结合激光雷达观测与模式模拟的雾霾区域传输分析

以一次2015年1月3日至5日发生在中国中东部地区的严重雾霾事件为例,综合地基微脉冲激光雷达观测和WRF-Chem模式模拟的方法,揭示雾霾事件过程中的气溶胶颗粒物的跨区域传输特征。研究表明,徐州站点的激光雷达探测到1～3 km的外来颗粒物输入,在两次输入过程中,对当地总的气溶胶光学厚度贡献分别为43%和69%。WRF-Chem模式能够有效模拟预报PM_(2.5)浓度,但实测浓度为高值的区域出现低估现象。徐州地区在冬季易受来自山东西部、河南东部以及安徽北部的污染物的影响而引发雾霾,该区域需加强协作、联防联控。近年来我国冬季高空的风向具有规律性,且风速在逐年加快,雾霾从华北地区向华东地区的传输可能将变成常态。

Regional Pollutant Transport by Combining MPL Observations and Model Simulations

The method integrating ground-based Micro-Pulse Lidar (MPL) observation and WRF-Chem model simulation was used to analyze a severe haze incident in the central and eastern China from January 3 to January 5, 2015 to reveal the regional transport characteristics of aerosol PM in the haze. The lidar at the Xuzhou site detected particulate matters from 1-3 km away, respectively contributing 43% and 69% local pollution during the two inputs. The WRF-Chem model can effectively simulate the PM2.5 concentration, but the measured concentration tended to be higher than the estimation. Xuzhou was susceptible to haze caused by pollutants from western Shandong, eastern Henan, and northern Anhui, so the cooperation in these regions should be strengthened to achieve joint prevention and control. In recent years, the wind direction of winter in China was regular and the wind speed increased year by year, so the haze transport from North China to East China might become normal.