对流层及平流层低层全球动能的季节性急变

On the Seasonal Transition in Global Kinetic Energy at 100hPa and 300hPa

利用１９８０—１９８８年ＥＣＭＷＦ的资料，分析对流层５００ｈＰａ、３００ｈＰａ和平流层低层１００ｈＰａ全球范围的纬向平均动能（ＫＺ）和涡动动能（ＫＥ）的季节过渡，比较不同层次不同纬度带动能模态的季节性急变，得到如下结论：（１）北半球热带与温带各层次的ＫＺ都有季节性急变，发生在３—４月和１０月附近，而南半球仅在热带有急变。（２）北半球热带地区ＫＺ在６月还有一次季节性急变，出现在１００ｈＰａ和５００ｈＰａ。（３）１００ｈＰａ动能的季节性急变要比３００ｈＰａ或５００ｈＰａ剧烈而又频繁。对各层而言ＫＺ的急变比ＫＥ显著。

tilizing the data of monthly mean of the zonal kinetic energy(KZ)and eddy kinetic energy(KE)over the entire globe at 500hPa, 300hPa and 100hPa during the period of 1980-1988,the seasonal rapid changes(SRC)in the general circulation in terms of these kinetic energy modes have been investigated.Three main results are obtained. First,seasonal rapid changes of KZ take place generally in March.April and October at the three levels over the northern extratropical and tropical belts,but in the south only in the tropic there exist rapid changes.Second,in June there are also seasonal rapid changes of KZ over the northern tropic at 100hPa and 500hPa,which are located at the lower stratosphere and midtroposphere,Third,rapid changes at 100hPa are often more obvious than that at 300hPa.And the seasonal changes for KZ at the three level,are more significant than that for KE.