2008年初贵州低温雨雪凝冻灾害天气成因分析  

Analysis of Guizhou's rare steady weather process of low-temperature with snow and congelation in the beginning of 2008

作　　者：唐延婧[1] 宋丹[1] 

机构地区：[1]贵州省气象科技服务中心,贵阳550002

出　　处：《气象科学》2008年第B12期78-83,共6页Journal of the Meteorological Sciences

摘　　要：利用NECP 2.5°×2.5°的日平均再分析资料和常规观测资料,对2008年1月12日—2月13日期间贵州省历史罕见的持续低温雨雪凝冻天气过程的环流特征及物理量进行了分析,并对中东部凝冻严重的前期和西部凝冻严重的后期做了对比。揭示了此次灾害天气的几个主要天气特征:(1)地面静止锋的位置关系着我省低温雨雪凝冻灾害的区域。(2)500 hPa环流前期和后期影响系统明显不同。过程期间欧亚大陆500 hPa高度场距平呈"北高南低"分布,亚洲区极涡南掉,面积偏大。(3)过程前期850 hPa冷舌明显,等温线密集;后期700 hPa气温降低,有冷舌活动,850 hPa冷舌明显减弱,低温维持。中东部和西部地区冷暖平流垂直方向上的配制不同。强盛的700 hPa暖湿气流是此次过程的主要水汽来源。Using the NECP 2.5°×2.5° daily reanalyzed data and observation data, Guizhou＇s longdrawn infrequent weather process of low-temperature with snow and congelation from Jan. 12, 2008 to Feb. 13 was analyzed on the circumfluence character and physical factor. And a comparison has been made between the previous stage with heavier congelation area in the middle and east, and the later stage with heavier congelation area transferred to the west. So we have drawn some important character of this disaster weather： （ 1 ） The location of stationary front is closely connected to the area of low-temperature with snow and congelation in Guizhou. （2） Circumfluence at 500 hPa had different character at the previous stage and the later stage. Through all of the process, 500 hPa height field in Eurasia had the departure distribution of ＂positive in the north and negative in the south＂, and the area of polar vortex is lager than average in Asia. （3） At the previous stage, the cold tongue at 850 hPa is obvious and dense isotherm. And the later stage had lower temperature and active cold tongue at 700 hPa, while the cold tongue at 850 hPa significantly decreased and kept low temperature. And the temperature advection had different structure of the vertical direction.

关 键 词：低温雨雪冰冻灾害 环流特征 温度平流 暖湿气流 

分 类 号：P426.634[天文地球—大气科学及气象学]