Spatial and Temporal Distribution Characteristics of Rainstorm and Flood Disasters in Yunnan in Recent 30 Years
Based on the data of 3 951 rainstorm and flood disasters in Yunnan Province from 1990 to 2020 collected by counties,the spatial and temporal distribution characteristics of rainstorm and flood disasters in the past 30 years were analyzed by using mathematical statistics,Morlet function wavelet transform,ArcGIS three-dimensional perspective,etc.The results show that the frequency of rainstorm and flood disasters in Yunnan Province has increased linearly in the past 30 years,with less disaster years and more disaster years appearing alternately;The affected area of crops,collapse of houses,and death toll show a linear decrease,while direct economic losses show a linear increase.However,the pro-portion of direct economic losses to the province's GDP shows a linear decrease in that year.The frequency of disasters has obvious cyclical characteristics;The spatial distribution at the county level has obvious regional characteristics;The areas with the highest and lowest frequency of occurrence have a high degree of overlap with the areas with the heaviest and lightest disasters.Among the rainstorm and flood disaster indicators,the distribution trend of prefectures and cities is that Zhaotong in the northeast of Yunnan is the highest value,and Diqing in the northwest of Yunnan is the lowest val-ue,which shows that human activities are an important factor affecting the degree of rainstorm and flood disaster.The research results can provide support for disaster prevention and mitigation countermeasure research,rainstorm and flood disaster risk assessment and zoning.
rainstorm and flood disasterlinear trendMorlet wavelet analysis3D perspective view
万方数据
维普
