7ホール)

コンビーナ:名倉 元樹((独) 海洋研究開発機構)、H Annamalai(University of Hawaii at Manoa)、清木 亜矢子(海洋研究開発機構)、今田 由紀子(気象庁気象研究所)

[ACG45-P03] Intraseasonal coastal upwelling and heat balance in the mixed layer along the southeastern coasts of Sumatra and Java

*堀井 孝憲1植木 巌1安藤 健太郎1 (1.海洋研究開発機構 地球環境観測研究開発センター)

キーワード:Eastern Indian Ocean, Sumatra and Java, Coastal Upwelling, Mixed Layer, Surface Heat Flux

Coastal upwelling along the southwestern coasts of Sumatra and Java brings cool and nutrient-rich water to the coastal region, and plays an important role in the ocean surface heat and biogeochemical balance in the eastern Indian Ocean. In this study, to understand the coastal upwelling system, we investigated intraseasonal-scale thermodynamic balance in the mixed layer of the coastal region. We used satellite-based observational datasets of surface heat flux, SST, sea level, and ocean surface currents. Ocean mixed layer depth was estimated by Argo floats. During summer monsoon, intraseasonal-scale anomalous cold SST south of Java developed with anomalous southeasterly winds in the southeastern tropical Indian Ocean. The wind anomalies enhanced climatological southeasterly winds and hence latent heat loss. The anomalous latent heat loss was partly canceled by enhanced shortwave radiation, and the SST cooling could not fully explained by the net air-sea flux variations. Local sea level anomalies were lowering at this phase, suggesting that coastal upwelling played a role in the SST cooling. On the other hand, anomalous SST variations off of Sumatra were mainly controlled by anomalous surface heat flux variations. The implications of these results for regional and basin-scale air-sea interaction will be discussed.