Potential impact of climate change on peanut yield in Senegal, West Africa

Crop models are useful tools to investigate climate change impacts and suitable adaptations strategies on crops. In order to evaluate the impact of climate change on peanut yield in Senegal, a solution of the SIMPLACE crop modelling framework using the Lintul5 crop model together with a Tc model and FAO-56 based approach to simulate evapotranspiration was used with consideration of Tc versus Ta in driving heat stress with output from four regional climate models (RCMs) and two climate change scenarios (RCP4.5 and RCP8.5). Results from six field experiments at two sites (Bambey and Nioro) in Senegal in the dry seasons of 2014 and 2015 and the rainy season of 2014, were used for calibration and evaluation for two peanut varieties. Our calibration and evaluation exercise revealed that simulation skill was markedly improved when Tc was considered under irrigated, dry season conditions during which time the plants were subject to periodic heat stress. Under future climatic conditions, positive changes of up to 2.4% for RCP4.5 and 8.3% for RCP8.5 for seed yield were found when increasing [CO2] is taken into account for the period 2016–2045 in dry season. While, in rainy season seed yield increased by 11.0% for RCP4.5 and 19.0% for RCP8.5. The effect of climate change on seed yield was negative in the dry season where maximum Ta is often higher than 38 °C compared to the rainy season in particular when Ta is used for simulating heat stress effects. It is concluded that climate change could have limited negative impacts on peanut yield in Senegal due to the effect of elevated [CO2]. However, simulated Tc should be used instead of Ta to accurately account for heat stress impact on peanut especially during the dry season.