城市极端高温-热岛效应-臭氧污染的协同作用及其健康风险评估与预测研究—以杭州市为例

With climate change and urbanization, extreme heat events have become more frequent and intense in urban areas. Heat wave has been a leading cause of weather related human mortality in many countries and given rise to dramatic negative effects on the health of urban residents and the economy. Extreme heat health risk assessment is attracting widespread attention of the academic research community. However, existing researches on extreme heat health risk assessment and projection in urban areas rarely consider the synergistic effect of urban heat island and ozone pollution and the vulnerability and adaptive capacity of urban residents. In present project, we collected meteorological data from a dense network of automatic weather stations, air pollution data from air quality monitoring network of Hangzhou city, mortality data from Zhejiang Provincial Center for Disease Control and Prevention, and socioeconomic statistic data. Using technological means of weather diagnostic, GIS spatial analysis, and numerical experiments of WRF/UCM-Chem, the influencing mechanisms between extreme high temperature-urban heat island-ozone will be investigated. Based on epidemiological statistics, we will quantitatively analyze the exposure-response function between extreme heat and ozone pollution and mortality, respectively. More importantly, we will investigate whether extreme high temperature and ozone pollution have synergistic effects on excess mortality in Hangzhou City. This project will improve the assessment framework and methodology for urban heat health risk assessment. An index system combining environmental indicators (such as air temperature, ozone, and vegetation), demographic indicators (such as age, gender, and education level), and socioeconomic indicators (such as household income and neighborhood stability) will be built for quantitative extreme heat risk assessment. Climate change may lead to both increased heat and ozone levels in urban areas in the near future. To assess potential human health impacts of these changes, the coupled WRF/UCM-Chem model will be further used to project the urban climate and ozone concentrations in the 2050s considering both climate change and urbanization development. The mortality transfer functions for summer heat and ozone will be developed and applied in the regional health risk projection considering the synergistic effect for the Hangzhou metropolitan region. This study will provide theoretical and methodological support for multi-disciplinary crossing researches which is in urgent need on the health impacts of extreme climate. The spatial risk assessment methodology will highlight potential heat health risk areas and build the foundations for more targeted health interventions and climate change adaptation strategies.

高温热浪严重威胁人群健康，城市高温灾害健康风险评估和预测逐渐得到重视。然而，已有研究很少考虑热浪期间城市热岛效应和臭氧污染的协同影响，也缺乏针对城市居民承灾体的脆弱性和适应能力评估。本项目基于杭州市的臭氧和气象观测数据、社会经济和死亡统计数据，利用天气气候诊断、数值模拟、环境流行病学统计、GIS空间分析等技术，揭示夏季城市高温-热岛效应-臭氧之间的作用机理，完善城市高温灾害风险评估概念框架并梳理其相应指标体系，将耦合城市冠层模式（UCM）的中尺度大气动力/化学传输模式WRF-Chem、高温-臭氧协同作用下人群健康暴露-反应定量关系模型以及人口空间分布模型等进行有机整合，预估未来气候变化和城市化共同影响下高温-臭氧协同作用造成的城市居民健康风险。以期为我国亟需开展的极端天气事件影响人群健康研究提供多学科交叉的方法学依据，并为识别城市高温脆弱人群、有针对性地制定气候变化适应性策略提供科学指引。

高温热浪严重威胁人群健康，城市高温灾害健康风险评估和预测逐渐得到重视。然而，已有研究很少考虑热浪期间城市热岛效应和臭氧污染的协同影响，也缺乏针对城市居民承灾体的脆弱性和适应能力评估。本项目分析了杭州的臭氧浓度与局地气象因子和大气环流型之间的关系，建立了杭州市近地面臭氧浓度预报模型；更新发展了新的城市地表特征参数——城市土地利用类型和人为热空间数据集，基于新数据进行了WRF/UCM和WRF/UCM-Chem数值模拟实验，讨论了夏季极端高温-城市热岛效应-臭氧之间的相互作用；深入研究了气温-死亡率之间的暴露-反应定量关系，探讨了气温-死亡率关系的城乡差异；分析了臭氧与气温的联合暴露对人体健康的影响；进行了暴露人口分布的高分辨率、高精度模拟，研究了完善城市高温健康风险评估模型，进行了高温灾害脆弱性和风险制图；利用WRF/UCM-Chem进行了杭州未来夏季气候、大气环境的数值模拟实验。本项目成果可以为我国亟需开展的极端天气事件影响人群健康研究提供多学科交叉的方法学依据，并为识别城市高温脆弱人群、有针对性地制定气候变化适应性策略提供科学指引。