近60年广西夜间降水与暴雨频次的时空特征分析  

Analysis of the spatiotemporal characteristics of nighttime precipitation and heavy rainfall frequency in Guangxi over the past 60 years

作　　者：李秀昌 黄维 黄小燕 韦春霞 吴玉霜 LI Xiuchang;HUANG Wei;HUANG Xiaoyan;WEI Chunxia;WU Yushuang(Yulin Meteorological Bureau,Guangxi Yulin 537000,China;Liuzhou Agricultural Meteorological Experimental Station,Guangxi Liuzhou 545003,China;Guangxi Institute of Meteorological Sciences,Nanning 530022,China;Guangxi Meteorological Observatory,Nanning 530022,China)

机构地区：[1]玉林市气象局,广西玉林537000 [2]柳州市农业气象试验站,广西柳州545003 [3]广西壮族自治区气象科学研究所,南宁530022 [4]广西壮族自治区气象台,南宁530022

出　　处：《气象研究与应用》2023年第4期7-13,共7页Journal of Meteorological Research and Application

基　　金：广西气象科研计划项目(桂气科2023ZL11)。

摘　　要：基于1962—2022年广西91个气象站点逐日08—20时、20时—次日08时的降水数据,综合采用趋势分析和Mann-Kendall突变检验方法,从降水量和频次等角度分析广西近60 a夜间降水、夜间暴雨的时空分布特征。结果表明:(1)广西降水日变化明显,夜雨率有明显的空间差异,主要表现为自西北向东南递减,山区明显高于平原。(2)广西近60 a各地年平均夜间暴雨日数在3.7~13.6 d之间。广西西北部夜间降水强度大。广西大部地区的夜间最大降水量在200~250 mm之间。(3)广西近60 a暴雨日数和夜雨量呈显著增加趋势。特大暴雨发生概率在增加。4—9月是广西夜间暴雨的高发期,最多发生在6月。(4)在广西14个地级市中,河池市夜雨率最高,防城港市夜雨量最大,暴雨贡献率最高。广西夜间降水强度大,夜间暴雨现象显著增加,特别是山区夜间暴雨风险极大。各级气象部门需进一步提高山区夜间暴雨监测预警及服务能力。Using daily precipitation data from 91 stations in Guangxi from 1962 to 2022 at 08:00—20:00and 20:00-08:00,trend analysis and Mann-Kendall were used to analyze the spatiotemporal distribution characteristics of nighttime precipitation and nighttime rainstorm frequency in Guangxi over the past 60 years from the perspectives of precipitation amount and frequency.The results show that:(1)The daily variation of precipitation in Guangxi is significant,with significant spatial differences in nighttime rainfall rates,which is mainly manifested as decreasing from northwest to southeast,with mountainous areas significantly higher than plains.(2)Over nearly 60 years,the annual average number of nightime rainfallstorm days at each station in Guangxi in the past 60 years ranges from 3.7 d to 13.6 d.Northwestern Guangxi experienced stronger nighttime precipitation generally,with the maximum nighttime precipitation in most areas of Guangxi ranging from 200~250mm.(3)Statistics show significant increases in rainfallstorm days and the amount of nighttime rainfal in the past60 years.The probability of occurrence of extreme rainstorms is growing,with April-September being the peak season of nighttime rainstorms in Guangxi,and the most nighttime rainstorms occurring in June.(4)Among Guangxi's 14 prefecture-level cities,Hechi has the highest rate of nocturnal rainfall,and Fangchenggang has the highest amount of nocturnal rainfall and the highest contribution to rainstorms.The intensity of nighttime precipitation in Guangxi is high,and the phenomenon of nighttime rainstorm increases significantly,especially in mountainous areas where the risk of nighttime rainstorms is extremely high.Meteorological departments at all levels need to further improve the monitoring,warning of nighttime rainstorms in mountainous areas as well as their service capabilities.

关 键 词：广西 夜间降水 夜间暴雨 气候趋势 

分 类 号：P426[天文地球—大气科学及气象学]