2015年茂名主要气象灾害和最大日降水量重现期计算  

Analysis of Main Meteorological Disasters in Maoming in 2015 and Calculation of Return Periods of Maximum Daily Rainfall Amount

作　　者：李英[1] 陈蔚烨 宋祖钦 李东萍[1] 谢韶 

机构地区：[1]化州市气象局,广东化州525100 [2]茂名市气象局,广东茂名525000

出　　处：《广东气象》2016年第6期38-41,共4页Guangdong Meteorology

摘　　要：利用茂名1958—2015年常规气象观测资料对2015年茂名气候特征进行分析,研究表明:2015年茂名平均气温为23.9℃,比常年偏高0.8℃;年平均雨量为1 799.0 mm,比常年偏多3%,属于正常。年平均日照时数为1 901.7 h,比常年同期偏多3%。对年内所发生的主要气象灾害按照暴雨、台风、干旱进行分类统计,并对汛期3场暴雨和台风彩虹过程进行了环流分析。指出2015年副高面积较常年同期偏大、强度偏强、西脊点偏西是茂名气象灾害频繁的主要原因之一。通过百分位法和最大日降水指数分析,信宜最大日降水阀值确定7·21降水事件为极端降水事件,用指数曲线分布理论计算重现期,信宜50年一遇的最大日降水量为261.3 mm,100年一遇的最大日降水量为293.1 mm。With conventional meteorological observation data in 1958-2015, we analyzed the climatolog- ical characteristics of Maoming in 2015. The result is shown as follows. The annual mean temperature is 23.9 ℃ , 0. 8 ℃ higher than normal, the annual mean rainfall amount is 1 799.0 mm, 3 % more than usu- al, which is within the normal range, and the annual mean duration of sunshine is 1 901.7 h, 3% more than the same period of past years. Heavy rains, typhoons and droughts of 2015 were categorized for statisti- cal study and three processes of heavy rain during the raining season and Typhoon Mujigae were analyzed in terms of associated patterns of circulation. It is found that one of the main reasons of frequent occurrence of meteorological disasters in Maoming in 2015 was that the subtropical high was anomalously larger and stron- ger, and its westernmost point of ridge was anomalously westward, than usual. Analyzing through the per- centile approach and a maximum daily rainfall index, we determined that the July 20 rain of Xinyi was an e- vent of extreme rainfall by the threshold of maximum daily rainfall. Applying the theory of index curve distri- bution, we know that the maximum daily rainfall amount for Xinyi is 261.3 mm for a 50-year return period and 293.1 mm for a 100-year return period.

关 键 词：气候学 气象灾害 极端降水 重现期 2015年 茂名 

分 类 号：P46[天文地球—大气科学及气象学]