Evaluation of Past and Future Climate Trends under CMIP6 Scenarios for the UBNB (Abay), Ethiopia

Abstract

Climate predictions using recent and high-resolution climate models are becoming important for effective decision-making and for designing appropriate climate change adaptation and mitigation strategies. Due to highly variable climate and data scarcity of the upper Blue Nile Basin, previous studies did not detect specific unified trends. This study discusses, the past and future climate projections under CMIP6-SSPs scenarios for the basin. For the models’ validation and selection, reanalysis data were used after comparing with area-averaged ground observational data. Quantile mapping systematic bias correction and Mann–Kendall trend test were applied to evaluate the trends of selected CMIP6 models during the 21st century. Results revealed that, ERA5 for temperature and GPCC for precipitation have best agreement with the basin observational data, MRI-ESM2-0 for temperature and BCC-CSM-2MR for precipitation were selected based on their highest performance. The MRI-ESM2-0 mean annual maximum temperature for the near (long)-term period shows an increase of 1.1 (1.5) °C, 1.3 (2.2) °C, 1.2 (2.8) °C, and 1.5 (3.8) °C under the four SSPs. On the other hand, the BCC-CSM-2MR precipitation projections show slightly (statistically insignificant) increasing trend for the near (long)-term periods by 5.9 (6.1)%, 12.8 (13.7)%, 9.5 (9.1)%, and 17.1(17.7)% under four SSPs scenarios.

Near-term regional climate change in East Africa

“…It is important to use accurate estimates of precipitation to assess the model performance and ultimately provide more reliable climate change projections. However, gridded precipitation datasets have limitations due to quality issues (Alaminie et al 2021), especially in African countries where observational sites are spatially sparse (Sun et al 2018).…”

Evaluation and projection of precipitation in Pakistan using the Coupled Model Intercomparison Project Phase 6 model simulations

“…Therefore, the present study proposed an intensive evaluation and ranking of the CMIP6 GCMs for precipitation simulations in a data scare region like Pakistan. The evaluation of GCMs performance and selection of suitable GCMs for a particular region with different climate variables have been found in many recent studies (Abbasian et al ., 2018; Srivastava et al ., 2020; Alaminie et al ., 2021; Bağçaci et al ., 2021; Guo et al ., 2021; Iqbal et al ., 2021).…”

Crop production in northwestern Ethiopian highlands under changing climate

“…The decadal trend finding suggested that tef and barley yields were growing, whereas wheat and faba bean yields were dropping in Farta district (Figure 12). Climate variable both negative and positive relationships with crop yields reported by many scholars (Abera et al, 2018; Alaminie et al, 2021; Ginbo, 2022; Rettie et al, 2022; Wakjira et al, 2021). The result revealed that there was a nonsignificant negligible negative and weak positive correlation between tef yield with the annual rainfall (−0.229) and minimum temperature (0.348), respectively, in Yilmana Densa district (Table 9).…”