Impact of Climate Change on Agricultural Productivity and Food Security in Nigeria: A Bioeconomic Modelling Approach

This study develops a bioeconomic model to assess the impact of climate change scenarios on agricultural productivity and food security outcomes in Nigeria over the period 2025 to 2050. Climate change is projected to alter temperature regimes, rainfall patterns, and extreme weather event frequencies across Nigeria's agricultural zones, with significant implications for crop yields and food availability. A rigorous bioeconomic modelling approach enables quantification of these effects under alternative climate and adaptation scenarios. This study integrates IPCC Representative Concentration Pathway climate projections downscaled to Nigeria with crop simulation models for maize, sorghum, cassava, and cowpea, using DSSAT and APSIM simulation platforms calibrated to Nigeria's major agro-ecological zones. A partial equilibrium agricultural sector model is used to translate crop yield changes into food security outcomes at household level. Three climate scenarios and four adaptation packages are compared. Findings reveal that under the RCP 8.5 high-emission scenario, maize yields could decline by 22 to 31 percent by 2050 in northern Nigeria, creating significant food security deterioration for vulnerable households. Adaptation packages combining drought-tolerant varieties, irrigation expansion, and improved crop management recover 60 to 75 percent of projected yield losses. The study contributes an original integrated bioeconomic climate impact model for Nigeria and recommends urgent scaling of drought-tolerant variety distribution and irrigation investment.

Keywords: climate change, agricultural productivity, bioeconomic modelling, food security, Nigeria.