Studies have established that extreme air pollution is more prevalent and is responsible for more deaths and disability-adjusted life years (DALY) in urban cities, especially in developing economies. However, the paucity of ground-based observation has greatly hindered extensive and long-term monitoring and, as such, a good understanding of the trend and characteristics of air quality where it matters most. Aerosol optical depth (AOD) from satellites retrievals provides good spatial and temporal resolutions of atmospheric aerosols and could be a good proxy for ground-level PM_2.5 concentration. This study used a Bayesian regression model to determine the parameters of a PM_2.5 model at four monitoring stations using AOD and selected atmospheric variables (PBLH and RH) as input. The dry-air reference value (K) and the integrated humidity coefficient (γ) were used to delineate the effects of the aerosol characteristics. The values of K and γ, $0.02<K<0.07$ (${\mathrm{m}}^2{\mathrm{g}}^{\mathrm{-1}}$) and $0.54<\gamma <3.14$, respectively, are site-specific even within the same country as is the case for Lekki and Benin (both in Nigeria). The PM_2.5 estimates from the developed observation-based model were in good agreement with the ground-based observations ($0.55<r<0.77$). RH and a combination of PBLH-RH were the best performers in the development of the model. Firstly, this study identifies the unique range of values for K and $\gamma$ for site-classes in the sub-Saharan tropical climate. Secondly, PBLH adds more explanatory power to the PM_2.5 estimates in Benin and Douala (both non-coastal cities) while RH improves the performance of the model significantly in Lekki and Owendo (both coastal cities). For West Africa and similar data-sparse regions, the methodology presented here offers a practical pathway to enhance air quality monitoring capabilities.

Collaboration on Capacity Development in Climate Change Impacts and Adaptation in Africa could provide a beneficial engagement between Europe and Africa. Knowledge exchange could facilitate the transfer of knowledge, technology, and expertise in climate change impact assessment and adaptation strategies while capacity Building will strengthen local skills and institutional frameworks in Africa to address climate-related challenges effectively. A joint research and innovation initiative between Europe and Africa can promote collaborative research projects focused on sustainable solutions tailored to African contexts. Finally, policy alignment between the two regions will align efforts with global frameworks such as the Paris Agreement and Agenda 2063. This paper outlines the key objectives of such a collaboration and key focus areas for strengthening the collaboration and concludes with the implementation steps that will be required.

Breathing is life and the quality of air we breathe is important for good quality of living. At the Bayero University in Kano, Nigeria, the Space Weather and Atmospheric Physics Laboratory has collaborated with the Center for Atmospheric Research to establish a network of air quality monitoring and data gathering techniques through setthing up monitoring stations and recently collaborating with the Alliance for education, Science, Engineering and Design in Africa (AESEDA), using low cost air quality monitoring devices and combining the ground-based data with sattelite data to give meaningful and useful data for safety. Data of air pollutants measured and how they correlate with increasein respiratory tract infections during the pandemic were studied. We present the activities of air quality monitoring during the period of 2020; the hieght of the pandemic and the period thereafter. Findings show that there is a need to be concerned as readings of impact of air pollutants are high and most times hiher than the minimum EPA standards.

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.