广西西南部干旱指数分析

利用崇左市7个气象站1965-2010年每日的降水资料及雨日,计算三个干旱监测指标:综合干旱指数、降水距平百分率及累计降水距平、标准化降水指数(SPI),结果以用于综合监测某时段旱涝程度。三个干旱监测指标计算结果与灾情实况对比分析表明,综合干旱指数和降水距平百分率都能很好地反映广西西南部的干旱情况;标准化降水指数(SPI)采用的是Γ分布概率来描述降水量的变化,只计算降水为0时的概率,因而与实际有差距。如果按广西西南部的实际情况,统计降水≥1.0mm的概率,则计算出的结果与实况比较接近。

Analysis of Drought Index in Southwestern Guangxi

By using Chongzuo seven weather stations 1965-2010 daily precipitation data and rain days,calculation the three drought monitoring indicators: comprehensive drought index,the percentage of the precipitation anomaly and accumulated precipitation anomaly,the Standardized Precipitation Index(SPI),results for the integrated monitoring period dryness.Three drought monitoring indicators calculated results with disaster live comparative analysis shows that comprehensive drought index and the precipitation anomaly can be a good reflection of the drought in southwestern Guangxi;Standardized Precipitation Index(SPI) is a Γ distribution of probability to describe the precipitation the amount of change,only the precipitation probability 0:0,and therefore the actual gap.If the actual situation of southwestern Guangxi,statistical precipitation ≥ 1.0mm probability,then the calculated results and live relatively close to.