基于降水距平百分率的广西干旱特征分析

An analysis of characteristics of drought in Guangxi based on precipitation anomaly percentage

利用2004~2015年广西壮族自治区及14个地市逐月降水资料,以降水距平百分率作为干旱等级评价指标,分析广西降水的年际变化、季节变化和空间分布特征。结果表明:广西多年平均降水量桂南﹥桂北﹥桂东﹥桂中﹥桂西;2004~2015年间有6年发生干旱,发生春旱、夏旱、秋旱、冬旱的频率分别为25%、8.33%、41.67%、50%;广西14个地级市发生干旱的平均频率为49.4%。广西发生轻旱、中旱、重旱、特旱的平均频率分别为6%、12.5%、8.3%、22.6%;其中南宁和梧州为轻旱易发城市,贵港、玉林、崇左和河池为中旱易发城市,崇左、河池、百色、来宾为重旱易发城市,河池、百色、崇左、南宁为特旱易发城市。

The annual, seasonal variation and spatial distribution characteristics of precipitation are analyzed by using the monthly precipitation data from 2004-2015 in Guangxi and 14 cities.The time-space distribution characteristics of different grade droughts are analyzed with precipitation anomaly percentage as drought grade evaluation index.The results show that the multi-year average precipitation in Guangxi （ 〉west）;the drought has 6 years from 2004-2015,the occurrence frequency of spring,summer, autumn,winter drought are 25 %,8.33%,41.67%,50%.The average occurrence frequency of drought in 14 cities is 49.4%. The average occurrence frequency of light,moderate,serious,extraordinary drought are 6%,12.5%,8.3%,22.6%.And them.The average occurrence frequency of light drought cities are Nanning and Wuzhou,the average occurrence frequency of moderate drought cities are Guigang,Yulin,Hechi and Chongzuo,the average occurrence frequency of serious drought cities are Chongzuo,Hechi,Baise,Laibin.The average occurrence frequency of extraordinary drought cities are Chongzuo,Hechi,Baise and Nanning.