海南省台风和暴雨灾害年景评估及其变化分析

Annual Assessment and Variation Analysis of Typhoon and Rainstorm Disaster in Hainan Province

利用海南省1982—2017年的气象观测资料、台风和暴雨灾情资料以及社会经济数据,构建了可较好去除物价上涨因素的灾害影响综合评估指数,并按照百分位法确定了灾害的气候年景等级阈值,给出了历年灾害年景的评估结果,分析了灾害年景的变化及其影响因素,结果表明:(1)所研制的灾害年景评估方法可以客观地反映海南省台风和暴雨灾害的年景分布;(2)近36年海南省台风和暴雨灾害年景等级年际间的波动剧烈,且在20世纪80年代后期至20世纪末存在3～6年的显著周期,21世纪初期存在短暂的4～5年和2～3年的显著周期.在年代际变化方面,1982—1996年期间,灾害年景等级基本处于相对偏高的阶段,1997—2017年灾害等级进入相对偏低的阶段,但未发生突变;(3)近36年来,尽管登陆海南岛的热带气旋的年最强登陆强度有增强趋势,热带气旋所造成的重度区域性暴雨过程的年频次亦有增加趋势,但由于热带气旋年登陆频数的减少以及防灾减灾能力的增强,台风和暴雨灾害所造成的人员死亡、房屋倒塌以及直接经济损失均有减少趋势,因而导致了台风和暴雨灾害年景有转好趋势;(4)海南省台风和暴雨灾害年景的年际变化与登陆海南岛的热带气旋年频数、年最强登陆强度以及热带气旋造成的重度以上区域性暴雨过程的年频次密切相关.

Based on the meteorological observation data,typhoon and rainstorm disaster data and socio-economic data from 1982 to 2017 in Hainan Province,in the report,a composite index for damage caused by typhoon and rainstorm was constructed,which can better remove the influence of rising price. According to percentile method,the threshold value of the annual disaster assessment was also determined. The assessment results of annual disaster were proposed,and its variations and influence factors were analyzed. The results showed that:( 1) Annual disaster assessment method we developed can objectively reflect the distribution of typhoon and rainstorm disasters in Hainan Province.( 2) In the past 36 years,annual disaster situation grade of typhoon and rainstorm in Hainan Province has significant fluctuations in the inter-annual scale. It appears prominent periods of 3 ~ 6years from the late 1980 s to the end of the 20 th century and short significant periods of 4 ~ 5 years and 2 ~ 3years in the early 21 st century. In terms of inter-decadal variations,the grade of disasters was basically at a relatively high stage from 1982 to 1996,and at a relatively low stage from 1997 to 2017,but no mutation occurred.( 3) In the past 36 years,although the annual strongest landing intensity of tropical cyclones landing on Hainan Island tends to increase and the frequency of heavy regional rainstorms caused by tropical cyclones has increased,the annual disaster situation of typhoon and rainstorm have turned better. This is due to the reduction of the annual frequency of tropical cyclones landing and the enhancement of disaster prevention and reduction capabilities,which lead to the decrease of the number of deaths,the area of collapsed houses and the direct economic loss rate of typhoon and rainstorm disasters.( 4) The inter-annual variation of typhoon and rainstorm disaster was closely related to the annual frequency of tropical cyclones landing on Hainan Island,the annual strongest landing strength of tropical cyclones,and the annual frequency of severe regional rainstorms caused by tropical cyclones.