Observation-Constrained Assessment of Aerosol Radiative Forcing and Atmospheric Heating in Representative Climatic Zones of Nigeria: A Systematic Review
Abstract
Uncertainties associated with aerosols continue to represent a major contributor to uncertainty in climate projections over West Africa. Climatic gradient in Nigeria, varying from the dry Sahel zone to the wet Guinea Coast, leads to formation of aerosols through Saharan dust deposition, biomass burning, and human emissions. This PRISMA 2020 systematic review synthesizes peer-reviewed articles published from January 2014 until July 2026 on aerosol radiative forcing and atmospheric heating over climatic zones in Nigeria based on ground observations, satellite retrievals, reanalysis products, and radiative transfer simulations. Out of 312 articles screened through Web of Science, Scopus, and Google Scholar databases, only 18 articles fulfilled the inclusion criteria. Aerosol optical depth reached maximum values in the Harmattan season for all zones, where the highest amount of dust occurred in the Sahel and Sudan savanna. Radiative transfer simulations consistently revealed top-of-atmosphere cooling, surface dimming, and 15–35 W m⁻² atmospheric heating in the dry season. Satellite products, mainly MODIS, usually tended to overestimate aerosol optical depth compared to the Ilorin AERONET station, particularly during the wet season, and reanalysis products (MERRA-2, ERA5) were still largely model-dependent for emissions and aerosol transport. The primary deficiency consists of the almost complete absence of long-term ground observations in any sites except for the one (Ilorin) and the lack of joint evaluations of ground-based, satellite-based, reanalysis, and radiative transfer datasets in a certain time period and location. An observation-driven framework based on a combination of validation of ground observations, satellite, and reanalysis products as well as inputs for radiative transfer is proposed as a way to reduce uncertainties in regional climate analyses in Nigeria.