近40年桂林市雷暴的变化特征及成因分析

根据广西桂林市13个气象观测站1971～2008年各月雷暴日数资料，研究了桂林市雷暴的空间分布、季节变化特征、物理量特征和天气形势。结果表明，雷暴分布趋势为自中部向北部及东南部递减，桂林中部的桂林城区、临桂县及永福县年雷暴日数最多，北部的资源县和灌阳县年雷暴日数最少；桂林市雷暴日的出现有着明显的月、季变化，主要集中在春、夏季，4～8月份为桂林多雷暴月，在8月达最大值，而冬季发生的概率较低，12月为最小值；桂林的雷暴与冷锋、高空槽及冷涡等天气系统密切相关，是大尺度天气系统与局地聚积的湿热潜能共同作用的结果。

Analysis on Variation Characteristics of Thunderstorm and Its Cause in Guilin City in Recent 40 Years

According to number of thunderstorm days of 13 meteorological stations in each month from 1971 to 2008 in Guilin City of Guangxi,spatial distribution,seasonal variation characteristics,physical quantity characteristics and weather situation of thunderstorm in Guilin City were studied.Results showed that the thunderstorm was decreased from central part to north and southeast parts.Annual number of thunderstorm days in Guilin city,Lingui County and Yongfu County of central Guilin was the maximum while that in...