Spatiotemporal change of climate extremes under the projection of CMIP6 model analysis over Awash Basin, Ethiopia

Currently due to experiencing high heat acceleration rate in Africa, analysis of climate extreme indices under future climate scenarios over Awash Basin, Ethiopia, is crucial. Coupled Model Intercomparison Project (Phase 6) models were selected under socioeconomic pathways (SSPs) at near, mid and far future periods to conduct extreme. As a result, Model CMCC-ESM2 for precipitation performs by 0.98 for R² and 0.99 for NSE. For maximum and minimum temperature model MPI-ESM1-2-LR performs around 0.82 for R², 0.81 for NSE and 0.88 for R², 0.86 for NSE respectively in study area. Scenario SSP5-8.5 in the far future period experiences the highest warm period TXx and TXn around 41–42 ℃ and 24 ℃, respectively. The coldest extremes TNn were found at the upper part of the basin under a scenario of SSP1-2.6 between 6.1 and 7.1 ℃. At the upper part of the basin scenario SPP5-8.5 shows that heavy rainfall (R10) occurred for 62–72 days, whereas extremely heavy rainfall (R20) was found in the far future period an average of 6.7–7.7 days and the highest rainfall Rsum was 1700–1900 mm. Dry days CDD occurred for 96–100 days under scenario of SSP2-4.5 in the far future period of lower Awash Basin and wet days CWD were found in the mid-period of SSP1-2.6, around the upper and middle part of the basin for an average of 120–130 days. Due to such change, 23.08% of probability of drought frequency occurred in the near period under the scenario of SSP2-4.5. The information is highly important for building future initiatives on the basin that are related to climate, health, and other extremes.