报告题目：The Causes and Effects of Arctic Amplification
报告专家：戴爱国 教授
报告时间：2022年5月17日（星期二）9:00-10:00
会议形式：腾讯会议（会议ID：406-470-358）
主 持 人：徐海明 教授
专家简介：
戴爱国，美国纽约州立大学奥尔巴尼分校（University at Albany, SUNY）特聘教授。1985年南京大学学士毕业，1988年中科院大气所硕士毕业， 1996 美国哥伦比亚大学博士毕业。1997-2012年就职于美国国家大气研究中心（NCAR），2012年至今就职于美国纽约州立大学奥尔巴尼分校大气与环境科学系。多年来从事降水与干旱、区域和全球气候变化、全球水循环、北极气候变化等方面的相关研究，在《Nature》、《Nature Climate Change》、《Nature Communications》、《Science Advances》等国际高水平期刊上发表论文180余篇，在全球气候变化、气候模式诊断与评估、降水与干旱、日变化等研究领域做出了重要贡献。截至2022年5月，论文引用率超过50000次，H 指数为82，入选全世界Top 1%高引用率科学家。曾担任美国气象学会气候变率与变化委员会主席、多个国际著名学术刊物（如《Journal of Climate》、《Journal of Hydrology》）主编或副主编。戴爱国教授多年来与国内学者保持合作，曾接待许多国内访问学者和学生。
报告摘要：
The Arctic region has been warming up more than twice as faster as the global mean in recent decades, and model simulations with increasing greenhouse gases (GHG) also show amplified warming over the Arctic. This Arctic amplification (AA) of GHG-induced warming has long been recognized, but it has received renewed attention during the last 10-15 years partly because it can accelerate Arctic sea-ice melting and reduce the meridional temperature gradient, which is important for atmospheric circulation over the northern mid-high latitudes. Earlier research suggested that the stable Arctic air and positive albedo feedback over the Arctic region are the likely causes of the AA. However, recent studies suggest many other possible causes, including local positive water vapor, cloud, and lapse rate feedbacks, and increased poleward energy transport. Our recent work suggests that winter oceanic heating of the atmosphere over the newly exposed Arctic waters is AA’s main cause, all the local feedbacks need to first melt sea ice in order to contribute to AA, and additional AA would be small after winter Arctic sea ice melts away completely. Many recent studies also suggest that Arctic sea-ice loss and the associated AA could alter midlatitude atmospheric circulation patterns and possibly make our weather more extreme. We show that the reduced meridional temperature gradient would dominate over any wind changes, leading to weaker daily temperature variability over most of the northern mid-high latitudes under increasing GHGs. In particular, the GHG-induced Arctic sea-ice loss and associated Arctic warming would not cause winter cooling over Eurasia that was observed during recent decades. In this talk, I will first present an introduction to the topic, and then discuss the recent research advances on the causes and effects of AA under increasing GHGs, with an emphasis on our own work of the last few years.
本次学术报告采用腾讯会议视频方式，欢迎广大师生踊跃参加！
气象灾害预报预警与评估省部共建协同创新中心
气象灾害教育部重点实验室
大气科学学院
2022年5月12日
相关论文：
Dai, A., D. Luo, M. Song, and J. Liu, 2019: Arctic amplification is caused by sea-ice loss under increasing CO2. Nature Communications, 10, 121.
Dai, A., and M. Song, 2020: Little influence of Arctic amplification on midlatitude climate. Nature Climate Change, 10, 231–237.
Dai, A. and J. Deng, 2021: Arctic amplification weakens the variability of daily temperatures over northern mid-to-high latitudes. J. Climate, 34, 2591–2609.
Deng, J. and A. Dai, 2022: Sea ice-air interactions amplify multidecadal variability in the North Atlantic and Arctic region. Nature Communications, 13, 2100.
Jenkins, M. T., and A. Dai, 2021: The impact of sea-ice loss on Arctic climate feedbacks and their role for Arctic amplification. Geophys. Res. Lett., 48, e2021GL094599.