长江三角洲地区高温热浪人群健康风险评价

在全球极端气象、气候事件频发的背景下,获取高分辨的灾害风险信息对于区域防灾减灾决策具有重要的参考价值。而在当前的灾害风险评估中,基于行政单元的人口和社会经济等承灾体信息与栅格水平上的致灾因子普遍存在空间不匹配的现象。本文通过融合多源遥感数据和人口、社会经济统计数据,在利用人居指数对高温人口暴露进行空间化的基础上,获取了250 m分辨率的长江三角洲地区高温热浪人群健康风险空间格局。结果表明,风险等级较高的地区集中在上海、常州、杭州、宁波、无锡、嘉兴、泰州等城市的中心城区,主要是较高的人口暴露度和城市高温共同作用的结果;而大城市近郊以及各规模较小的城区的风险等级次之;相对欠发达地区虽然人口暴露程度较低,但较高的高温危险性和社会经济脆弱性指数使得这些地区的高温人群健康风险也不容忽视。识别高风险地区的风险主导因子对于提高人群高温适应能力以及减轻高温健康风险具有重要意义。

Spatially Explicit Assessment of Heat Health Risks Using Multi-source Data: A Case Study of the Yangtze River Delta Region,China

The increase in the frequency and intensity of extreme heat events (EHEs), potentially associated with climate change in the near future, highlights the importance of heat health risks assessment, which is an important starting point for the reduction of heat-related mortality and sustainable development. However, there is a spatiotemporal mismatch between hazard data (at pixel-level) and exposure data (at census unit level) in heat health risks assessment. Based on multisensor remote sensing data and demographic and socioeconomic statistical data, we used a human settlement index to assess heat exposure. Heat health risks and its driving factors were spatially explicitly assessed and mapped at the 250 m × 250 m pixel-level across the Yangtze River Delta region (YRD). The visual inspection suggests that the high risks areas were mainly distributed in urbanized areas of YRD, including the downtown of Shanghai, Changzhou, Hangzhou, Ningbo, Wuxi, Jiaxing and Taizhou, which was mostly driven by the high human exposure and heat hazard index. In less-urbanized cities and the suburban and rural areas of mega-cities, the heat health risks come second. Even though the human exposure index was low in other less-developed areas, the heat health risks in those areas were high due to the high heat hazard and human vulnerability index. It's of great importance to identify the driving factors of high heat health risks to provide science-based support for adaptation strategies and emergency planning.