Research on the impact of climate change on food security in Africa

Global warming and the rising frequency of extreme climate events pose significant threats to food security. We examine the influence of climate change on food security in Sub-Saharan Africa, with a specific emphasis on four key crops: maize, rice, wheat, and soybeans. We employ a random forest model to estimate spatial and temporal yield trends based on climate variables, land‑use patterns, and irrigation ratios. We also studied the differential impacts of climate change on various crop types, taking into account their physiological characteristics and responses to changing environmental conditions. This prediction is performed under three Shared Socioeconomic Pathways (SSP2‑4.5, SSP3‑7.0, SSP5‑8.5)-using five global climate models (GCMs): BCC-CSM2-MR, CanESM5, IPSL-CM6A-LR, GFDL-ESM4 and MPI-ESM1-2-LR. The findings suggest the following: (1) Maize, a C4 crop, is projected to experience a severe decrease in future harvests, especially under the SSP5-8.5 scenario. The worst declines are forecasted in eastern South Africa and Zambia. (2) Both rice and wheat are C3 crops that experience a "CO₂ fertilization effect," resulting in an increase in yields over time. The SSP5-8.5 scenario primarily focuses on the increase in rice production in West Africa, highlighting this phenomenon. Conversely, significant increases in wheat yield are observed in South Africa and Nigeria. (3) Soybean, a C3 nitrogen-fixing crop, is projected to retain consistent yields overall but with a modest decline in comparison with past norms. The general distribution pattern of soybean yields remains mostly consistent across the SSP scenarios, with the increase in high-yield regions occurring primarily in South Africa.