长江中下游地区洪涝灾害风险性评估

Risk Assessment of Flood Disaster in the Mid-lower Reaches of the Yangtze

  • 摘要: 基于长江中下游地区2000—2008年湖北、湖南、江西、安徽、江苏、浙江6个省的洪涝灾情资料 (由于上海市洪涝灾情较轻未列入分析范围),运用灰色关联度法对该区域各省每年洪涝受灾情况进行量化,建立洪涝综合灾情指数。基于该指数,采用信息扩散理论评估模型对该区的洪涝灾害进行风险性评估,结果表明:各省洪涝灾害风险差异明显;该地区洪涝中灾频发,几乎1~2年就会遭遇其危害,安徽、湖北以及湖南发生大灾的可能性最大;江苏、浙江次之;江西遭遇大灾的概率相对较小。这一评估结果与近9年实际洪涝灾情统计资料相吻合,说明所用评估模型在处理不完备信息方面确有优势,可以推广应用。

     

    Abstract: Flood disasters caused by heavy rain events occur frequently in the mid-lower reaches of the Yangtze in monsoonal rainy season. The risk of heavy rain events is an important topic in meteorological research in China. Therefore, risk rank of flood disaster in six provinces in the mid-lower reaches of the Yangtze (Hubei, Hunan, Anhui, Jiangxi, Jiangsu and Zhejiang) are assessed based on most recently updated meteorological disaster losses dataset collected by the Ministry of Civil Affairs, National Disaster Reduction Centre of China from 2000 to 2008.First, losses due to flood disasters are classified and quantified by using the method of grey association analysis. The results show that the grey association method is reasonable in disaster situation grading and loss ranking, and the results are basically in agreement with the actual situation. Then an integrated index series in the recent 9 years is established. In addition, the model is very practical and flexible because the numbers of the grade indexes are not limited. Second, since there are not enough integrated historical disaster indexes, an information diffusion based fuzzy method is introduced to optimize the historical disaster data and then the risk in each province is assessed individually. The risk rank results show substantial difference in these provinces. Although medium risk is universal in all the provinces with the occurrence probability of once in one to two years, high risk is relatively more frequent in three provinces, Anhui, Hubei and Hunan, which approximately tallies with the practical situation. This also suggests an efficiency of the present risk-assessment model in processing inadequately long records and deserves extensive use.

     

/

返回文章
返回