江淮地区秋季一次典型污染过程分析

结合2018年10月15—20日国控站点监测数据、气象资料及激光雷达走航观测结果,对江淮地区一次重度污染过程进行了分析。利用拉格朗日粒子扩散模型和拉格朗日混合单粒子轨迹模型定性分析了区域污染来源,分别基于激光雷达和空气站实测数据提出了外来源占比的估算方法,结合嵌套网格空气质量预报模式(NAQPMS)的源解析结果,对比分析了外来源占比。以淮北市为例,结合NAQPMS和单颗粒气溶胶质谱的PM2.5在线源解析结果,对比分析此次污染过程的行业来源。结果表明,本地污染累积时段,主要以燃煤和机动车尾气混合源为主(占比>70%);受北方污染输送时段,机动尾气占比显著升高,从19.4%(16日00:00)升至66.7%(17日11:00),淮北市、蚌埠市、合肥市3个城市污染物外来输送占比分别为52.2%~70.6%、48.8%~58.8%、41.5%~59.0%。

Analysis of a Typical Pollution in Autumn of Yangtze-Huaihe Regions

In this paper, the process of a heavy air pollution in Anhui, which is one province of the Yangtze-Huaihe regions, were analyzed based on measured data in state controlling air quality monitoring sites, meteorological data and lidar on-car observation results. Besides, the regional sources of this pollution were qualitatively analyzed by using the backward trajectories of the lagrangian particle dispersion model and the hybird single particle lagrangian integrated trajectory model. And the proportion of external region sources for each cities were estimated with the use of predicted results by nested air quality prediction modeling system (NAQPMS) and two proposed methods, which were based on lidar observation and measured PM_2.5 mass concentration in air monitoring station respectively. Finally, by taking Huaibei, one of the polluted cities in Anhui, as an example, the chemical components and industry sources were analyzed by comparing the NAQPMS-based and single particle mass spectrometry(SPAMS)-based PM_2.5source apportionment results. The results showed the main sources were the mixed coal-fired and motor vehicle exhausts (accounting for more than 70%) in the local accumulation period; during the pollution transportation period, the proportion of motor vehicle exhaust increased significantly from 19.4% (00:00 on October 16th) to 66.7% (11:00 on October 17th), and the proportions of transported external pollution were 52.2%-70.6% for Huaibei, 48.8%-58.8% for Bengbu, and 41.5%-59.0% for Hefei, respectively.