ASSESSMENT OF PRECIPITATION CHANGES USING MULTIPLE GENERAL CIRCULATION MODELS OVER THE GAMBIA

Abstract

ABSTRACT Gambia is the smallest nation on the African mainland, covering 10,690 square kilometers. The natural resources and environment have been heavily affected by changes in climate, such as shifts in temperature and rainfall, which have negatively impacted the growth cycles of crops, their production, and the regrowth of forests. This study uses projected changes in precipitation downscaled statistically from three general circulation models (GCMs): the Max Planck Institute of Meteorology (MPI-ESM), the National Centre for Meteorological Research (CNRM-CM5), and the Canadian Centre for Climate Modelling and Analysis (CanESM5) under two representative concentration pathways (RCP 8.5 and 4.5). The study uses spatial and statistical metrics to determine the impact of climate change on projected precipitation in the study area from 2030 to 2060. The RCP 8.5 scenario forecasts annual precipitation reductions of 35.7%, 32.5%, and 25.6%, whereas the RCP 4.5 projects decreases of 33.4%, 29.2%, and 20.4% for CanEM5, MPI-ESM, and CNRM-CM5 by 2030-2060. Thus, the decline will likely lead to a decline in crop yield by 20.4% and 25.8% under the RCP 4.5 and RCP 8.5 in The Gambia. Attaining food sufficiency and security becomes increasingly complicated and unrealistic. Thus, accelerated strategic climate actions such as the implementation of Climate Smart Agriculture (CSA), which includes integrated irrigation and the adoption of highly drought-resistant crops, need to be implemented by government and other stakeholders.