冬季平流层北极涛动对江南气温的影响  

Influences of Arctic Oscillation on surface air temperature over the south Yangtze River regions

作　　者：施宁[1,2] 张乐英[1] 

机构地区：[1]气象灾害教育部重点实验室(南京信息工程大学) [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》2013年第5期604-610,共7页Transactions of Atmospheric Sciences

基　　金：国家自然科学基金资助项目(41105042);国家科技支撑计划项目(2009BAC51B02);江苏省高校"青蓝工程"

摘　　要：利用ERA-interim及NCEP-DOE两种再分析资料,分析了冬季北极涛动(Arctic Oscillation,AO)与我国江南地区地表气温相关的时空结构。结果表明:1)2月30 hPa的AO指数与江南地区地表气温的同期相关系数最高,这与AO指数和江南地区地表气温的标准差均在2月极大有关。2)30 hPa的正AO事件加强时,贝加尔湖地区对流层易出现显著的正位势高度异常,有利于东亚地区出现向南、向下的异常风场,与之对应,西伯利亚高压向南扩展,有利于北方冷空气南侵至我国江南地区,造成局地气温负距平;反之亦然。Based on ERA-interim and NCEP-DOE reanalysis data, this paper studies the spatial-temporal relationship between the boreal wintertime Arctic Oscillation （AO） and the surface air temperature （SAT） over the south Yangtze River regions. Results show that： 1 ） The simultaneous correlation coeffi- cient is the largest between AO index at 30 hPa and SAT over the south Yangtze River regions in Feb- mary,in association with the fact that the standard deviations of both the AO index at 30 hPa and the SAT over the south Yangtze River regions achieve their maximum in February. 2 ）When the positive AO event is strengthened at 30 hPa, there are obvious positive geopotential height anomalies in tropo- sphere over the Baikal region, which is favorable for the anomalous southward and downward wind over East Asia. Accordingly, Siberian high tends to extend southward, which contributes to the occurrence of negative SAT anomalies over the south Yangtze River regions through the southward intrusion of north cold air, and vice versa.

关 键 词：平流层 北极涛动 江南气温 

分 类 号：P423[天文地球—大气科学及气象学]