新冠肺炎疫情期间气象条件和排放变化对PM_(2.5)的影响  

Impacts of Meteorology and Emission Variations on PM_(2.5) Concentration Throughout the Country During the 2020 Epidemic Period

作　　者：逯世泽 史旭荣 薛文博 雷宇 严刚 LU Shi-ze;SHI Xu-rong;XUE Wen-bo;LEI Yu;YAN Gang(School of Environment,Tsinghua University,Beijing 100084,China;Center of Air Modeling and Systems Analysis,Chinese Academy for Environmental Planning,Beijing 100012,China;State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation,Chinese Academy of Environmental Planning,Beijing 100012,China)

机构地区：[1]清华大学环境学院,北京100084 [2]生态环境部环境规划院,空气质量模拟与系统分析中心,北京100012 [3]生态环境部环境规划院,国家环境保护环境规划与政策模拟重点实验室,北京100012

出　　处：《环境科学》2021年第7期3099-3106,共8页Environmental Science

基　　金：国家重点研发计划项目(2016YFC0207502);国家自然科学基金重大研究计划集成项目(91846301)。

摘　　要：本文基于WRF-CMAQ定量分析了2020年1~3月全国337城市气象条件和排放变化对PM_(2.5)浓度的影响.全国气象条件整体转好1.7%,1月转差1.6%,2~3月分别偏有利1.3%和7.9%;全国污染物排放下降使得PM_(2.5)浓度同比下降14.1%,1~3月分别下降4.0%、25.7%和15.0%.武汉第一季度实测PM_(2.5)浓度同比降幅高于全国水平,与其气象条件大幅转好且污染排放降幅较大有关.北京在疫情发生前和严控期PM_(2.5)浓度同比升高,主要为气象转差所致;复工复产期同比下降,主要为污染排放大幅下降所致."2+26"城市、汾渭平原和长三角在第一季度PM_(2.5)浓度同比均下降,长三角降幅最大,与其污染排放大幅下降有关;"2+26"城市和汾渭平原在疫情发生前气象条件大幅转差,严控期大幅转好,长三角在复工复产期气象条件最有利;重点区域均为疫情严控期污染排放降幅最高,复工复产期降幅趋缓.This study analyzed the impacts of meteorological conditions and changes in air pollutant emissions on PM_(2.5) across the country during the first quarter of 2020 based on the WRF-CMAQ model. Results showed that the variations in meteorological conditions led to a national PM_(2.5) concentration decreased of 1. 7% from 2020-01 to 2020-03,whereas it increased by 1. 6% in January and decreased by 1. 3% and 7. 9% in February and March,respectively. The reduction of pollutants emissions led to a decrease of14. 1% in national PM_(2.5) concentration during the first quarter of 2020 and a decrease of 4. 0%,25. 7%,and 15. 0% in January,February,and March,respectively. Compared to the same period last year,the PM_(2.5) concentration measured in Wuhan City decreased more than in the entire country. This was caused by improved meteorological conditions and a higher reduction of pollutant emissions in Wuhan City. PM_(2.5) in Beijing increased annually before the epidemic outbreak and during the strict control period,mainly due to unfavorable meteorological conditions. However,the decrease in PM_(2.5) in Beijing compared to March 2019 was closely related to the substantial reduction of emissions. The measured PM_(2.5) in the"2 + 26"cities,the Fenwei Plain and the Yangtze River Delta( YRD)decreased during the first quarter of 2020,with the largest drop occurring in the Yangtze River Delta due to higher YRD emissions reductions. The meteorological conditions of "2 + 26 "cities and Fenwei Plain were unfavorable before the epidemic outbreak and greatly improved during the strict control period,whereas the Yangtze River Delta had the most favorable meteorological conditions in March. The decrease in PM_(2.5) concentration caused by the reduction of pollutant emissions in the three key areas was highest during the strict control period.

关 键 词：新冠肺炎疫情期间 WRF-CMAQ模型 PM_(2.5) 气象定量影响 排放定量影响 

分 类 号：X513[环境科学与工程—环境工程]