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-CG43] [EE] 中緯度大気海洋相互作用

2017年5月20日(土) 10:45 〜 12:15 ポスター会場 (国際展示場 7ホール)

コンビーナ:西井 和晃(三重大学大学院生物資源学研究科)、佐々木 克徳(Hokkaido University)、杉本 周作(東北大学大学院理学研究科)、大石 俊(東京大学大学院理学系研究科地球惑星科学専攻)

[ACG43-P05] Influences of sea surface temperature on a heavy rainfall event over Shimane in late August 2013

★招待講演

*宮坂 貴文1中村 尚1石垣 理生2 (1.東京大学先端科学技術研究センター、2.東京大学理学部地球惑星環境学科)

キーワード:sea surface temperature, heavy rainfall, air-sea interaction, Tsushima current

Shimane in western Japan suffered from heavy rainfall in late August 2013. This heavy precipitation is associated with a seasonal rain front and warm humid airflow over the Tsushima warm current. Although sea surface temperature (SST) distribution is considered to be important for the heavy precipitation, SST analysis data sets with high spatial resolution currently available have certain uncertainties because of differences in observations used and analysis procedures for the datasets. To investigate influences of SST on the heavy precipitation event and its sensitivity to SST datasets, we have conducted hindcast experiments with the weather research and forecasting (WRF) model with 3-km horizontal resolution with five different SST data as its lower-boundary condition. The experiments can reproduce heavy precipitation, though somewhat underestimated. The experiments have confirmed that the experiments with warmer SST data along the Tsushima current tend to reproduce the stronger precipitation. Since differences in evaporation and near-surface equivalent potential temperature are sensitive to the SST distribution, moisture supply, low-level stability and resulted precipitation can be modified by uncertainties in SST estimations. Therefore, the present study implies that quantitatively more accurate forecasts of heavy precipitations require more reliable SST distribution.