勐腊县雷暴气候变化特征分析

利用勐腊县1957—2011年雷暴资料,采用气候趋势系数、倾向率和保证率等气候诊断方法,探讨了勐腊县近55 a雷暴的气候趋势、时空分布特点及不同保证率下的雷暴初终日期.结果表明,勐腊县各月均有雷暴发生,雷暴日数发生最多是4—10月,占全年的90.2%.勐腊县年雷暴年际变化呈减少趋势,减幅最明显的是夏季和秋季,每10 a的雷暴日数减少4 d左右.勐腊县雷暴初日有退后的趋势,80%保证率的雷暴初日日期是1月12日,终日日期是12月16日,5%保证率的雷暴初日日期是3月19日,终日日期是10月7日,50%保证率的雷暴初日日期是1月31日,终日日期是11月13日.

Analysis on climate change of thunderstorm in Mengla,Yunnan

Based on the data of thunderstorms in Mengla from 1957 to 2011,the climatological variation trends,temporal-spatial distribution and initial/ending dates of thunderstorms under different assurance ratios in the past 55 years have been analyzed in the light of climatic tendency coefficient,variation trends and assurance rations.The results show that the thunderstorms strike each month in Mengla,the thunderstorm days occur mostly from April to October,accounting for 90.2% of the year.The annual number of thunderstom days has a decreasing trend,mainly in summer and autumn,and there are decreases of about four thunderstorm days per decade in Mengla.For an assurance ratio of 80%,the initial thunderstorm date begins on January 12th and ends on December 16th.The initial thunderstorm date has a receding trend.For an assurance ratio of 5%,the initial thunderstorm date occurs on March 19th and the ending date occurs on October 7th.For an assurance ratio of 50%,the initial thunderstorm date occurs on January 31th and the ending date occurs on November 13th.