Amos Tiereyangn Kabo-Bah

Rapid urbanisation in sub-Saharan Africa outpaces the census and survey systemsused to monitor it. Satellite nighttime lights (NTL) are widely used as a low-cost proxy for urban growth and development, yet their behaviour inside Africancities with unreliable electricity supply remains poorly tested. We combine aharmonised DMSP–VIIRS nighttime-light series (1992–2021), NOAA VIIRSNighttime Lights V2 (2012–2025), daytime built-up products, two populationcensuses and the 2014 and 2022 Ghana Demographic and Health Surveys (DHS)to examine urban expansion and development in Greater Accra on a 1 km grid.Lit urban area, mapped with thresholds calibrated against independent references,grew from 133 km2 in 1992 to 1,270 km2 in 2025, overwhelmingly through edgeexpansion along north-eastern, northern and north-western corridors. Built-uparea from the Global Human Settlement Layer grew only 1.7-fold over 1995–2025, against 6.7-fold for lit area, and radiance of the stable urban core fell 20.9%during the 2015 dumsor load-shedding crisis before recovering. Change in lightstracked district population change between the 2010 and 2021 censuses (Spearmanρ = 0.71), although light levels explained population poorly. Against DHS clusterwealth, machine-learning models explained 77% of variance nationally underspatial cross-validation; within Greater Accra, held out from training, a lights-onlyridge model (R2 = 0.40) matched or outperformed models using eleven additionalgeospatial features, and ranked clusters better than Meta’s Relative Wealth Index(Spearman 0.59 vs 0.49 in 2022). However, lights brightened faster than wealthgrew: the model predicted a 0.29 rise in the Greater Accra asset index between2014 and 2022 against an observed 0.02. Nighttime lights are thus a robust tool forranking places and comparing relative change within African cities, but absolutetrends conflate urban growth, wealth and electricity supply and require recalibrationto each period.

Surface water quality in sub-Saharan Africa is being damaged by artisanal and small-scale gold mining (ASGM) but limited numbers of studies combine long-term data, quantitative health risk models and community exposure data. We examined surface water quality and human health risks in the Asutifi North District of Ghana, a river basin subject to ASGM and agriculture for the last 20 years. Water quality data (2011–2025; >2700 points) from 8 sites were analysed for WQI, Cpk, non-carcinogenic and carcinogenic health risk and using IDW and a community survey (N = 189). Four sites were classed as Unsuitable for Drinking (WQI = 215–348) and dominated by Cd and secondarily As and Pb. Of the 29 parameters monitored 19 fell below WHO/Ghana limits (Cpk < 1.00); 5 sites were in negative Cpk space (indicating a system in structural failure). The hazard index was >10 for young children in high exposure scenarios and even above 5 for 70% treatment efficiency. Total Cancer risk was >10 at every site for adults. Sensitivity analyses show contamination concentration to be the most important parameter and duration of exposure to be irrelevant due to a mathematical cancellation. Long-term, point-source pollution, indicates that remediation is needed at mine discharges rather than at the site level. This analysis provided data for emergency water supply and mine drainage treatment.

In numerous shea producing regions of Ghana, rural women benefit significantly from the gathering, initial processing, and eventual selling of shea-based goods for their cash income. On a global scale, shea butter has emerged as a trendy ingredient in premium beauty products, due to its healing qualities, moving away from its traditional role as a cost-effective replacement for cocoa butter. International development organizations have focused on the shea value chain in Ghana as a component of their efforts to support private sector growth and decrease rural poverty. The shea value chain gives Ghanaian women the ability to take control of their financial, social, and entrepreneurial well-being, provide opportunities to earn money, enhance skills, and have more influence in their families and communities. Shea butter production in Ghana has the capacity to boost the productivity of shea butter enterprises, create employment opportunities for marginalized groups, particularly women, and ultimately support women’s empowerment by reducing poverty. Shea ecological zones contain a diverse range of plants and animals and play a key role in storing carbon. In addition to the ecological significance, the shea parklands and ecological zones hold significance as vital resources and symbols of identity, spirituality, and tradition for Ghanaians, contributing significantly to the nation’s cultural heritage. Shea butter from Ghana is highly desirable in global markets because of its superior chemical composition, derived from quality shea nuts. This means that Ghana can grow its shea industry, which will also increase foreign earnings. Therefore, shea could become the next gold for Ghana. In this regard, nature-based solutions and innovations can be employed to agronomically facilitate the supply of quality shea nuts to the shea industry. In alignment with this vision, a new open-access journal called ”Journal of Nature-based Solutions and Innovations” has been launched. This journal is targeted to inspire and communicate imaginative research and innovations in the intersection of nature, sustainability, and novel technology. It is aimed at targeting global challenges such as depletion of resources, loss of biodiversity, climate variability, and environmental degradation through encouraging and disseminating new perspectives that leverage the power of nature and human creativity to provide informed decisions. We welcome impactful submission of impactful papers. Come explore the intricacies of using nature-based solutions and innovations to solve societal and environmental problems.

