日本地球惑星科学連合2019年大会

講演情報

[J] ポスター発表

セッション記号 A (大気水圏科学) » A-AS 大気科学・気象学・大気環境

[A-AS05] 成層圏・対流圏過程とその気候への影響

2019年5月29日(水) 15:30 〜 17:00 ポスター会場 (幕張メッセ国際展示場 8ホール)

コンビーナ:河谷 芳雄(国立研究開発法人海洋研究開発機構)、渡辺 真吾(国立研究開発法人海洋研究開発機構)、関谷 高志(国立研究開発法人 海洋研究開発機構)、佐藤 薫(東京大学 大学院理学系研究科 地球惑星科学専攻)

[AAS05-P01] An advanced impact of Arctic stratospheric ozone changes on spring precipitation in China

*Fei Xie1 (1.Beijing Normal University)

キーワード:Arctic Stratospheric Ozone, Spring precipitation

The effect of spring Arctic Stratospheric Ozone (ASO) changes on spring precipitation in China is analyzed using observations, reanalysis data, and the Whole Atmosphere Community Climate Model version 4 (WACCM4). We find that February–March mean ASO changes have a significant impact on April–May mean precipitation over the Loess Plateau and the middle–lower reaches of the Yangtze River—two important grain-producing regions with large populations. Changes in the polar vortex link the ASO to precipitation in China. Stratospheric circulation anomalies caused by ASO changes can propagate to the North Pacific. An increase in ASO leads to enhanced westerlies in the high and low latitudes of the North Pacific but weakened westerlies in the mid-latitudes of the North Pacific. The circulation anomalies over the North Pacific, forced by the increase of ASO, can extend westwards to East Asia, leading to an abnormal anticyclone in the East Asian upper and middle troposphere, and an abnormal cyclone in the lower troposphere. This enhances the warm and humid airstream from the Western Pacific to the Chinese mainland and strengthens upwelling over the Loess Plateau and the middle–lower reaches of the Yangtze River. These conditions enhance precipitation in central China during positive ASO anomaly events and reduce precipitation during negative events. The WACCM4 simulations support the results from our statistical analysis of observations and reanalysis data. Our results suggest that ASO variation can serve as a predictor of spring precipitation variation over the Loess Plateau and the middle–lower reaches of the Yangtze River.