气候变化与城市化背景下我国关键区域两类热浪事件的变化及机理

Under global climate change and regional urbanization, the frequency and intensity of heatwave (HW) events in China have been increasing during recent decades and are projected to become more frequent and severe in the future. The HW events accompanied by high humidity (i.e., humid heat wave, HHW) exert more harmful influences on human health than those with lower humidity (i.e., dry heat wave, DHW). However, previous investigations mainly focus on DHWs, and the possibly distinct long-term changes, synoptic behavior, and atmospheric controls of HHWs remain unclear. This project aims to unravel the characteristics of these two HW types (i.e., HHW and DHW) in three key regions of China (i.e., Beijing-Tianjin-Hebei, the Yangtze River Delta, and the Pearl River Delta), and their responses to global warming and regional urbanization, by integrating climate diagnostics, climate modeling, remote sensing, GIS, and statistical technologies. This study will examine the spatio-temporal evolution patterns of HHW and DHW events, reveal the contributing factors and physical mechanism of these two HW types, quantify the influences of global warming and regional urbanization on them, and unravel the possible physical processes associated with these influences. This project is expected to enhance our understanding of different HW types across China, so as to provide guidance for enhancing our skill in forecasting the occurrences of HW. This study is also crucial for the planning of mitigative measures to alleviate the impacts of climate change and extreme climate events.

在气候变化和城市化影响下，我国许多地区的高温热浪日益加剧。研究表明，伴随高湿度的高温热浪事件（即高温湿热）往往比低湿度的热浪事件（即高温干热）对人类健康和生态环境的影响更加严重，然而以往研究极少考虑高温湿热这一特定类型热浪事件。本课题将结合气候诊断、气候模拟、遥感与地理信息系统、数理统计等技术，系统研究我国珠江三角洲、长江三角洲和京津冀三个关键区域内高温湿热和高温干热两类热浪事件的变化机理，揭示两类热浪的演变特征、发生原因及其大气环流背景，同时量化两类热浪对气候变化和城市化的响应，并阐释在气候变化背景下区域城市化对两类热浪的影响机制和物理过程。本课题可以有效揭示在气候变化和城市化双重背景下我国关键区域内两类热浪事件的特征和机制，以提高极端事件的机理解释和预测能力。研究成果可以辅助制定减缓气候变化及极端气候影响的区域政策，具有重要的科学意义和实际价值。

高温热浪是全球变暖中最核心指标气温的最突出体现，与人类健康关系极为密切，对人类社会和生态环境的影响极为严重。本项目围绕气候变化与城市化下我国不同类型高温热浪事件如何演变这一关键科学问题，结合气候诊断、气候模拟、遥感与地理信息系统、数理统计等技术，开展了深入研究并取得了一系列创新性科研成果：（1）探明了我国不同地区湿热与干热、日间热与夜间热等不同类型热浪事件的变化规律及成因；（2）深入揭示了我国典型区域内多类热浪事件的不同演变特征、成因及大气环流背景；（3）评估了我国不同区域高温热浪对大尺度自然变率（如厄尔尼诺南方涛动ENSO和太平洋经向模态PMM等）和区域城市化等人类活动的响应；（4）详细阐明了在不同自然和人为因素对我国不同区域热浪的影响机制和作用过程。本项目通过系统揭示气候变化和城市化双重背景下我国关键区域内不同类型热浪事件的特征和机制，提高了我国极端天气事件的机理解释和预测能力，研究成果获得了国内外同行的广泛高度评价，为辅助制定减缓气候变化及极端气候影响的区域政策提供重要科学支撑。本项目多项成果已经发表在GRL、J. Climate、npj CAS、Earth’s Future等国际顶尖期刊，目前已经发表SCI论文30篇（其中包括中科院一区论文18篇），申请软件著作权3项。依托本项目，培养研究生毕业5名，项目负责人获批国家级青年人才计划项目。