湖南重大雨凇过程大气环流特征分析  

STUDY ON THE GENERAL CIRCULATION FOR SEVERE ICY RAIN EVENTS IN HU’NAN PROVINCE

作　　者：廖玉芳[1] 陈耀湘 吴贤云[1] 居晶琳[1] 

机构地区：[1]湖南省气候中心,湖南长沙410007 [2]湖南省气象服务中心,湖南长沙410007

出　　处：《热带气象学报》2013年第2期271-280,共10页Journal of Tropical Meteorology

基　　金：2009年中国气象局业务项目(全国气象灾害风险区划);湖南省科技计划重大专项(2008FJ1006)共同资助

摘　　要：利用NCEP 2.5°×2.5°再分析资料,对湖南省1951—2010年出现的8次重大雨凇过程进行大气环流特征、水汽特征及温度特征分析得出,8次重大雨凇过程有6次出现在阻高环流背景下,2次出现在纬向多波型环流背景下;雨凇范围及持续时间与阻高轴线向东北倾斜程度、阻高东侧横槽位置、副高西脊点位置、南支槽位置、雨凇区700 hPa水汽通量强度、850 hPa冷涡位置、温度垂直结构等密切相关。并在此基础上,建立了湖南省重大雨凇过程概念模型,为雨凇预报提供技术支持。Using the NCEP （2.5 °x2.5 °） reanalysis data, the features of general atmospheric circulation and water vapor flow, which appeared in eight severe icy-rain processes in Hu＇ nan province during 1951 to 2010, are studied. The results show that the six of these severe ice-rain events happened ,in the background of a blocking high in high latitudes, and the other two in the background of more waves in mid-latitudes. The geograph range and the lasting-time of the icy rains are closely related to such climatic conditions, such as the northeast-inclining degree of the middle axis of the blocking high, the location of the horizontal trough to the east of the blocking high, the location of the west end of the ridge of the subtropical Pacific high, the location of a southern trough, as well as the strength of water flux at 700 hPa in the icy rain area, the location of a cold vortex at 850 hPa, and the temperature profile structure, and so on. Based on this analysis, the climatic pattern of icy rain events is established, which possibly could be used as technical support for icy rain forecast.

关 键 词：天气学 雨凇 环流特征 阻塞高压 水汽输送 逆温层 

分 类 号：P434[天文地球—大气科学及气象学]