摘要
利用NCEP/NCAR月平均再分析格点资料,包括OLR资料、500hPa位势高度场等资料,借助相关分析、合成分析,研究了夏季热带对流的强弱对西太平洋副热带高压位置、强度变化以及江淮流域降水的影响。夏季从菲律宾周围经南海到中印半岛上空的对流活动增强或减弱时,西太平洋副热带高压位置偏北或偏南,且向北进时,在6月末和7月初存在明显或不明显突跳,从而影响东亚季风雨带在长江、淮河流域的停滞时间,造成长江流域和淮河流域降水偏少或偏多。
By NCEP/NCAR monthly mean reanalysis data including OLR,500 hPa geopotential height field and so on,effects of summer tropical convection on the location and intensity variation of Western Pacific subtropical high,rainfall of Yangtze valley and Huaihe River basin were studied by using correlation analysis,synthesis analysis.In summer,when the convective activities are intensified (weakened) from the areas around Philippines to Indo-China Peninsula through South China Sea,the Western Pacific subtropical high may shift northward (southward).What's more,the Western Pacific subtropical high has obvious abrupt shifts or unobvious abrupt shifts in the end of June and early July during its northward advance.It affected the stagnation time of East Asia monsoon rain-belt in the Yangtze valley and Huaihe River basin,and caused that the rainfall of this zone was below or above normal.
关键词
对流活动
副热带高压
OLR
Convective activity
Subtropical high
OLR
China
