Assessment of historical and projected spatiotemporal meteorological drought across climate zones of Wabi Shebele River basin, Ethiopia

Le résumé fourni par la source

This study assesses spatiotemporal drought characteristics and trends in different climate zones of Wabi Shebele basin, Ethiopia. The standardized precipitation index (SPI) and reconnaissance drought index (RDI) were used for baseline (1980–2020) and future (2025–2099) period. Historical climate data and bias-corrected Coupled Model Intercomparison Project (CMIP6) projections under Shared Socio-economic Pathway scenarios (SSP2–4.5 and SSP5–8.5) were used. The Mann-Kendall test and Sen’s slope were used to evaluate drought trend. Arc GIS® 10.8 used to map spatial drought distribution. The combined drought frequency of summer and spring season ranges from 10 to 32.5% during historical and 22–36% in future period across agro climatic zones. The highest historical and projected drought frequency observed in summer season using SPI3 with 21.6% and 20% (SPI3/RDI3) under SSP5–8.5 scenario (2025–2099) in the semi-arid zone. Spring season showed non-significant (P > 0.05) drought increment in all Agro climatic Zones (ACZs) during baseline period and in (2061–2099) under SSP2–4.5 as well as in 2025–2060 under SSP5–8.5. Summer season show non-significant increasing drought trend in (2025–2060) under SSP2–4.5 in all ACZs. Based on temporal drought analysis 1980s, 2000s and 2010s were identified as drought year while 2030s, 2040s 2060s, 2080s and 2090s were projected in future. Normal to moderate drought covered north-eastern parts of the basin whereas severe to extreme drought covered southern of the basin. This finding offer valuable insights for the communities to adopt various climate adaptation and mitigation strategies.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.