The global land fAOD dataset (2001–2020) using DLFE-Satellite

The fAOD is a vital proxy for the concentration of anthropogenic aerosols in the atmosphere. Global fAOD can be obtained from point-scale Aerosol Robotic Network (AERONET) measurements, but the spatial coverage is limited. To obtain spatially-continuous global fAODs, we applied the DLFE-Satellite method with Moderate Resolution Imaging Spectroradiometer (MODIS) data, ERA5 climate reanalyses, and AERONET data from 2001 to 2020 as inputs.

For independent validation, we used fAOD retrievals obtained from six Surface Radiation budget network (SURFRAD) sites in the USA. Note that SURFRAD sites are in the vicinity of AERONET sites and were not used to train the model. Data from these sites could thus be used for the independent validation of fAOD estimates. The linear relation between DLFE-Satellite and AERONET retrievals had an R value of 0.93 and RMSE of 0.09 μg/m3 ; for validation with SURFRAD retrievals , R = 0.77 and RMSE = 0.14 μg/m3.