Linkage between winter sea surface temperature east of Australia and summer precipitation in the Yangtze River valley and a possible physical mechanism  

作　　者：ZHOU BoTao 

机构地区：[1]National Climate Center, China Meteorological Administration, Beijing 100081, China

出　　处：《Chinese Science Bulletin》2011年第17期1821-1827,共7页

基　　金：supported by the Special Fund for Public Welfare Industry (Meteorology) (GYHY200906018);the National Natural Science Founda- tion of China (40805029);the National Basic Research Program of China (2009CB421407 and 2010CB950304)

摘　　要：The relationship between winter sea surface temperature (SST) east of Australia and summer precipitation in the Yangtze River valley and a possibly related physical mechanism were investigated using observation data.It is found that winter SST east of Australia is correlated positively to summer precipitation in the Yangtze River valley.When the SST east of Australia becomes warmer in winter,the western Pacific subtropical high and the East Asian westerly jet tend to shift southward the following summer,concurrent with low-level southwesterly anomalies over eastern China.These conditions favor precipitation increase in the Yangtze River valley,whereas the opposite conditions favor precipitation decrease.The influence of winter SST east of Australia on East Asian summer atmospheric circulations may occur in two ways.First,by an anomalous SST signal east of Australia in winter that persists through the following summer,thus affecting East Asian atmospheric circulations via the inter-hemispheric teleconnection.Second,when the SST east of Australia is warmer in winter,higher SST appears simultaneously in the southwest Indian Ocean and subsequently develops eastward by local air-sea interaction.As a result,the SST in the Maritime Continent increases in summer,which may lead to an anomalous change in East Asian summer atmospheric circulations through its impact on convection.The relationship between winter sea surface temperature （SST） east of Australia and summer precipitation in the Yangtze River valley and a possibly related physical mechanism were investigated using observation data. It is found that winter SST east of Australia is correlated positively to summer precipitation in the Yangtze River valley. When the SST east of Australia becomes wanner in winter, the western Pacific subtropical high and the East Asian westerly jet tend to shift southward the following sum- mer, concurrent with low-level southwesterly anomalies over eastern China. These conditions favor precipitation increase in the Yangtze River valley, whereas the opposite conditions favor precipitation decrease. The influence of winter SST east of Australia on East Asian summer atmospheric circulations may occur in two ways. First, by an anomalous SST signal east of Australia in winter that persists through the following summer, thus affecting East Asian atmospheric circulations via the inter-hemispheric teleconnection. Second, when the SST east of Australia is wanner in winter, higher SST appears simultaneously in the southwest Indian Ocean and subsequently develops eastward by local air-sea interaction. As a result, the SST in the Maritime Continent increases in summer, which may lead to an anomalous change in East Asian summer atmospheric circulations through its impact on convection.

关 键 词：夏季降水 澳大利亚 长江流域 物理机制 海面温度 冬季 东亚大气环流 西太平洋副热带高压 

分 类 号：P434[天文地球—大气科学及气象学]