南亚季风区加热影响副高的数值试验

NUMERICAL EXPERIMENTS OF THE WEST-PACIFIC SUBTROPICAL HIGH INFLUENCED BY HEATING IN SOUTH-ASIAN MONSOON AREA

关键词:  南亚季风区加热  西太平洋副热带高压  数值试验

Key words:  Heating over South-Asia monsoon area Influence upon subtropical high over west Pacific Numerical experiment

摘要:

就一次出梅时西太平洋副热带高压的北进过程,从加热场角度用数值试验的方法研究了南亚季风区对副高活动的影响,并利用统计方法进行了显著性检验。结果表明;南亚季风区正的加热增强将激发出一支自最大加热中心向东北方向传播的波列,至第3天将在日本到华北建立一强正区平中心,从而有利副高增强。此外,还比较了南亚季风区加热与副高南侧热带辐会带加热对副高影响的差异。结果认为;南亚季风区正加热更有利于副高北进,而副高南侧热带辐合带正加热更有利于副高西伸;从影响副高的时间来看,南亚季风区正加热在第3天便使副高增强,而副高南侧热带辐合带正加热的作用偏晚,在第5天影响才明显起来。

Abstract:

For a case in which the subtropical high over the western pacific (SHWP) shifted to northwest and mei-yu at Yangtze River valley ended, several numerical experiments on SHWP activityinfluenced by heating in South-Asia monsoon area are carried out. The results indicate that the enhancement of positive heating in South-Asia will produce one wave train, which propagates northeastward from the maximum heating center, and one strong positive anomaly center will appearfrom Noth-China to Japan in the third day and it will result in the enhancement of SHWP. Thecomparison of influences upon SHWP between the heating in South-Asia monsoon area and thatin ITCZ area south to SHWP is also carried out. It was pointed out that the heating in South-Asiamonsoon area is in favor of SHWP movement to the north while the heating in ITCZ area is in favor of SHWP stretch to the west. So far as the reponse to the influence on SHWP is concerned,the heating over South-Asia monsoon area favors enhancement of SHWP after the third daywhile the heating over YTCZ south to SHWP but after the fifth day.