韩博威,马晓燕.2014—2018年冬季长三角强霾事件及天气形势影响分析[J].环境科学学报,2020,40(7):2333-2345
2014—2018年冬季长三角强霾事件及天气形势影响分析
- Analysis of the severe haze events in the Yangtze River Delta during the winter of 2014-2018 and the impact of the weather situation on severe haze
- 基金项目：国家自然科学基金（No.41675004，41975002）
- 韩博威
- 南京信息工程大学气象灾害教育部重点实验室, 气候与环境变化国际合作联合实验室, 气象灾害预报预警与评估协同创新中心, 中国气象局气溶胶与云降水重点开放实验室, 南京 210044
- 马晓燕
- 南京信息工程大学气象灾害教育部重点实验室, 气候与环境变化国际合作联合实验室, 气象灾害预报预警与评估协同创新中心, 中国气象局气溶胶与云降水重点开放实验室, 南京 210044
- 摘要：利用2014-2018年环保部空气污染监测资料以及同期NCEP/NCAR再分析资料，统计分析了冬季长三角地区强霾污染过程中大尺度环流背景场及气象要素对强霾污染的影响.结果表明：2014-2018年冬季长三角地区共发生5次强霾污染过程，每年冬季的12月和1月是强霾污染事件发生的高频时期.当大气中相对湿度维持在较高的水平并且维持较小的风速时，更有利于污染物的累积从而导致强霾污染事件的发生.雾霾天气的发生发展与大气环流有着密切联系，在强霾污染过程发生初期，污染物大多伴随冷空气由北向南输送至长三角地区，对流层中层500 hPa的大尺度环流形势多以纬向环流为主.严重污染发生时，长三角地区受平直西风气流影响，对流层低层850 hPa等压线较为稀疏，长三角地区受均压场或高压控制频繁，稳定的大气层结使污染物更易在近地层累积，随后大风伴随冷锋过境将污染物快速清洁导致PM2.5浓度迅速降低.
- Abstract：In this paper, air pollution monitoring data from the Ministry of Environmental Protection and the NCEP/NCAR reanalysis during 2014-2018 were used to investigate the impacts of large-scale circulation pattern and the associated meteorological parameters on the strong winter haze pollution events in the Yangtze River Delta. It was found that Yangtze River Delta region experienced five strong haze pollution events during 2014-2018, and most of strong events occurred in December and January. Both the relatively high relative humidity and the small wind speed are conducive to pollutant accumulation and thus lead to the occurrence of strong haze pollution events. The occurrence and development of haze weather are closely related to evolution in atmospheric circulation. At the beginning phase of strong haze pollution events, most pollutants are transported by cold front from north to south to the Yangtze River Delta and the latitudinal winds prevail at mid-troposphere. When severe pollution occurs in the Yangtze River Delta region, circulation pattern is featured with westerly currents and relatively sparse isobar at 850 hPa. The Yangtze River Delta region is usually controlled by a uniform distributed pressure field or a high pressure. Meanwhile, the stable atmospheric stratification favors the pollutant accumulation in the surface and then the cold front induced gale wind can directly blow away the pollutants and thus lead to a rapid decrease in PM2.5 concentration.
