Intraseasonal variation and future projection of atmospheric diffusion conditions conducive to extreme haze formation over eastern China  

中国东部有利于强霾污染形成的大气扩散条件的季节内变化及其未来预估

作　　者：FENG Weiyang WANG Minghuai ZHANG Yang DAI Xianglin LIU Xiaohong XU Yangyang 

机构地区：[1]School of Atmospheric Sciences,Nanjing University,Nanjing,China [2]Joint International Research Laboratory of Atmospheric and Earth System Sciences&Institute for Climate and Global Change Research,Nanjing University,Nanjing,China [3]CMA-NJU Joint Laboratory for Climate Prediction Studies,Institute for Climate and Global Change Research,School of Atmospheric Sciences,Nanjing University,Nanjing,China [4]Department of Atmospheric Sciences,Texas A&M University,Texas,USA

出　　处：《Atmospheric and Oceanic Science Letters》2020年第4期346-355,共10页大气和海洋科学快报（英文版）

基　　金：Minghuai WANG is supported by the National Natural Science Foundation of China[grant numbers 91744208,41925023,41575073,and 41621005];the Ministry of Science and Technology of China[grant numbers 2017YFA0604002 and 2016YFC0200503];Yang ZHANG is supported by the National Natural Science Foundation of China[grant number 41675055];This research was also supported by the Collaborative Innovation Center of Climate Change,Jiangsu Province.

摘　　要：Future projection of diffusion conditions associated with extreme haze events over eastern China is of great importance to government emission regulations and public human health.Here,the diffusion conditions and their changes under future warming scenarios are examined.The relative strength of haze events in the Northern China Plain region increase from 150%during 2006–15 to 190%during 2090–99 under RCP8.5 scenarios,induced by a stronger and longer-lasting anticyclone anomaly in eastern China.The strengthened anticyclone anomaly is mainly induced by increased northern wave train convergence emanating from the Barents–Kara Sea,and the longer duration of the anticyclone anomaly is mainly induced by stronger local feedback that can extract more energy from the basic state to maintain the anticyclone anomaly in eastern China.Aerosol reduction is found to play a dominant role in strengthening the upstream wave train near the Barents–Kara Sea and the downstream anticyclone in eastern China,while the effects from increased greenhouse gases are small.The results of this study indicate that future aerosol emissions reduction can induce deteriorating diffusion conditions,suggesting more stringent regulations on aerosol emissions in China are needed to meet air quality standards.有利于强霾污染形成的大气扩散条件的未来预估对政府制定污染减排政策和公共健康具有重要意义。本文利用气候模式集合试验研究了有利于强霾污染形成的大气扩散条件在RCP8.5排放情景下的变化及其与气溶胶减排和温室气体增加的关系。研究结果发现华北平原污染事件的相对强度在未来情境下会增强,这主要是由更强并且持续时间更长的中国东部反气旋距平所引起的。北方波列辐合的增强引起了反气旋距平强度的增加,加强的局地斜压正反馈使得反气旋从背景流中获得更多的能量从而使其持续时间增加。气溶胶减少引起的气候效应对巴伦支卡拉海附近的波列和中国东部的反气旋变化起主导作用,而温室气体增加对其影响较小。研究结果表明,未来减排会导致扩散条件恶化,这表明中国需要采取更严格的污染减排措施,以达到相应的空气质量标准。

关 键 词：Haze diffusion conditions East Asian winter monsoon anticyclone anomaly RCP8.5 aerosol reduction greenhouse gases 

分 类 号：X513[环境科学与工程—环境工程] X169