Statistical downscaling of ambient air PM concentrations using AOD from TROPOMI data

The growing public health concerns about ambient air quality such as particulate matter (PM) concentrations suggest the need for a holistic monitoring to guide interventions. However, monitoring stations are spatially sparse and preferentially located in urban communities, and often with missing data problems. The growing interest on the use of satellite-retrieved aerosol optical depth (AOD) for monitoring ambient concentrations for particulate matter is well placed. Unlike ground monitoring stations, satellite data have the advantage of board spatial coverage. Calibrating stellate retrieved AOD through statistical downscaling can essentially provide high spatial and temporal resolution information on ambient PM concentrations. AOD retrieved from MODIS has often been used for calibration. The TROPOspheric Monitoring Instrument (TROPOMI) is the satellite instrument on board the Copernicus Sentinel-5 Precursor satellite presents a higher potential for AOD calibration due to its with higher spatial resolution. But AOD retrieved from TROPOMI is yet to be tested for predicting PM concentrations.