京津冀气溶胶时空变化特征及潜在来源分析

针对京津冀日益恶化的环境问题,采用Terra-MODIS C6.1 MOD04_L2 气溶胶光学厚度(AOD)产品对京津冀地区2011-2020年AOD时空变化特征进行探究,基于 HYSPLIT模型得到京津冀地区3个主要城市的四季主要气流输送轨迹,并结合空气质量指数(AQI)数据和潜在源贡献因子法(PSCF)分析石家庄市不同季节的污染物潜在源区。结果表明：京津冀地区多年AOD空间分布大体呈东南高西北低的特征;10a间AOD总体呈“w型”下降,峰值和谷值出现在2011年(0.49)和2017年(0.33);AOD四季均值由高至低依次为：夏(0.53)>春(0.39)>冬(0.36)>秋(0.32);AOD月变化呈“双峰”型,峰值出现在2月(0.48)和7月(0.59);北京市、天津市和石家庄市四季主要受到短距离气团输送的影响;统计AQI优良率可知京津冀3个主要城市中石家庄市空气质量最差,通过PSCF分析得出影响石家庄市AQI值的潜在源区主要分布在石家庄市本地及周边省市。

Analysis on the Characteristics and Potential Sources of Aerosols in the Beijing-Tianjin-Hebei Region

In response to the deteriorating environmental problems in the Beijing-Tianjin-Hebei region, Terra-MODIS C6.1 MOD04_L2 aerosol optical thickness (AOD) products are used to explore the characteristics of the AOD spatiotemporal changes in the Beijing-Tianjin-Hebei region from 2011 to 2020, based on the HYSPLIT model analyze the transmission paths of pollutants in the Beijing-Tianjin-Hebei four seasons, and in conjunction with the Air Quality Index (AQI) data sources and potential contribution factor method (PSCF) analyze the potential source of contaminants in different seasons of Shijiazhuang City. The results show that: The spatial distribution of AOD in the Beijing-Tianjin-Hebei region for many years is generally high in the southeast and low in the northwest; The AOD in 10 years has a "w-shaped" decline, with peaks and valleys appearing in 2011 (0.49) and 2017 (0.33); The average value of AOD in the four seasons from high to low is: summer (0.53)>spring (0.39)>winter (0.36)>autumn (0.32); Monthly AOD changes are "double peaks", with peaks appearing in February (0.48) and July Month (0.59); The four seasons of Beijing, Tianjin and Shijiazhuang are mainly affected by short-distance air mass transportation; According to statistics of the excellent and good rate of AQI, Shijiazhuang has the worst air quality among the three major cities in Beijing-Tianjin-Hebei, and the PSCF analysis shows that the potential source areas that affect the AQI value of Shijiazhuang are mainly located in Shijiazhuang and surrounding provinces and cities.