湖南雨凇与大气环流和海温因子的相关分析

雨凇是冬季影响湖南的一种主要气象灾害。对湖南雨凇与大气环流特征量、海温异常的相关性进行了分析。结果表明：亚洲区极涡面积和东亚槽位置对中国湖南雨凇天气影响极为重要。当欧亚纬向环流为低指数时，有利于中国湖南雨凇的形成；当东大西洋欧洲区阻塞高压面积指数为低指数和乌拉尔山区阻塞高压面积指数为高指数时，湖南多雨凇天气发生。冬季西太平洋副热带高压面积偏大、强度偏强、西脊点偏西不利于中国湖南雨凇发展。拉尼娜事件结束年同时为厄尔尼诺开始年的年份湖南雨凇最为严重，厄尔尼诺事件起始年湖南雨凇强度最轻。

Correlation analysis between glaze and atmospheric circulation as well as sea surface temperature in Hu′nan province

Glaze is one of the major meteorological disasters in winter of Hu′nan province.The correlations between glaze and atmospheric circulation as well as sea surface temperature were analyzed in Hu′nan province.The results indicated that the polar vortex area over Asia and the location of East Asian trough play an important role to glaze weather in Hu′nan province.It is favorable to the formation of glaze in Hu′nan province when Eurasian zonal circulation index is low.Glaze weather often happens in Hu′nan province when the area index of East Atlantic blocking high over European is low and that of the Ural blocking anticyclone is high.It is not favorable to the development of galze in Hu′nan province if the area of western Pacific subtropical high becomes large and its intensity is strong,and the western normal position leans to west in winter.Glaze in Hu′nan province is most serious in the year that La Nina event ends and at the same time El Nino event begins.On the contrary,it is not serious in the starting year of El Nino event.