Climate change continues to increase the intensity, frequency and impacts of weather and climate extremes. This work uses bias-adjusted Coupled Model Intercomparison Project Phase six (CMIP6) model datasets to investigate the future changes in temperature extremes over Mediterranean (MED) and Sahara (SAH) regions. The mid- (2041–2070) and far-future (2071–2100) are studied under two Shared Socioeconomic Pathways: SSP2-4.5 and SSP5-8.5 scenarios. Quantile mapping function greatly improved the performance of CMIP6 by reducing the notable biases to match the distribution of observation data, the Climate Prediction Center (CPC). Results show persistent significant warming throughout the 21st century, increasing with the increase in radiative forcing. The MED will record a higher increase in temperature extremes as compared to SAH. The warming is supported by the projected reduction in cold days (TX10p) and cold nights (TN10p), with the reduction in the number of cold nights exceeding cold days. Notably, warm spell duration index (WSDI) and summer days (SU) have a positive trend in both timelines over the entire study area. There is a need to simulate how climate sensitive sectors, such as water and agriculture, are likely to be affected by projected changes under different scenarios for informed decision making in the choice and implementation of adaptation and mitigation effective measures.

This paper investigates seasonal and annual of Near-Surface Temperature (NST) trends of records during the last century (1901 – 2018) over Ghana. . The ability of 24 global climate models (GCMs) from the sixth phase of the Coupled Model Intercomparison Project (CMIP6) to simulate abrupt mean temperature changes in Ghana from 1980 - 2014 was assessed. The trends’ magnitude and abrupt changes were detected using Sen Slope Estimator (SSE) and Sequential Mann-Kendall (SQMK) tests, respectively. Root mean square difference (RMSD), correlation coefficient (CC), and mean bias (B) were used to determine the skillfulness of GCMs in simulating NST relative to Climatic Research Unit (CRU TS4.04) datasets. Ghana’s Southern belt is characterized by low temperatures, averaging 25^oC to 27^oC, whilst the northern belt is characterized by high temperatures (29 – 31 ^oC). The inter-annual variability of temperature over Ghana exhibits an increasing trend. Findings depict a significant increase in both the annual and seasonal temperatures of Tmin and Tmean, with a steady increase in Tmax. Results revealed the rate of increase had been higher in the country’s northern regions (0.5°C) than in the south (0.3 – 0.4 °C) in recent decades. The model performances for the interannual variability of annual and FMAM temperatures are better than their JJAS seasonal performances. The study’s overall model ranking shows that Ghana’s best performing models for annual, FMAM and JJAS seasons are INM-CM5-0, NorCPM1, and KACE-1-0-G, respectively. Observations and comparisons provide useful reference values for a comprehensive assessment of various applications.

Plastic products have resulted in enormous pollution in many ecosystem types and regions worldwide. The problem is particularly prominent within aquatic environments, where multiple anthropogenic sources (i.e., agriculture, urbanisation, industries, illegal dumping) are common, exacerbated by interconnectedness between aquatic and terrestrial environments and management challenges. Regional disparities are also common within macroplastic research, with a scarcity of knowledge in African freshwaters. Here, by considering seven riparian sites across four seasons, we determined the abundance and distribution of macroplastic litter along the South African Crocodile River system and its associated tributaries. Macroplastics were sorted and classified into various polymer groups, functional origins, and physical forms for each site and season. We hypothesised that macroplastic abundances would be substantial, with differences among sites and seasons, related to differences in human activities along the river shores, particularly during the summer months when recreational activities was high. We observed significant differences in macroplastic abundances and variation across sites and seasons, with a high macroplastic abundance during autumn (338), while lower total numbers of macroplastics unexpectedly collected during spring and summer (243–263). High proportional abundances of plastic bags and film across all sites and seasons were observed, as well as high abundances of polypropylene polymers. Our study serves as a baseline for understanding seasonal abundance and distribution variations in plastic litter and their driving factors in subtropical river systems, which may help to inform management policies. The study further contributes to resolving knowledge gaps in underrepresented regions, providing novel insights into plastic pollution sources, accumulation, and impacts linked with unique socio-environmental contexts. Thus, it bridges critical data gaps, informing targeted interventions and global comparative analyses in plastic waste management.

Climate change poses significant global challenges, especially in the West African sub-region, with high temperature and precipitation patterns variability, threatening socio-economic stability and ecosystem health. While global factors such as greenhouse gases and oceanic circulations shape regional climates, this study focuses on the understudied role of local climatic variables in influencing near-surface air temperature (NST) in Ghana from 1981 to 2020. Based on ground observations, our findings reveal significant correlations between land surface temperature (LST) and NST before and after the identified breakpoint year of 2001. Additionally, we observe a reduction in precipitation post-2001. We also identify LST as the primary driver of NST and precipitation changes based on cause-effect analysis of multiple factors. Specifically, higher LST leads to decreased precipitation and increased NST, contributing to the increasing trend of NST over the last two decades. The insights are vital for developing targeted adaptation strategies, including integrated land and water management, sustainable agriculture, and effective interventions, directly supporting the United Nations Sustainable Development Goals (SDG) 13 (Climate Action) and SDG 15 (Life on Land). Moreover, the study provides evidence for promoting climate-smart agriculture to ensure food security (SDG 2). By integrating these findings into climate adaptation frameworks, policymakers and stakeholders can better address the unique challenges posed by climate variability in Ghana, ensuring more resilient and sustainable environmental management.