Observed and simulated PM2.5 data used to study COVID-19 lockdowns' impacts on urban PM2.5 air quality

This data set includes: (1) the 5-day running mean PM2.5 concentrations in individual years for 22 stations. These data were used in an analysis published in Atmospheric Chemistry and Physics (Yu et al., Assessing COVID-19 lockdowns’ impacts on global urban PM2.5 air quality with observations and modeling, 2025). Original data were obtained from several sources, which is described in the paper. (2) Observed and GEOS-simulated March-April average PM2.5 difference (ug/m3) between 2020 and 2019 (used to generate Figures 10, 15, and S10). (3) Observed and GEOS-simulated March-April average PM2.5 and AOD differences (ug/m3 or %) between 2020 and 2019 (used to generate Figures 13 and 14).本数据集包含以下内容： (1) 22个观测站点各年份的5日滑动平均PM2.5浓度数据。该数据曾用于一项发表于《Atmospheric Chemistry and Physics》的研究分析（Yu等，2025年《Assessing COVID-19 lockdowns’ impacts on global urban PM2.5 air quality with observations and modeling》）。原始数据来源于多个渠道，具体说明详见该论文。 (2) 2020年与2019年3-4月平均PM2.5浓度的观测值与GEOS模拟值之间的差值（单位：微克/立方米），该数据用于绘制图10、图15及补充图S10。 (3) 2020年与2019年3-4月平均PM2.5浓度和气溶胶光学厚度（Aerosol Optical Depth, AOD）的观测值与GEOS模拟值之间的差值（单位：微克/立方米或百分比），该数据用于绘制图13与图14。