青藏高原冬季雪盖增大对夏季东亚大气环流影响的数值试验

NUMERICAL SIMULATION OF THE IMPACT OF WINTER SNOW COVER AT QINGHAI XIZANG PLATEAU ON SUMMER GENERAL CIRCULATION OVER EAST ASIA

关键词:  青藏高原雪盖  东亚季风  西太平洋副高  数值试验

Key words:  Snow cover at Qinghai-Xizang Plateau  East Asia-monsoon  Subtropical high of Western Pacific ocean  Numerical simulation

摘要:

利用大气环流九层谱模式,即澳大利亚L9R 15A GCM,进行了青藏高原雪盖增大对夏季东亚大气环流及其季节变化影响的数值试验。试验结果表明,青藏高原冬季多雪,则导致西太平洋副高减弱东撤,南亚高压减弱南移,东亚季风减弱及季节变化异常。它还使西太平洋副高季节性北移稍提前,减低了北移所达的纬度,以及缩短了东亚夏季流型的持续时间。这些大多与过去的观测事实基本一致。

Abstract:

A 9-layer spectral general circulation model.i.e.,Australian L9R15 AGCM,was used to simulate the impacts of increasing winter snow cover at Qinghai-Xizang Plateau on summer general circulation over East Asia and its seasonal anormality.Preliminary results show that if winter snow cover on Qinghai-Xizang Plateau is larger than normal,the Subtropical high of western Pacific will be weakened and move eastward,Southern Asia high will also be weakened and move southward,meanwhile East Asia monsoon will be weakened and its seasonal variation is anormal.That means the beginning of seasonal northward moving of Subtropical high in western Pacific Ocean is earlier,the maximum latitude of northward moving is lower,and the maintenance duration of East Asia monsoon is shorter.These are almost the same as results in other papers.