Evaluation of the impact of climate change on the characteristics of drought in Sahel Region of Nigeria: 1971–2060

Abstract

The impact of climate change on the agricultural and water resources sectors cannot be overemphasized since West Africa is prone to drought as a result of high variability in rainfall and temperature. In this study, an assessment on the impact of climate change in the Sahel Region of Nigeria (SRN) on drought was carried out between 1971 and 2060. Gridded temperature and rainfall datasets from Climate Research Unit (CRU) and seven Global Climate Models (GCMs) using regional climate model (RCA-4) under Representative Concentration Pathway (RCP) 8.5 scenario were used. Standardized Precipitation and Evapotranspiration Index (SPEI) and the Standardized Precipitation Index (SPI) at 3- and 12-month time steps were used for drought characterization. The RCA-4 ensemble of the 7 GCMs was able to pattern the seasonal cycle of the maximum and minimum temperatures of SRN well as most of the climatic features were captured as indicated by the CRU observation. Furthermore, the results indicated by the RCA-4 ensemble median of SPEI-3 and SPEI-12 show more drought intensity changes than SPI-3 and SPI-12 as the twenty-first century progresses. An awareness that can help policymakers know the impact climate change may have on the agricultural and hydrological sectors of SRN was created.