南宁市极端天气气候事件频率和强度变化

Frequency and Intensity Change of Extreme Weather-Climate Events in Nanning City

采用南宁市城区1951～2005年的月降雨量及暴雨、高温、大风、雷暴、大雾的年日数资料，统计干旱、暴雨、高温等极端天气气候事件的出现频率、强度，应用低通滤波和线性倾向估计方法，分析极端天气气候事件出现频率的演变趋势。结果显示，55年来，南宁市城区干旱频率变化率为0．0127％／lOa，呈平稳变化趋势，但强度增大；暴雨日数变化率为0．276d／lOa，呈增多态势，大暴雨频率为0．275％／lOa，呈增大趋势；高温频率线性倾向为0．1％／lOa，呈平稳趋势变化；大风、雷暴、浓雾频率的线性倾向分别为一0．5％／10a，一0．13％／lOa和一0．3％／lOa，均呈显著减小趋势。

With the analysis of monthly rainfall and the date data of rainstorm,high temperature, thunderstorm,gale,fog between 1951 and 2005 in Nanning city, the frequency and intensity of extreme weather-climate events such as drought, rainstorm, high temperature, etc. were educed. Though lowpass filters and linear-trend evaluation, the frequency trend of the extreme weatherclimate events were analyzed. The result shows that （1） the frequency of drought is stable in 0. 0127%/10a with intensity aggravating in the last 55 years. （2） the frequency of rainstorm （heavy rainstorm） is 0. 276d/10a（0.275%/10a）with an ascending trend. （3） the linear frequencies of high temperature is stable in 0. 1%//00/10a. （4） Thunderstorm（gale ,fog） has a reducing trend with the linear tendency of -0. 5%/10a（-0. 13%/10a and -0.3%/10a）.