7月南半球500hPa极涡异常的度量及其与极区增暖的联系  

Measurement of Southern Polar Vortex Anomaly at 500 hPa in July and Its Relationship with Global Warming

作　　者：卢楚翰[1,2] 管兆勇[1,2] 王盘兴[1,2] 秦育婧[1,2] 

机构地区：[1]南京信息工程大学气象灾害省部共建教育部重点实验室,江苏南京210044 [2]南京信息工程大学大气科学学院,江苏南京210044

出　　处：《大气科学学报》2010年第2期174-179,共6页Transactions of Atmospheric Sciences

基　　金：江苏省研究生培养创新项目(CX08B-017Z;E3000008098005);国家自然科学基金资助项目(40675025)

摘　　要：利用ECMWF月平均再分析资料,构造了500hPa7月南极极涡面积、强度指数。结果表明,定义的面积及强度指数为两个独立参数,通过分析南半球高纬度地区500hPa位势高度场EOF的主要模态以及典型年份的南极极涡差异,表明强度指数比面积指数更能代表极涡的强度变化。7月500hPa南极极涡强度指数与同期南半球高纬地表温度的变化趋势一致,下垫面的加热作用与南极极涡强度变化联系密切,在全球变暖背景下极涡面积收缩与热带扩张存在联系。Based on ECMWF ERA-40 reanalysis monthly mean dataset,area and the strength index of the southern polar vortex（PV） at 500 hPa in July was constructed.By studying the first EOF mode of southern polar region at 500 hPa geopotential height and the PV differences between 1979 and 1991,the result shows that the strength index and the area index are two independent parameters in describing PV while the strength index is more competent in describing variation of PV strength than the area index.The variation of PV strength is consistent with the surface temperature in southern high latitude region,and low levels＇ heating effect is essential for the strength variation of PV.The area index is significantly correlated with the expansion of traditional tropical belt.

关 键 词：南极极涡 强度指数 面积指数 气候增暖 

分 类 号：P434[天文地球—大气科学及气象学]