Smart Physics Approaches for Climate Change Impact Assessment on Sweetcorn Evapotranspiration and Yield across Nigeria’s Agro-Ecological Zones under Different Climate Scenarios

Abstract

Climate change has emerged as one of the most critical environmental challenges affecting agricultural sustainability, hydrological systems and food security globally. In Nigeria, increasing temperature, rainfall variability and hydro-climatic extremes pose severe threats to rain-fed agricultural systems, particularly cereals production across diverse agro-ecological zones. This study applies smart physics-based approaches involving climate modelling, agro-hydrological simulations, data analysis and advanced environmental modelling tools to evaluate the impacts of climate change on maize evapotranspiration (ET) and yield under Representative Concentration Pathways (RCP2.6 and RCP8.5). Climate projections derived from HadGEM2-ES, NorESM1-M and MPI-ESM-MR models were integrated with the DSSAT CERESmaize model to assess future crop responses across rainforest, savannah and Sahel ecological zones in Nigeria. Results indicate substantial warming under future scenarios, with temperature increases exceeding 7°C under RCP8.5 in the Sahel. Evapotranspiration demand increased significantly across all regions due to intensified atmospheric evaporative demand, while maize yield declined sharply under high emission scenarios. Yield-to-Evapotranspiration efficiency (YPEM) deteriorated substantially, particularly in savannah and Sahel regions, indicating increasing hydro-agricultural stress and declining water-use efficiency. The findings provide scientific evidence for climate adaptation, technological innovation and sustainable agricultural management in Nigeria.