Observations and numerical modeling were used to analyze a coarse particulate matter (PM10 )pollution episode that oc-curred 17-19 March 2014 in Nanjing,and the resulting regional pollutant transport.The analysis showed a significantly positive correlation between the measured PM10 concentrations and the near-surface wind speeds,which contrasted with a negative corre-lation between fine particulate matter (PM2.5 )levels and wind speeds.This reflects the contribution of wind-driven regional air pollutant transport to the formation of high levels of PM10 pollution.The regional averages of surface PM10 pollution during the episode in Nanjing indicated low daytime levels and high nighttime levels,both of which were affected by diurnal changes in the boundary layer height.A major contributing factor to regional PM10 transport was identified by a change in near-surface wind di-rection coupled with backward trajectory modeling (using the HYSPLIT model)over the North China Plain and the northern por-tion of Jiangsu province.The seasonally bare farmland in these regions could be a major source of the particles that were dis-charged in this high-PM10 pollution event.The end of the Nanjing pollution episode was prompted by rainfall on 19 March,indi-cating the effectiveness of precipitation in the removal of PM10 by wet scavenging.%基于观测及模拟个例，分析了2014年3月17—19日南京地区出现的大气粗颗粒物重污染过程及其污染物区域传输特征。结果表明，这次大气粗颗粒物重污染过程中观测的 PM10浓度和近地面风速变化呈现显著的正相关，与重雾霾过程中大气细颗粒物 PM2．5浓度和近地面风速的负相关关系不同，说明强风驱动的污染物区域传输对这次大气粗颗粒物 PM10污染形成贡献；受大气边界层高度昼夜变化的影响，整个污染事件的南京地区平均 PM10地面浓度具有昼低夜高的日变化特征；地面风向观测和 HYSPLIT 模拟分析进一步表明，大气粗颗粒物重污染主要贡献来自途经华北平原和苏北地区的 PM10区域传输，春季裸露农田的土壤扬尘可能是这次大气粗颗粒物重污染物的主要来源；伴随3月19日南京地区降雨，大气粗颗粒物重污染事件结束，表明降雨对大气粗颗粒物起到有效的湿清除作用。
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