2015年冬季南京一次污染过程个例分析

城市大气污染在本地排放源稳定的前提下,不仅和局地气象要素相关,还与污染物输送有密切联系。利用大气污染物浓度资料、ECMWF资料以及2015年1月逐日探空观测和地面资料,通过分析天气形势及大气边界层要素在对污染物浓度的影响；同时利用区域风场相关与HYSPLIT后向轨迹模式模拟分析南京地区的污染物来源。结果表明：中高层形势平稳、地面弱高压场或均压场控制下,相对湿度高以及逆温层是污染物积累的重要条件。南京市污染物的主要源地为长三角地区的局地污染、湖南-湖北-安徽和江西-安徽的远距离输送。

Study of the Formation of Air Pollution in Nanjing during the wintertime 2015

The air pollution in urban areas is not only related to local meteorological factors, but also closely depends on the transport of pollutants when the local emissions are stable. In the present study, in order to investigate the influence of weather conditions and atmospheric boundary layer elements on the concentration of the pollutants, we analyzed the concentrations of the atmospheric pollutants, data provided by ECMWF, and the daily sounding and ground data obtained in the observations conducted in January 2015. Besides, the regional wind field correlation and the backward trajectory model HYSPLIT were also used to analyze the pollutant sources of Nanjing. The results show that when the upper air circulation situation was steady,under a control of high pressure field or in a uniform pressure field, the high relative humidity and the inversion layer are favorable for the accumulation of pollutants. In addition, we also found that the pollution in Nanjing is caused by the local pollution of Yangtze River Delta region, long-range transport of the pollutants from Hunan, Hubei and Anhui, and Jiangxi.