Surface water contamination by fecal matter threatens human health due to human and biological processes within a watershed, making socioeconomic development crucial for predicting and improving microbiological water quality. Consequently, climate change alters climatic parameters that affect flow regimes and the movement and fate of microorganisms. This study assessed the fate and transport of microbial Escherichia coli (E. coli) concentrations and their sources in the Tano River Basin in Ghana. Additionally, the study predicted future E. coli concentrations using climate change scenarios from the Intergovernmental Panel on Climate Change (IPCC)’s most recent representative concentration pathways (RCPs) and shared socioeconomic pathways (SSPs). Scenario_1 featured planned urbanization, enhanced manure and wastewater treatment, moderate population, livestock density growth, and climate change. Scenario_2 involved higher population growth, minimal improvements in wastewater management, zero manure treatment, higher livestock population, urbanization, and substantial climate change. Calibration and validation using E. coli data from June 2022 to April 2023 showed good agreement with observed concentrations (R², 0.75 and 0.89; NSE, 0.69 and 0.68; PBIAS, 3.4 and 1.9, respectively). The measured and modeled E. coli concentrations were high, with the highest recording at 2.39 log cfu/100 ml during the rainy season. The study finds that the main causes of E. coli concentrations (44%) are point sources, primarily from human feces and livestock manure, followed by upstream pollution (34%) and non-point sources (22%). Non-point sources became the predominant contributors during periods of maximum discharge due to runoff from land and the dilution of point sources. Again Scenario_1 E. coli dropped to 68% and 97% of reference point levels by the 2050s and 2100s, respectively. E. coli concentrations decrease even more with subsequent treatment, such as tertiary treatment, manure treatment, or both. The scenario analysis demonstrates the potential for E. coli reduction through wastewater and manure treatment, driven by socioeconomic and climate change scenarios.

Climate change leading to Climate extremes in the twenty-first century is more evident in megacities across the world, especially in West Africa. The Greater Accra region is one of the most populated regions in West Africa. As a result, the region has become more susceptible to climate extremes such as floods, heatwaves, and droughts. The study employed the Coupled Model Intercomparison Project 6 models in simulating climate extreme indices under the Shared Socioeconomic Pathway scenarios (SSPs) over West Africa between 1979 and 2059 as exemplified by the Greater Accra region. The study observed a generally weak drought in the historical period and expected to intensify especially under SSP585 in Greater Accra. For instance, continuous dry days (CDD) reveal an increasing trend under the SSPs. Similarly, the overall projected trend of CDD over West Africa reveals an increase signifying a more frequent and longer drought in the future. The flood indices revealed a surge in the intensity and duration of extreme precipitation events under the SSPs in the region. For instance, R99pTOT and Rx5days are expected to significantly increase under the SSPs with intensification under the SSP245, SSP370, and SSP585. A similar trend has been projected across West Africa, especially along the Guinean coast. The study foresees a gradual and intensifying rise in heatwave indices over the Greater Accra region. The warming and cooling indices reveal an increasing and decreasing trend respectively in the historical period as well as under the SSPs particularly within urban centers like Accra and Tema. Most West African countries are projected to observe more frequent warm days and nights with cold nights and days becoming less frequent. Expected effects of future climate extreme indices pose potential threats to the water, food, and energy systems as well as trigger recurrent floods and droughts over Greater Accra. The findings of the study are expected to inform climate policies and the nationally determined contribution of the Paris Agreement as well as address the sustainable development goal 11 (Sustainable cities) and 13 (Climate action) in West Africa.

