贵州省印江县暴雨特征初步研究

Preliminary Research on the Characteristics of the Rainstorm for Yinjiang County,Guizhou Province

利用2010—2014年共5 a贵州省印江县17个自动站观测资料和Micaps实况资料,采用相关对比分析、汇总归类等统计方法,分析了印江县暴雨时空分布及天气环流形势特征。结果表明:近5 a来印江县暴雨次数和过程降水量均呈增长趋势,暴雨主要发生在4—7月,且7月最多,占全年累计总数的50%,大暴雨天气过程以2 d居多,最长持续3 d;印江多暴雨区主要集中在印江县中北部、东北部至梵净山西部一带;印江暴雨天气可分为3类环流型,即冷锋+高空槽+切变型、低涡切变+高空短波槽型、台风倒槽型;印江县暴雨与该区域的垂直速度、假相当位温、比湿、水汽通量散度、水汽通量、涡度、K指数、SI指数、LI指数有密切关系。

Based on the 17 Automatic stations observation data and Micaps data from 2010 to 2014,the spatial-temporal distribution and atmospheric circulation features of the rainstorm were researched by using the correlation analysis,statistical method and so on in Yinjiang County. The results show that： The times of rainstorm and Annual precipitation in nearly five years showed a growth trend,the rainstorm mainly occurred in April-July,but in July is the most,which accounts for 50% of the total number of rainstorm. The rainstorm usually ended in two days,and the longest maybe last to three days; Rainstorm region mainly concentrated in the middle of north,North-East and the western region of Fanjing Mountain; Atmospheric circulation of the rainstorm can be classified into three categories,which is cold front＋ upper trough ＋ Shearing,Low vortex Shearing ＋ shortwave trough of high level and typhoon inverted trough; The rainstorm was closely related to the vertical speed,pseudo- equivalent temperature,specific humidity,water vapor flux divergence,moisture flux,vorticity,K index,SI index,and LI index in the rainstorm region.