Regional changes in extreme heat events in China under stabilized 1.5 ℃ and 2.0 ℃ global warming

• 来源期刊: 气候变化研究进展（英文版）
• 年，卷（期）: 2020,（3）
• 所属期刊栏目: Special topic on East Asian climate response to 1.5/2 ℃ global warming
• 页码范围: 198-209
• 页数: 12页
• 语种: 英文

摘要

Extreme heat events (EHEs) have a significant impact on the social economy and human health. China is a country with a large population and diverse terrain, and it is necessary to project future extreme heat changes in the sub-regions. This study used a specially designed dataset, the Community Earth System Model (CESM) simulations, namely CESM low-warming, to investigate the EHEs in China under 1.5 ℃ and 2.0 ℃ global warming. The results indicate that the regional mean warming over China will exceed the global average, about 1.63 ℃ and 2.24 ℃ in 1.5 ℃ and 2.0 ℃ warmer futures. Compared to the present-day (1976-2005), the frequency and duration of the EHEs in South China are projected to increase the most among the sub-regions. For example, the frequency of EHEs in South China at 1.5 ℃ and 2.0 ℃ warming will exceed 3 and 3.5 times the present-day level. However, when global warming rises from 1.5 ℃ to 2.0 ℃, the increased impacts relative to the 1.5 ℃ warming level will be the lowest in South China (less than 40％), and the highest increased impacts are projected to appear in Northeast China (53％-84％) and Northwest China (53％-107％). The main reason for this situation is that compared with the 1.5 ℃ scenario, the upper zonal westerly in northern China weakens and the continental high pressure enhances under the 2.0 ℃ scenario. Therefore, limiting global warming at 1.5 ℃ instead of 2.0 ℃ is beneficial for eliminating extreme heat events, especially for Northeast China and Northwest China.