Assessing projected changes in meteorological drought severity and frequency under future climate scenarios: Insights from CMIP5 Models in Eastern Tigray, Northern Ethiopia

The study assessed the frequency and severity of past and future meteorological drought in the Eastern Tigray zone. Global climate model data of Coupled Model Intercomparison Phase 5 (CMIP5), 20 General circulation models (GCM), 2 representative concentration pathways (RCP 4.5 and 8.5), and 2 time series (Mid-term (MT) and End-term (ET)) were used to project the future climate of the study area. Delta scenarios were created from the CMIP5 GCMs, bias corrected and spatially downscaled using the R software. Meteorological drought events were analysed using the Standardized Precipitation Index (SPI) and Standardized Precipitation and Evapotranspiration Index (SPEI). The result shows the presence of predominant moderate drought severity in the study area, and it is expected to increase in frequency under all time segments and emission scenarios based on SPEI-12 and SPI-12, reaching a peak during the end of the century under RCP 8.5. Nevertheless, Kilte Awulaelo and Atsbi Wenberta experienced the highest frequency of severe drought, with Kilte Awulaelo reaching 50% occurrence. Rising atmospheric carbon dioxide (CO₂) concentrations are projected to exacerbate drought frequency and severity in the study area in the future climate. High drought frequency and severity will negatively influence crop production. There is, therefore, a need to adopt climate-smart agriculture for sustainable crop yield production and water harvesting and management.