近40a江苏省冬季气温异常的演变及其涨气背景场特征

通过1961－1998年江苏省11个站点冬季平均气温的EOF分析，探讨江苏省冬温异常的演变特征，并分析其同期及前期500hPa高度距均，海温距平场的特征，指出冬季异常冷年，同期与前期500mPa高度距平场主要表现为亚洲－太平洋地区阻塞形势发展，经向环流加强，同期至前期6个月赤道东太平洋海温为持续负距平。而暖冬同期与前期500hPa高度距平场的特征特征是，西太平洋海温为持续负距平。而暖冬同期与前期500hPa高度距平场的特征是，西太平洋副高势力较强，亚欧大陆中高纬 纬向环流占优势，同期赤道东太平洋海温具有厄尔尼诺的特征，但前期赤道东太平洋海温距平具有由负向正转变特征。

VARIATION OF 1961~1998 WINTER TEMPERATURE ANOMALY IN JIANGSU AND ITS AIR-SEA BACKGROUND FEATURES

Based on the EOF analysis of winter average temperature of eleven stations in Jiangsu Province from 1961 to 1998,the winter temperature anomaly variation feature is analysed,and further,the 500hPa height departure,SSTA in the same and preceding months are analysed.Results show that in cold winters,blocking grows in Asia Pacific region both in winter and in the preceding months with meridional currents enhanced,and SSTA being negative in eastern equatorial Pacific in the preceding 6 months.While the 500hPa height anomaly of warm winters bears the characteristics of strong western Pacific subtropical high, zonal flow prevailing in mid and high latitude in Asia Europe continent. The tropical eastern Pacific SST takes on the El Nino features,with SSTA in the preceding months transitting from negative to positive.