Analysis of Aerosol Pollution over North-Western Nigeria

This paper analyzes the optical properties and air mass trajectory of aerosol pollution over North-West (NW) Nigeria. The paper studied the Aerosol Optical Depth (AOD), Angstrom Exponent (AE), Single Scattering Albedo (SSA) and air mass trajectory analysis of aerosols pollution over NW Nigeria from 2018 to 2022. For this purpose, the use of satellite products from Ozone Monitoring Instrument (OMI), the Moderate Resolution Imaging Spectroradiometer (MODIS), and back trajectories of air movements calculated using the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) were employed. AOD values were found to reach peak values (~1 at 500 nm) across the years in the study except in 2020, which, showed a steep decline in AOD values during the period. It is surmised that the decline might have been due to the lock down due to Covid19 when vehicular movement that generate particulate matter and black carbon, construction that generate dust plumes were minimal. Analysis of the optical characteristics of the aerosols studied, supported the observation that the pollution consists of mainly Saharan dust and anthropogenic aerosols with a well-defined seasonal cycle. This assumption was confirmed by HYSPLIT backward trajectories and MODIS images.

Keywords: MODIS, Aerosol Optical Depth, Single Scattering Albedo, Angstrom Exponent, Ozone Monitoring Instrument, HYSPLIT.