2020—2021年江苏省秋、冬季NO_(2)污染特征

NO_(2)Pollution Characteristics in Autumn and Winter of Jiangsu Province in 2020—2021

基于二氧化氮(NO_(2))地面监测数据,结合对流层观测仪(TROPOMI)卫星观测结果,分析了新型冠状病毒流行期间(2020—2021年)江苏省NO_(2)污染特征,并使用气象-空气质量-源解析(WRF-CAMQ-ISAM)数值模式对NO_(2)进行溯源分析。结果表明:2020和2021年江苏省NO_(2)年均质量浓度均为29μg/m^(3),同比2019年下降了21.6%,但秋、冬季(11—12月)仍然是NO_(2)管控的艰难期。TROPOMI卫星和地面观测结果均表明,NO_(2)质量浓度高值区集中在沿江8市。2021年秋、冬季NO_(2)首要污染物天数超过2019年同期,秋、冬季NO_(2)首要污染物情况仍会出现反弹。气象-空气质量(WRF-CAMQ)数值模式给出的管控效果评估表明,2021年秋、冬季气象和人为因素是共同促进江苏省NO_(2)浓度升高的原因,与2020年相比,其气象和人为因素将2021年NO_(2)质量浓度分别抬升了3.1,0.9μg/m^(3)。沿江8市对NO_(2)浓度人为贡献多为正值,NO_(2)质量浓度变化值介于-0.6~6.7μg/m^(3);苏北5市人为贡献多为负值,NO_(2)质量浓度变化值介于-4.6~1.7μg/m^(3)。行业贡献结果表明,秋、冬季NO_(2)来源主要是道路移动源、工业源、非道路移动源,贡献占比分别为39.2%,33.0%,20.8%,船舶和居民源贡献均为3.5%。

Based on NO_(2)ground monitoring data and combined with the observation results of TROPOMI satellite,the characteristics of NO_(2)pollution in Jiangsu Province during the covid-19 pandemic from^(2)020 to 2021 were analyzed.Using WRF-CMAQ-ISAM system model,the characteristics of NO_(2)were analyzed.The results showed that:The NO_(2)concentration in Jiangsu province was 29μg/m^(3)in 2020 and 2021,showing a significant decrease of 21.6%compared with that in 2014—2019.However,autumn and winter(November-December)are still a difficult period for NO_(2)control.TROPOMI satellite and ground observations showed that high NO_(2)values in autumn and winter were concentrated in 8 cities along the Yangtze River.From November to December 2021,the number of days of NO_(2)primary pollutants exceeded the same period in 2019,which showed that pollution by NO_(2)as the primary pollutant in autumn and winter still rebounding.The WRF-CMAQ model indicated that both meteorological and anthropogenic factors in autumn and winter of 2021 jointly contributed to the increase in NO_(2)concentration across Jiangsu Province.Compared with that in 2020,meteorological and human-related factors have increased the concentration of NO_(2)by 3.1 and 0.9μg/m^(3),respectively.In the 8 cities located along the Yangtze River,the anthropogenic influence on the NO_(2)concentration is predominantly positive,ranging from-0.6 to 6.7μg/m^(3).Conversely,in the 5 cities in northern Jiangsu,the anthropogenic impact is predominantly negative,with contribution values ranging from-4.6 to 1.7μg/m^(3).The contribution results of different industries showed that the NO_(2)sources were mainly road mobile sources,industrial sources and non-road mobile sources,accounting for 39.2%,33.0%and 20.8%respectively,and ships and residential sources accounted for 3.5%.