Land Use/Land Cover (LULC) change is a major global concern and a topic of scientific debate. In West Africa, the key trend among the changes of the past few years is the loss of natural vegetation related to changes in different LULC categories, e.g., water bodies, wetland, and bare soil. However, not all detected changes in these LULC categories are relevant for LULC change management intervention in a resource-constrained continent, as a massive change in the dominant LULC types may be due to errors in the LULC maps. Previous LULC change analysis detected large discrepancies in the existing LULC maps in Africa. Here, we applied an open and synergistic framework to update and improve the existing LULC maps for West Africa at five-year intervals from 1990 to 2020—updating them to a finer spatial resolution of 30 m. Next, we detected spatial–temporal patterns in past and present LULC changes with the intensity analysis framework, focusing on the following periods: 1990–2000, 2000–2010, and 2010–2020. A faster annual rate of overall transition was detected in 1990–2000 and 2010–2020 than in 2000–2010. We observed consistent increases in shrubland and grassland in all of the periods, which confirms the observed re-greening of rangeland in West Africa. By contrast, forestland areas experienced consistent decreases over the entire period, indicating deforestation and degradation. We observed a net loss for cropland in the drought period and net gains in the subsequent periods. The settlement category also gained actively in all periods. Net losses of wetland and bare land categories were also observed in all of the periods. We observed net gains in water bodies in the 1990–2000 period and net losses in the 2010–2020 period. We highlighted the active forestland losses as systematic and issued a clarion call for an intervention. The simultaneous active gross loss and gain intensity of cropland raises food security concerns and should act as an early warning sign to policy makers that the food security of marginal geographic locations is under threat, despite the massive expansion of cropland observed in this study area. Instead of focusing on the dynamics of all the LULC categories that may be irrelevant, the intensity analysis framework was vital in identifying the settlement category relevant for LULC change management intervention in West Africa, as well as a cost-effective LULC change management approach.

Land Use /Land Cover (LULC) change is a major global concern and a topic of scientific debate. In West Africa, the key among the past changes is the loss of natural vegetation related to changes in different Land Use/Land Cover (LULC) categories, e.g., water bodies, wetland and bare soil. However, not all detected changes in these LULC categories are relevant for LULC change management intervention in a resource-constrained continent, as a massive change in the dominant LULC types may be due to errors in the LULC maps. Previous LULC change analysis detected large discrepancies in the existing LULC maps in the Africa continent. Here we applied an open and synergistic framework to update and improve the existing LULC maps at every five years intervals from 1990 to 2020 in West Africa at a finer spatial resolution of 30m. Next, we detected spatial temporal pattern in past and present LULC changes with the intensity analysis framework in the periods of 1990–2000, 2000–2010, and 2010–2020. A faster annual rate of overall transition was detected in 1990–2000 (first period) and 2010–2020 (recent period) than in 2000–2010 (middle). We observed consistent gains in rangeland (shrubland and grassland) in all the periods, which confirms the observed re-greening of rangeland in the West Africa continent. By contrast, forestland areas experienced consistent losses for the entire periods, which indicate deforestation and degradation. As regards cropland, a net loss was observed in the drought period and net gains in the subsequent periods. The settlement category also gained actively in all periods. Net losses of wetland and bare land categories were also observed in all the periods. We observed net gains in water bodies in 1990–2000 and net losses in the last period. We highlighted the active forestland losses as systematic and hence a clarion call for an intervention. The simultaneous active gross loss and gain intensity of cropland raises food security concern and must send an early warning signal to policy makers that the food security of marginal geographic locations is under threat despite the massive expansion of cropland observed in this study area. The intensity analysis framework was vital to identify the settlement category as relevant for LULC change management intervention across time and space in West Africa instead of focusing on dynamics of all the LULC categories that may be irrelevant and hence a cost effective LULC change management approach. Policies to control the expansion of settlements will indirectly regulate the expansion of cropland field because we observed that as settlement encroached on cropland, simultaneously cropland encroached on natural vegetation to meet the food security requirements of the inhabitants.

The northeast region of Côte d’Ivoire, where agriculture is the main economic activity, is potentially vulnerable to extreme climatic conditions. This study aims to make a comprehensive spatio-temporal analysis of trends in extreme indices related to precipitation and temperature for the Zanzan region of Côte d’Ivoire over the period of 1981–2020. The statistical significance of the calculated trends was assessed using the non-parametric Mann–Kendall test, while Sen’s slope estimation was used to define the amount of change. For extreme precipitations, the results showed a decreasing trend in annual total precipitations estimated at 112.37 mm and in daily precipitations intensity indices. Furthermore, the consecutive dry days’ index showed an increasing trend estimated at 18.67 days. Unlike the trends in precipitation extremes, which showed statistically non-significant trends, the trends in temperature extremes were mostly significant over the entire study area. The cold spells indices all show decreasing trends, while the warm spells show increasing trends. Drawing inferences from the results, it becomes clear that the study area may be threatened by food insecurity and water scarcity. The results are aimed to support climate adaptation efforts and policy intervention in the region.