“…(2) Natural condition indicators, topographic condition data include: Enhanced Vegetation Index (EVI), Digital elevation model (DEM), and Normalized Vegetation Index (NDVI); Meteorological conditions include: relative humidity (RHU), mean pressure (PRS), mean temperature (TEM), gradient Surface Temperature (GST), mean wind speed (WIN–S), wind direction (WIN-D), visibility (VIS), planetary boundary layer height (PBL), dew point temperature (DPT), atmospheric stability etc. [ 7 , 9 , 77 ]. (3) Relevant interfering factors: NO 2 , SO 2 , CO, and O 3 can not only represent the emissions of primary pollutants during the formation of PM 2.5 heavy pollution but also are precursors and oxidants for the transformation of secondary pollutants, so they can be used as auxiliary variables to predict PM 2.5 concentrations [ 7 , 62 ].…”