Research Article
Evaluation of the Performance of CORDEX-Africa Regional Climate Models in Simulating Rainfall and Temperature over the Lake Tana Sub-Basin, Ethiopia
Behabtu Gobeze Mengiste*
,
Yingesu Lemma Mengste,
Temesgen Admasu Yazachew,
Abebe Chalew Haile
Issue:
Volume 12, Issue 2, June 2026
Pages:
25-35
Received:
15 June 2026
Accepted:
6 July 2026
Published:
28 July 2026
Abstract: Climate change is increasingly altering hydrological and climatic systems across the globe, with particularly severe consequences in Sub-Saharan Africa, where vulnerability is high and adaptive capacity remains limited. Ethiopia, and especially the Upper Blue Nile (Abay) Basin, is highly sensitive to climate variability because livelihoods, water resources, and agricultural production depend heavily on rainfall and temperature conditions. In this context, understanding the ability of climate models to simulate local climatic conditions is essential for generating reliable future climate projections and informing adaptation strategies. This study therefore evaluated the performance of three CORDEX-Africa regional climate models (RCMs) CCCma-CanESM2, MOHC-HadGEM2-ES, and MPI-M-MPI-ESM-LR in simulating rainfall and temperature over the Lake Tana sub-basin, one of the most important hydrological regions in Ethiopia. Observed rainfall and temperature data from four meteorological stations Bahir Dar, Gondar, Debre Tabor, and Dangla were used as reference data for the baseline period 1976-2005. The performance of the selected RCMs was assessed using widely applied statistical indicators, including Percentage Bias (PBIAS), Root Mean Square Error (RMSE), correlation coefficient (R), and coefficient of determination (R2). These metrics enabled the comparison of model outputs with observed climatic records in terms of magnitude, variability, and overall agreement. The evaluation results showed that the MPI-M-MPI-ESM-LR model outperformed the other two models in reproducing rainfall, maximum temperature, and minimum temperature across the study area, indicating its relatively higher suitability for climate impact analysis in the Lake Tana sub-basin. Future climate projections under Representative Concentration Pathways (RCP4.5 and RCP8.5) revealed a clear warming trend across the basin toward the end of the twenty-first century. Maximum temperature is projected to increase by about 3.2-4.4°C under the high-emission scenario (RCP8.5), while minimum temperature may rise even more substantially, by 6.4-7.9°C. In contrast, rainfall projections showed no consistent increasing or decreasing trend, suggesting considerable uncertainty in future precipitation patterns. Overall, the study emphasizes the importance of carefully selecting reliable regional climate models and applying bias correction techniques before using projected climate data for hydrological impact assessments, climate risk management, and long-term adaptation planning in climate-sensitive basins such as Lake Tana.
Abstract: Climate change is increasingly altering hydrological and climatic systems across the globe, with particularly severe consequences in Sub-Saharan Africa, where vulnerability is high and adaptive capacity remains limited. Ethiopia, and especially the Upper Blue Nile (Abay) Basin, is highly sensitive to climate variability because livelihoods, water r...
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Research Article
Wind ROS Wind Load and Climate Analysis of Adama Wereda Oromia Ethiopia
Issue:
Volume 12, Issue 2, June 2026
Pages:
36-42
Received:
21 May 2026
Accepted:
16 June 2026
Published:
11 August 2026
Abstract: Climate change induced irregularities in amount and frequency of extreme temperature and precipitation events are likely to increase across the globe. Climate change has created a new challenge to hamper development process throughout the world. For this analysis meteorological daily rainfall station data in millimetre, maximum temperature and minimum temperature data in degreecentgrade, wind speed in meter per second and direction in degree data including historical period from 2025-1995 G. c was taken form Ethiopian Meteorology Institute for a study area of Adama wereda. Result indictes Climatological rainfall (long-term monthly average) in Adama wereda has raised pic in the month of July and August with amount of above 200 mm (two hundred mm). The average daily temperature reaches from 18°C to 24°C prevailed in Adama wereda of Oromia region Ethiopia. Extreme maximum temperature of Adama wereda was recorded 36.1°C and Extreme minimum temperature of Adama wereda was recorded 3.1°C. Wind Rose diagrams has displays for Adama wereda average wind speed for winter season mostly dominated from 4m/s to 7.5m/s and the wind direction in this season dominated to ENE (East North East) direction of in Adama wereda and Wind Rose diagrams has displays for Adama wereda average wind speed for Summer season mostly dominated from 3m/s to 7m/s and the wind direction in this season dominated to WSW (West South West) and SSW (south south west) direction of in Adama wereda. The wind load analaysis indicates for windward wall is 0.0112 km/m2 and for leeward is - 0.0048km/m2. This analysis of climate pattern and trends will have benefits for decision makers and strategy in the study area.
Abstract: Climate change induced irregularities in amount and frequency of extreme temperature and precipitation events are likely to increase across the globe. Climate change has created a new challenge to hamper development process throughout the world. For this analysis meteorological daily rainfall station data in millimetre, maximum temperature and mini...
Show More