面向区划的台风灾害综合风险评价——以广东省台风灾害人口与经济风险为例

Comprehensive risk assessment of typhoon for regionalization——A case of population and economic risk in Guangdong Province

中国是世界上受台风影响最严重的区域之一,开展系统的台风灾害风险评估及区域规律总结与区划研究,对分区灾害风险防范理论与实践均具有重要意义。本文分析了自然灾害风险综合区划的需求,并以广东省为例,在区域灾害系统理论指导下综合评价了广东省台风灾害人口与经济风险。评价模型包括台风综合致灾因子强度、人口与经济承灾体社会脆弱性、暴露度3个要素。风险评价结果利用多重现期情景下的地学图谱方法表达,包括5、10、20、50和100年一遇的情景。研究表明:①多个情景下台风综合致灾因子强度从沿海-内陆逐级递减,高强度区域主要集中于沿海部分以及内陆沿河流区域;②人口与经济承灾体高脆弱区域主要分布于珠三角地区,粤东城市群区域,粤北和粤西的城镇区;③人口与经济高暴露区域集中在珠三角、粤东、粤西城市城镇区;④台风灾害风险等级从沿海到内陆逐渐降低,5个重现期下中高风险等级区均集中于珠三角一带、次高级中心在粤东潮州-汕头城区一带、粤西的湛江-茂名城区一带。本文的台风灾害风险评价结果具有多情景、系统性的特点,可为广东区域台风灾害人口与经济风险的综合区划提供科学依据。

China is the most seriously affected area by typhoons.It is of great significance for the theory and practice of zonal disaster risk prevention to carry out a systematic risk assessment of typhoon disasters and regional law summary and regionalization research.Based on the regional disaster system theory,we systematically evaluate the population and economic risk of typhoon disasters in Guangdong Province and express the results using a geo-graph method of the return period,to support the future work of typhoon disaster risk regionalization.In the model,typhoon hazards include wind,heavy rain,and flood.The evaluationmodel includes three factors:typhoon hazard intensity,the social vulnerability of the population and economic victims,and the extent of exposure.The scenarios include 5-year,10-year,20-year,50-year,and 100-year return periods.The results show:1)the hazard intensity decreases gradually from coastal to inland for each scenario,i.e.,intensive hazards mainly concentrate in coastal areas and inland areas along rivers.2)the high vulnerability is mainly distributed in urban areas of the Pearl River Delta,East,North,and West Guangdong.3)the high exposure is mainly concentrated in the Pearl River Delta,East,and West Guangdong cities.4)the risk gradually decreases from coastal to inland,in five scenarios high-risk areas are concentrated in the Pearl River Delta,and the secondary high-level centers are in the Chaozhou,Shantou urban area in eastern Guangdong,and the Zhanjiang,Maoming urban area in western Guangdong.These multi-scenario and systematic results could be the basis of the following research on the regionalization of natural disaster risk.