This research report examines the future climate variability of hydrologic regimes and water resources of the Upper Blue Nile River Basin,and the potential impacts of dam operation policies both in the basin and to downstream countries in the 2050s.This report presents three steps for analysing climate change impacts on hydrology and water resources. The first is the construction of the climate change scenarios using multiple general circulation models (GCMs) to understand the current precipitation and temperature patterns. Due to the limited data availabilityand the scale of the sub-basins, the second step is a runoff simulation by using a simple two-tankhydrologic model . In the final step, climate change impacts on hydrology and water resources are examined using a set of indices.The key results of this study are that:
the climate in most of the Nile Basin is likely to become wetter and warmer in the 2050s
the river low flows may become higher and severe
mid- to long-term droughts are likely to become less frequent throughout the entire basin
the potential future dam operations are unlikely to significantly affect the water availability
Overall the major findings of the study include:
there will be a reduction in severe drought events by 2050s due to increased precipitation based on the standardized precipitation index (SPI) points, which is the indication of improved availability of water for agriculture
results of GCM simulation models on the forecasts of future climate indicates that the water resources of the Nile River Basin may not adversely affected by climate change; however, increase precipitation and associated water resources may help to meet future water needs in the region.
the region is likely to have the future potential to produce hydropower, increase the flow duration, and increase the capacity of water storage without affecting any outflows to the riparian countries until the 2050s.
In summary, the authors emphasize for further comprehensive assessments of the impacts of climate change in the basin on issues such as the environment, water quality, and various socioeconomic attributes.