Vulnerable Population Exposure to Heatwaves in the Pearl River Basin Based on Comfort Index of Human Body
LI Yun
SU Buda
HUANG Jinlong
CHEN Sirong
DONG Baohua
JIANG Tong
Abstract：The Pearl River Basin is a climate-sensitive area where climate warming leads to frequent heatwave disasters.The Comfort Index of Human Body integrates multiple meteorological elements to better assess the impact of heatwaves on human health.Based on the index for defining heatwaves,meteorological observations and five CMIP6 climate model data containing seven SSPs were used to analyse the characteristics of summer heatwaves and exposed vulnerable population in the Pearl River Basin during the historical period(1961-2022)and the 21st century's near-term(2021-2040),mid-term(2041-2060),and end-term(2081-2100).The results show:(1)From 1961 to 2022,the maximum number of summer heatwave days in the Pearl River Basin can be up to 42 days,with the longest duration lasting up to 16 days.The average annual heatwave-affected area is approximately 165,000 km²,with the Pearl River Delta experiencing the most severe heatwaves.(2)In the near,mid,and end terms of the 21st century,compared to the baseline period(1995-2014),the basin-wide average number of summer heatwave days will increase by approximately 7-9 days,11-29 days,and 5-75 days,respectively,with the maximum duration increasing by about 2-4 days,5-10 days,and 2-50 days.The increase is more significant in the high-altitude areas upstream of the Pearl River Basin;the heatwave-affected area continues to expand,and the heatwaves in the late 21st century may influence the entire basin.(3)From 1961 to 2022,the annual average exposed vulnerable population in summer was about 28.6 million person-days,and the maximum in the Pearl River Delta can reach 108 million person-days in 2019.Future vulnerable population exposure will increase significantly,about 6.4-7.8 times,18.5-38.4 times,and 11.9-117.7 times of the baseline period in the near,mid,and end terms,respectively,especially in the Eastern Pearl River Basin.(4)The combined effect of climate and population change is the dominant factor determining the future changes in the exposure of vulnerable populations in the Pearl River Basin,and its contribution rate gradually increases over time.There is an urgent need to strengthen heatwave prevention measures in the future.
Keywords：heatwavesComfort Index of Human Bodyvulnerable population exposurecontribution ratePearl River Basin
Publication Date：2025-12-31
Online Publishing Date：2026-01-12(First online date of this platform, not the publication date of the document)
Pages：13( 884-896 )