1980—2019年新疆南部不同强度暴雨洪水灾害的空间分布和时间变化特征

以1980—2019年新疆南部出现的暴雨洪水灾害事件造成的死亡人数、倒塌房屋数、倒塌棚圈数、牲畜死亡数、受灾面积作为灾情要素，采用比值权重法和无量纲化线性求和，构建了暴雨洪水灾害事件的灾损指数。根据灾损指数，采用百分位数法将每次暴雨洪水灾害事件定量划分为一般、较重、严重、特重四个等级。结果表明：新疆南部暴雨洪水事件在塔里木盆地北缘多于南缘，西部多于东部，高值区集中在阿克苏地区、喀什地区、克孜勒苏柯尔克孜自治州一带；暴雨洪水事件多发在3—10月，年出现次数呈现明显上升趋势，增幅为8次·（10a）^-1，主要表现为一般性灾害发生频次的增加；新疆南部暴雨洪水灾害年平均灾损指数在1985年和1999年发生两次突变，平均值表现出“低—高—低”阶段性变化；暴雨洪水灾害发生次数与3—10月降水量、大雨发生日数、暴雨发生日数密切相关。近40年来新疆南部降水量的增多，导致暴雨洪水灾害次数增加；年平均灾损指数与特重和严重灾害发生次数关系密切，后者对其贡献率达87%。

Spatial distribution and temporal variation characteristics of rainstorm flood disasters with different intensities in southern Xinjiang from 1980 to 2019

Based on the number of deaths， collapsed houses， collapsed sheds， livestock deaths， and the disaster area caused by rainstorm flood disasters in southern Xinjiang between 1980 and 2019， the ratio weight method and the dimensionless linear summation method are used to construct the disaster index of rainstorm flood disaster events. According to the disaster index， rainstorm flood disaster events can be divided into four grades by percentile method： general， heavy， severe， and extra severe. The results show that： The rainstorm flood events in southern Xinjiang are more in northern margin of the Tarim Basin than in southern margin， and more in western than in eastern， and the high value areas are distributed in Aksu Prefecture， Kashgar Prefecture and Kizilsu Kirgiz Autonomous Prefecture. The rainstorm flood events in southern Xinjiang mostly occurred from March to October， and the annual average occurrence frequency showed an obvious upward trend with an increase of 8 times per ten years， which mainly performed the increase in frequency of general disasters. The rainstorm flood disaster index had two mutations in 1985 and 1999， and the disaster loss index showed a “low-high-low” periodic change. The frequency of rainstorm flood disasters is closely related to precipitation， days of heavy rain and rainstorm in southern Xinjiang from March to October. On the whole， the increase of precipitation in southern Xinjiang in recent 40 years has led to the increase of rainstorm flood disasters， which mainly performed the raise of general rainstorm flood events. The average annual disaster loss index is closely related to the number of severe and extra severe disasters， which contributed 87% to it.