影响上海PM2.5污染不同源地和路径的数值模拟

对2014~2017年上海出现的PM_2.5中度及以上污染过程的地面形势进行分析，发现上海出现PM_2.5中度及以上污染的地面形势场主要可分为输送型、静稳型和叠加型3种类型，其中输送型是影响上海市PM_2.5中度及以上污染的主要天气形势，占比45.8%.通过选取典型个例，分析了3类污染天气型气象成因和维持机制.并利用WRF驱动FLEXPART模式，结合排放源清单，探讨不同污染天气型下影响上海的主要污染物来源：输送型污染有3条影响上海的主要污染传输通道，分别为东路（东海海面）、中路（江苏沿海）和西路（安徽-苏南），主要时段在污染前1d；静稳型污染影响上海的潜在污染源区集中在上海及周边地区；叠加型污染既存在明显污染输送通道，也有明显的上海及周边潜在污染贡献区域.

Numerical simulations of sources and transport pathways of different PM2.5 pollution types in Shanghai

Synoptic weather patterns during the moderate and severe PM_2.5 pollution processes in Shanghai from 2014 to 2017 were analyzed in the paper. The pollution processes were classified into 3types, i.e., the transport type, the stagnant type and the combined type. The severe PM_2.5 pollution events in Shanghai were mostly dominated by the transport type, accounting for 45.8% of total severe pollution events. The FLEXPART model driven by the WRF model with MEIC emissions was used to investigate the meteorological attribution and maintenance mechanisms of air pollution under each weather pattern in this paper. Specifically, the transport type showed 3main pollution transport pathways affected Shanghai, i.e., the eastern pathway (the East China Sea), the middle pathway (Jiangsu coastal area) and the western pathway (Anhui-southern Jiangsu), which mainly occurred 1d before pollution. The stagnant type showed pollution potential source area in Shanghai and its surrounding regions. The combined type showed both apparent transport pathways and potential source area in and nearby Shanghai.