近30年石羊河流域气象灾害特征及风险评估技术研究

通过对石羊河流域气象灾害及灾情特征进行分析、研究和评估，在全面、深入了解各类致灾灾种、灾害程度的基础上，为该区防灾减灾和地方经济服务提供决策依据。利用甘肃省武威市1984—2013年气象灾害灾情等相关资料，详细分析了该区气象灾害和灾情特征。结果表明：近30年该区发生较严重的气象灾害有冻害、干旱、大风沙尘暴等，灾害出现次数与经济损失不呈正比。不计物价及货币升值率等因素，各灾种（除干旱）造成的经济损失基本呈逐年上升趋势；但综合考虑国民生产总值(GDP)的变化后，灾害经济损失呈波动下降趋势。采用“拉开档次”法求得气象灾害损失综合指数，再分别用“变量偏离法”和“聚类分析法”对其进行分级评估，显示二者评估结果基本一致，与实况相吻合。

Research on the Characteristics of Meteorological Disasters and Risk Assessment Technology in Shiyang River Basin in Recent 30 Years

The paper aims to provide decision basis for disaster prevention and reduction, and to serve the local economy by comprehensive analysis of the disaster type and degree. The authors researched and evaluated Shiyang River Basin’ meteorological disasters and their characteristics by using meteorological disasters census data from 1984 to 2013 in Wuwei. The results showed that the meteorological disasters mainly included freezing injury, drought and gale sandstorms in nearly 30 years,and the economic losses were not proportional to the number of disasters. Economic losses caused by disasters (except drought) showed an upward trend in fluctuations excluding price and currency appreciation rates. Considering the change in gross domestic product (GDP), the losses trend declined in fluctuations. By using ‘scatter’ method to obtain meteorological disaster losses composite index, the authors graded the index by variable deviation and clustering analysis method, evaluation results were basically the same and fully consistent with the fact.