不同碳中和路径下复合型热浪与人口暴露度变化的对比研究OA

Based on 5 global models from the Coupled Model Intercomparison Project Phase 6(CMIP6),this study presents the projected changes in summer compound heatwaves and corresponding population exposure over China.The projected changes during the carbon neutrality periods under SSP1-1.9 and SSP 1-2.6 scenarios are analyzed relative to the historical period(1995-2014),and the differences between them are also compared.The results show that,during both the early carbon neutrality period(2032-2051)and the late carbon neutrality period(2054-2073),China is projected to experience increased and intensified compound heatwaves relative to the historical period,and the increase and intensification are greater in the late carbon neutrality period.Specifically,larger increases in compound heatwave days(HWD)are distributed in Southeastern China and Northwest China,while the greatest increases in mean daily intensity(HWI)and maximum daily intensity(HWImax)occur in Northwest China and North China.Furthermore,the likelihoods of extreme compound heatwaves(historically 1-in-50-year)are projected to increase,among which the largest increases are in HWD and mainly distributed in Northwest China and the Yangtze River valley.The increased HWD and HWI are expected to cause a significant increase in population exposure,particularly in the Yangtze River valley,Tibetan Plateau,and Northwest China.Comparatively,achieving carbon neutrality earlier is likely to reduce the increases in HWD and HWImax over China by 2.29 days and 0.44 ℃,respectively.For the likelihoods of extreme HWD and extreme HWImax,the increases during the early carbon neutrality period are 5.5 times and 3.8 times smaller than those during the late carbon neutrality period.Correspondingly,early carbon neutrality would prevent additional increases of approximately 1.1-fold and 0.8-fold in population exposure to compound heatwaves and extreme compound heatwaves in China,respectively.