Ambient air pollution level in the east African region based on satellite remote sensing of NO2, CO, and Aerosol optical depth

Abstract

This study used ten years (2013-2022) of satellite observations to assess the levels of nitrogen dioxide (NO2), carbon monoxide (CO), and aerosol optical depth (AOD) over Eastern Africa. NO2 vertical column density (VCD) varied between 3.17 × 1014 and 4.70 × 1014 molecules cm-2 with a seasonal variability reaching the peak in December every year. CO mixing ratio oscillated between 95.256 ± 15.480 ppbv and 76.011 ± 5.609 ppbv and demonstrated a bimodal seasonal variability. The level of AOD fluctuated between 0.126 ± 0.070 and 0.250 ± 0.165. Generally, the concentrations of these pollutants are comparable to the global levels, though the AOD increasing trend is an indicator of the deterioration of air quality in the east African region.