东亚地区典型极端气候指标未来预估及高温下人口暴露度研究

Future Prediction of Typical Extreme Climatic Indices and Population Exposure to High Temperature in East Asia

基于地球系统模式、CMIP6(第六次全球耦合模式比较计划)温室气体排放和大气成分数据以及人口数据,研究区域均温变化与极端气候指标变化之间的相关关系,进而探讨9种SSPs(共享社会经济路径)-RCPs(典型浓度路径)情景下东亚3种极端气候指标的未来预估和区域高温下人口暴露度的变化及归因。结果表明:1)全球地表均温变化和区域极端气候指标具有稳健的相关关系,可以用于区域极端气候指标的未来预估;2)与基准期1861—1880年相比,未来数十年间东亚地区在5种情景(SSP2-4.5,SSP4-6.0,SSP3-LowNTCF,SSP3-7.0-Baseline和SSP5-8.5-Baseline)下面临持续增加的极端气候风险,而空气污染物减排与控制措施可以显著地降低该风险,不过,气候对温室气体及气溶胶排放控制措施的响应具有一定的时间滞后效应,为预防可能面临的极端气候事件风险,减排及控制措施应提前布局和实施;3)东亚典型区域未来高温下的人口暴露度受气候因子和人口因子共同作用,随时间动态变化且具有明显的区域差异,多数情景下,气候因子对区域高温下人口暴露度的影响逐渐减弱,而人口因子的影响逐渐加强,华南地区高温下的人口暴露度明显高于西南和华中地区,其中气候因子的相对贡献比例也高于后两个地区。

Based on the Earth System Model,greenhouse gas emissions and atmospheric composition of CMIP6 and population data,the correlation between the change of regional mean temperature and extreme climatic indices was studied.Three climatic indices over East Asia under nine SSPs-RCPs scenarios were predicted,and the variation and attribution of population exposure to high temperature were analyzed.The results indicate that 1)there is a robust correlation between the change of global mean temperature and regional extreme climatic indices,which can be used to predict the latter in the future.2)East Asia will experience increasing risk of extreme climate event in the future decades under SSP2-4.5,SSP4-6.0,SSP3-LowNTCF,SSP3-7.0-Baseline and SSP5-8.5-Baseline scenarios.But taking mitigation measures in advance could reduce such risk significantly.3)Future population exposure to high temperature of three typical regions of East Asia,which is affected by both climate and population factors,changes dynamically over time and regions.Under most scenarios,the effects of climate and population factors are gradually weakening and strengthening,respectively.The population exposure to high temperature of Southern China is significantly higher than that of Southwest and Central China,and the relative contribution of climate factors is also higher than that of these two regions.