Climate mitigation and adaptation pathways  

According to the United Nations (n.d.), climate change is the long-term shift in temperatures and weather patterns due to natural changes, such as the sun’s activity and significant volcanic eruptions, or human activities, such as burning fossil fuels like coal, oil, and gas. The effects of and challenges caused by climate change on farmers’ ability to manage mixed farming systems in sub-Saharan Africa are well documented in the literature. However, the synergies among mixed farming systems’ components and farmers’ innovation demands and responses to climate change impacts remain fragmented. Using a case of mixed crop-livestock-tree (MCLT) systems in northern Ghana, this paper examined farmers’ responses, their innovation needs, and how these innovations can be catalyzed to enable more farmers to adopt similar climate change adaptations. Our findings show that climate change impacts mixed farming systems in several domains, with these impacts being more visible in some domains. Significant productivity declines are observed in crops, livestock, and the whole mixed farming system. Productivity declines lead to decreased incomes, food availability, and household food security. Female farmers’ access to production factors, resource management, and market participation is reduced. Farmers make technical, managerial, and business changes in response to climate change impacts. Such changes are dominated by technical changes, including using highyielding, disease-resistant, and early-maturing crop varieties, crop and animal pest and disease management, agricultural water and land management, and wind and bush fire control. Interconnections between the MCLT system components include cross-component investments, additional income generation, animal feeding and healthcare improvement, nutrition exchanges, and family nutrition improvement. These interconnections generate income and cash flow and support food and nutrition security, enabling farmers’ adaptation. Climate-resilient innovation bundles to enable farmers’ adaptation include good agricultural practices, circular farming techniques, irrigation packages, information services, and value-chain linkages. Scaling climate-resilient innovations in northern Ghana and other sub-Saharan African contexts require multiple pathways, including innovation platforms, innovation bundling, multi-actor partnerships, inclusive finance, and multistakeholder dialogues to support farmers’ adaptation to climate change.

Climate change induces high variability in drought patterns and extreme precipitation indices in rainfed cocoa farming, impacting cocoa production. This study evaluated water stress, meteorological and agricultural drought conditions, and critical extreme precipitation indices in the worldapos;s two largest cocoa-producing nations from 1981 to 2022. The results revealed a significant reduction in total annual precipitation (PRCPTOT), in the last three decades, with the greatest decline in the 1991–2000 and 2011–2022 periods. Ghana experienced the most significant reduction up to 15% (200mm/year) in the last decade, attributed to a substantial decrease in wet days number (RR1) up to 25days per year, a reduction in maximum consecutive wet days (CWD) up to 6days per year, and an increase in maximum consecutive dry days (CDD) up to 15days per year. Moreover, there was a notable decline in the Simple Daily Intensity Index (SDII), with reductions of up to 4mm/day in certain areas, contributing to increased drought frequency, severity, and duration. In the most recent decade (2011–2022), particularly during the extremely dry years of 2013 and 2015, cocoa-growing regions in Ghana (GHA) and eastern Cte dapos;Ivoire (CIV) experienced prolonged agricultural drought expressed by soil moisture deficit, typically extending from May to September. Additionally, large portions of central and eastern Ghana, as well as northeastern Cte dapos;Ivoire experienced sustained water stress, with over three consecutive months of total monthly precipitation falling below 100mm, negatively impacting cocoa productivity. The decrease in the yield in the range of 2.5% to 37% was noted in the dry years and the following years, varying according to the country depending on the severity of the drought. Sensitivity analysis highlights cocoa yieldapos;s responsiveness to drought and water stress, particularly in specific years when water stress occurred, such as 1984,1985, 1989, 1995, 1999, 2000, and 2008. Considering the observed trends in precipitation patterns and their impact on cocoa production, it is crucial to acknowledge the inherent uncertainty of future precipitation patterns due to climate change. To address this challenge effectively, our study underscores the importance of identifying and closely monitoring regions currently facing water stress, as determined by precipitation and drought indicators. Over the analysed period (1981–2022), we have noted shifts in the distribution of water-stressed areas, highlighting the dynamic nature of this issue. Consequently, we advocate for a targeted approach to implement cocoa supplementary irrigation in consistently water-stressed regions.

Climate change is projected to notably impact water requirements and crop yield; therefore, it is imperative to quantify climate risk and devise climate-resilient field management practices. This study applied the AquaCrop model to Tulsipur, a sub-metropolitan city located in Western Nepal. The model was calibrated and validated on a field scale, and various scenarios were analysed for baseline (2010–2020) and future (2021–2100) periods to formulate workable management strategies for irrigation and fertilizer applications. Results showed that a deficit irrigation strategy could lead to 81% fewer requirements for irrigation in rice and 24% in wheat at the cost of a minimal (~1%) reduction in yield. Water requirement is projected to decrease and crop yield to increase for both crops for all future scenarios, except wheat water requirement, where water requirement is projected to increase by up to 13% in the future. Rainfed irrigation leads to extremely high variance in crop yields. Deficit irrigation under the nationally recommended fertilizer dose is recommended as a better option to develop climate resiliency in cereal yield in the study area.

This study aimed to assess the impact of urbanization on land use dynamics and its consequences on the local climate of the town of Bingerville for the period from 1990 to 2020. Land cover classification was based on Landsat data for the years 1990, 2000, 2015, and 2020 in order to perform a diachronic analysis of surface conditions. Precipitation and temperature data were used to assess local climate trends. A number of extreme precipitation indices (PRCPTOT, RR1, SDII, CWD, CDD, R95p, and R99p) and temperature indices (TN10p, TN90p, TX10p, TX90p, and WSDI) were calculated. The results show a sharp increase in the built-up area from 1990 to 2020, with 32.11 km² (29.68% per year), compared with forest or crops, i.e., 19.09 km² (0.62% per year), and scrubland or fallow land, i.e., 13.21 km²(1.39% per year). However, extreme precipitation indices such as annual precipitation (PRCPTOT), rainy days (RR1), consecutive rainy days (CWD), and extremely rainy days (R99p) have increased from 2011 to 2020. In addition, buildings are correlated with RR1 and CWD. This could be one of the key factors contributing to the occurrence of flooding in the town of Bingerville, which is probably linked to urbanization. As for extreme temperature indices, most show a statistically insignificant trend, except for cold days (TX10p) and hot days (TX90p), which have a statistically significant trend of 0.004 and 0.018, respectively. This means that there have been changes in these two indices. Consecutive hot days (WSDI) and TX90p increased from 2010 to 2016, and buildings also correlated with these two indices. Consequently, changes in land use could have an influence on local temperature through the urban heat island (UHI) phenomenon. However, uncontrolled urbanization has an impact on the local climate. The town authorities need to be aware of this, and be rigorous in this area, to avoid future disasters in Bingerville.