Drawing on hydrology, rainfall, and climatic data from the past 25 years, this article investigates the effects of climate change on water resources in the transnational Blue Nile Basin (BNB). The primary focus is on determining the long-term temporal and seasonal changes in the flows of the Blue Nile in Ethiopia at the border to Sudan. This is important because the Blue Nile is the main tributary to the Nile river, the lifeline of both Sudan and Egypt. Therefore, to begin with long-term trends in hydrological time series were detected by means of both parametric and  (CCCMA, CNRM, MRI) were applied in this research, within two future time periods (2046-2064 and 2081-2099) and one scenario (A1B). The Abay Basin was divided into seven sub-basins, six of which were used as inlets to the lowest basin at the border to Sudan. The above-mentioned results show that under current climate change scenarios there is a strong seasonal shift to be expected from the present main rainfall season (June to September) to an earlier onset from January to May with less pronounced peaks but longer duration of the rainfall season. This has direct consequences on the streamflow of the Blue Nile, which is connected to the rainfall season and therefore has direct effects on the people living in the sphere of influence of the Nile River.
V. Roth et al. REF have investigated the effects of climate change on water resources in the transnational Blue Nile Basin (BNB) using water data from the past 25 years.
Effects of climate change on water resources in the upper Blue Nile Basin of Ethiopia