近38年安徽省夏季降水日数和强度的分布与变化特征

选用1971～2008年安徽省78个地面气象站的观测资料，分析夏季降水和暴雨的气候变化规律。从结果来看安徽省夏季降水主要受到地理位置、地形地貌和风、温、湿等气象因素的影响。根据主要影响因子的不同，按照降水特性以及行政边界将安徽省划分成了10个区，不同区域内降水特征和分布结构各有差异。在时间变化上，雨日出现概率有下降的趋势，但暴雨日比重和降水量均有升高的变化特征。综合而言，安徽省的降水朝着具有局地性、突发性的强降水过程方面发展，从而导致部分区域内突发性暴雨过程频发

CHARACTERISTICS OF PRECIPITATION DAYS AND INTENSITY OF ANHUI PROVINCE IN SUMMER DURING RECENT 38 YEARS

Anhui Province is a special region for climate in China as it is over two climatic zones.The characteristics and influential factors of precipitation in different fields are various.The main object of this study is to investigate the distribution and find out the influential factors of precipitation in summer over Anhui.For this goal,the meteorological observation data of 78 stations form 1971 to 2008 were collected and analyzed.During the analysis,the percent of different intensity rainfall and the ratio between storm days and rainfall days were calculated.Finally,the temporal variations of meteorological observation data were analyzed.The results show that rainfall were effected by several factors,such as terrain,moisture,temperature,wind and so on.According to the difference of position and influential factors,Anhui Province was divided into 10 regions,which were climatic storm region,climatic rain region,weakly rain region along Huaihe River,lee weakly rain region on the north of the Yangtze River,hilly convective rain region,Dabieshan topographic rain region,high temperature storm region,lee weakly rain region on the north of the Yangtze River,irregular rain region along the Yangtze River and Wannan topographic storm region.On the other hand,there were typical characters in rainfall temporal variety.That is the percent of storm cases and ratio of storms to rainfall were increasing with the decreasing of rainfall cases from 1971.For the analysis of spatial and temporal characters of precipitation in Anhui Province,two main views could be concluded.First,with the changing of climate,the precipitation of Anhui province was became heterogeneous in spatial and temporal distribution.Second,the heavy rain cases such as storm occurred more frequently than before.