Mitigating agricultural risk under future climate: assessing maize cycle and yield in Brazil

Climate change directly impacts agricultural production, distribution, and accessibility, thereby affecting global food security. There is an urgent need to increase agricultural production by adapting cropping systems to future environmental conditions to meet the demands of a growing population. This study aimed to analyze climate change impacts on maize, specifically focusing on grain yield, water productivity, and evapotranspiration. Eleven maize climate zones (CZs) across Brazil were identified, and ten Global Circulation Models (GCMs) from the CLIMBra database were used for baseline (1981–2010) and future (2041–2070) periods, considering the emission scenarios SSP2-4.5 and SSP5-8.5, linked to the CERES-Maize crop model to simulate future yield. Simulations considered genetic coefficients (P1 and P5) for the current cycle (CC) and a synthetically corrected cycle (SCC). The study assessed variations in means of key variables, yield limits, and production risks. Higher latitudes are projected to experience increased precipitation, while minimum and maximum temperatures are expected to rise across Brazil, with minimum temperature showing the highest variability. The SSP5-8.5 scenario projects the highest values for climate variables. CC simulations indicate a reduction in the crop cycle, while SCC simulations show an extension of the cycle. Grain yield and water productivity are lower under CC than SCC, with the SSP5-8.5 yielding the highest values. CZs with the greatest productivity losses exhibit higher variability in yield limits. The SCC simulation reduces medium-yield risk relative to the baseline, highlighting its potential as an adaptation strategy.