基于GIS的云南省1km精细化暴雨灾害风险评估

Rainstorm Disaster Risk Assessment in Yunnan Based on 1km Grid in GIS

为了加强暴雨相关的防灾减灾工作的科学性,本文基于云南省126个国家气象站2010—2019年10年的逐时降水资料和基础地理信息数据,从暴雨灾害致灾因子危险性、孕灾环境敏感性和承灾体易损性3个方面,建立暴雨灾害风险评估模型,利用熵值法、自然断点法、ArcGIS插值和栅格分析方法,实现云南省暴雨灾害风险的区划评估。结果显示:(1)暴雨灾害高风险区主要集中于云南南部,包括西双版纳州、普洱市、红河南部、德宏州及北部地区;(2)迪庆州、怒江州、丽江市北部等地暴雨灾害风险等级较低;(3)全省暴雨灾害高风险区、次高风险区面积占比分别为7.05%、25.22%,低风险区、次低风险区面积占比分别为10.32%、21.86%。使用2020年暴雨灾害次数、暴雨日对区划评估结果进行检验表明,区划评估结果具有科学合理性。

In order to reinforce the scientific part of the prevention and mitigation of rainstorm disasters,based on the hourly precipitation data of 126 national weather stations from 2010 to 2019 and basic geographic information,we build the model of risk assessment of rainstorm disasters through three aspects:the danger factor of disaster-inducing,the sensitivity of disaster-pregnant environment and the vulnerability of the disaster-bearing body.To realize the division of risk areas relating to rainstorm disasters in Yunnan,we apply four methods:maximum entropy,natural break point,ArcGis interpolation and grid analysis.Results show that the high-risk areas of rainstorm disasters centre in the southern Yunnan,including Xishuangbanna,Pu’er,the southern Honghe and Dehong.However,Diqing,Nujiang and the northern Lijiang are lower-risk areas.Throughout the whole rainstorm disaster in Yunnan,high-risk and secondary high-risk areas account for 7.05%and 25.22%,and low-risk and secondary low-risk areas account for 10.32%and 21.86%.Using the data,such as the times of rainstorm disasters in 2020 and the testing results of area-division of rainstorm disasters,it is shown that the area-division assessment is scientific and rational.