日本地球惑星科学連合2018年大会

講演情報

[JJ] 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-AS07] 成層圏・対流圏過程とその気候への影響

2018年5月23日(水) 15:30 〜 17:00 ポスター会場 (幕張メッセ国際展示場 7ホール)

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

[AAS07-P03] 成層圏界面上昇イベントが下層大気循環に与える潜在的影響

★招待講演

*野口 峻佑1吉田 康平1出牛 真1黒田 友二1 (1.気象庁気象研究所)

キーワード:成層圏界面上昇イベント、高エネルギー粒子降り込み、成層圏突然昇温、化学気候モデル

The reformation of a separated elevated stratopause after strong stratospheric sudden warmings is an important phenomenon in the coupling between the stratosphere and mesosphere-lower thermosphere. Since such events, called as the Elevated Stratopause Events (ESEs), are closely linked to the downward transport of NOx produced in the mesosphere and thermosphere via the Energetic Particle Precipitation (EPP), they could contribute to catalytic ozone destruction in the stratosphere. This is a notable case of the so-called EPP indirect effect. Here, we analyze the polar stratospheric ozone loss due to ESEs and its impact on the lower atmospheric circulation in the Earth System Model of Meteorological Research Institute (MRI-ESM). By introducing the energetic particle forcing in the MRI-ESM, the EPP indirect effect is examined for multiple ESEs. In simulations which are nudged toward reanalysis data in the troposphere and stratosphere while being unconstrained above, ozone reduces by up to 40% in the upper stratosphere for several weeks after ESEs due to the NOx enhancements. The reduction of stratospheric ozone causes cooling anomalies of the polar-cap temperature and westerly anomalies of the zonal-mean zonal wind during the period of sunlit. Further, it is revealed that such anomalies can propagate down to the troposphere and surface by conducting a series of ensemble simulations, without the nudging, for a case of the largest ESE accompanied by large EPP. Thus, this study presents the possible coupling between the upper-to-middle atmosphere and lower atmosphere via the ESE.