Combined impacts of aerosols and urbanization on a highly threatened extreme precipitation event in Beijing,China  

作　　者：Tai-Chen FENG Tian-Gang YUAN Zhi-Yuan HU Tie-Jun XIE Shen LAI Wen-Jie DONG Jian-Ping HUANG 

机构地区：[1]School of Atmospheric Sciences,Key Laboratory of Tropical Atmosphere-Ocean System,Ministry of Education,Sun Yat-sen University,Zhuhai 59082,China [2]Southern Marine Science and Engineering Guangdong Laboratory,Zhuhai 519082,China [3]Earth and Environmental Sciences Programme and Graduation Division of Earth and Atmospheric Sciences,Faculty of Science,The Chinese University of Hong Kong,HongKong,China [4]Beijing Municipal Climate Centre,Bejing 100089,China [5]Climate Centre of Guangxi Zhuang Autonomous Region,Nanning 530022,China [6]Collaborative Innovation Center for Western Ecological Safety,Lanzhou University,Lanzhou 730000,China [7]Key Laboratoryfor Semi-Arid Climate Change of the Ministry of Education,College of Atmospheric Sciences,Lanzhou University,Lanzhou 730000,China

出　　处：《Advances in Climate Change Research》2024年第5期883-893,共11页气候变化研究进展（英文版）

基　　金：supported by the National Natural Science Foundation of China(42405026,42075105 and 42305032);the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(grant no.2019QZKK0602);the Guangdong Basic and Applied Basic Research Foundation(2022A1515010585).

摘　　要：On July 21,2012,a catastrophic precipitation event occurred in Beijing,highlighting the serious threat of extreme precipitation on socio-economic development and human health under climate change.Nevertheless,whether,how and to what extent aerosols and urbanization,as the two main influencing factors of urban extreme precipitation,have affected this highly damaging extreme event remains largely unex-plored.Here,we employed the weather research and forecasting model coupled with chemistry(WRF-Chem)and a single-layer urban canopy model to investigate the influences of urbanization,aerosols and their interactions on this extreme precipitation event.We found that the joint intensification effects of urbanization and aerosols on extreme precipitation events greatly enhance its negative influence on megacities.The results indicate that aerosols are enhanced by increasing cloud droplet numbers,thereby intensifying the feedback between precipitation and latent heating.Consequently,the total precipitation increased by 22.6%,raising the precipitation in the Beijing area increase by at least 50 mm.By stimulating atmospheric instability and strengthening vertical air motion(over 0.25 m s^(-1)),the urban heat island effect considerably in-fluences the temporal and spatial distributions of extreme precipitation events,resulting in an increase in warm cloud precipitation(80%)and a decrease(30%)in frontal precipitation.Consequently,joint intensification effects resulted in more concentrated precipitation in the southwest of Beijing,leading to a substantial increase(more than 40%,~80 mm).This condition may be an important reason for the most severe disasters in the southwest of Beijing.

关 键 词：WRF-Chem Extreme precipitation North China AEROSOLS URBANIZATION 

分 类 号：P426.6[天文地球—大气科学及气象学]