Risk Division Of Drought Disaster In Hangzhou City

Drought disaster is the global high frequent and serious influence. The impact of drought climate has the characteristics of long duration and wide range.It has great influence on the people’s living standards and economic activities, what provides most on Agricultural Production..Hangzhou which is located in the northeast coast of Zhejiang is one of the relatively serious Drought disaster areas in China. According to Hangzhou meteorological related data and statistical analysis, the minimum precipitation anomaly percentage is-84.72%which is recorded in1962of Jiande’s Winter drought period.Meanwhile, the longest consecutive rainless days is52d which is recorded in2004of Hangzhou urban’s Autumn drought period. The continuous drought happened most in1967,when6stations all appeared3drought in a row except Jiande. In addition to Jiande,all stations have appeared extreme drought.According to the1984-2008Drought disaster data, this paper assesses the Drought disasters caused loss through the selection of three indexes which are the crop area losses and the direct economic losses. It shows a quantitative evaluation on the situation of Drought disaster damage and space losses based on the grey relation model. Based on the precipitation data from Hangzhou City during the period from1959to2010and combined with the natural geographic and the society economic factors, according to the natural disaster system theory, this study builds a set Drought disaster assessment model of hazard factors, hazard including environment, hazard-affected body and disaster prevention ability.In this paper, it uses the GIS spatial analysis technique to study space laminated analysis of the index and uses the fuzzy comprehensive evaluation method to analyze Drought disaster risk situation in the selected area on the base of theory of Drought disaster formation, Drought disaster development and the spread of the disaster and proper disaster risk evaluation index. The author produces the Hangzhou municipal Drought disaster risk diagram with the100m*100m grid for basic evaluation unit and divides Hangzhou into five risk categories which are high, secondary high, medium, secondary low and low respectively.Division results show that northwest of Chunan,south central of Jiande, central section of Tonglu and Linan, Yuhang district and urban of Hangzhou city take higher risk level in Summer drought period and Autumn drought period.For Winter drought period, northwest of Chunan, south section of Linan, northl section of Tonglu and Fuyang show relatively higher risk level.Finally, according to the Drought disaster data in Hangzhou, the verified evidence shows that the risk division results are in accordance with the regional disaster distribution.