Evaluation of A Regional Climate Model for the Eastern Nile Basin: Terrestrial and Atmospheric Water Balance

Abstract

The study of water balance is considered here as a way to assess the performance of regional climate models and examine model uncertainty and as an approach to understanding regional hydrology, especially interactions between atmospheric and hydrological processes. We studied the atmospheric and terrestrial water balance over the Eastern Nile Basin (ENB) region using the weather research and forecasting (WRF) model. The model performance in simulating precipitation and surface air temperature is assessed by comparing the model output with the data from the Global Precipitation Climatology Center dataset for precipitation and from the University of Delaware for temperature. The results show that the simulated and observed values correlate well. In terms of water balance, the study region was found to be a sink for moisture, where the atmospheric convergence is negative during most of the time. Most of the precipitation originates from moisture fluxes from outside the domain, and the contribution of local evapotranspiration to precipitation is limited, with small values for the moisture recycling ratios year-round. The atmospheric moisture content does not show significant monthly or annual variation. The results indicate that the terrestrial water storage varies seasonally, with negative fluxes during most of the year, except June, July, and August, when most of the precipitation occurs.

Challenges and prospects of transboundary river water conservation and watershed protection in Ethiopia: The case of the upper Blue Nile

“…1 ). Egypt makes up only 4% of the whole Eastern Nile Basin area, while Sudan, South Sudan, and Ethiopia account for 13%, 61%, and 22% of it, respectively [ 29 ]. The Blue Nile, Baro-Akobo, Atbara, and the main Nile—with the exception of the White Nile—are all included in the eastern portion of the Nile River Basin that it drains.…”

Water Balance Trends along Climatic Variations in the Mediterranean Basin over the Past Decades

“…It is also a principal water-extracting component in the most arid regions, and its accurate quantification along with precipitation is becoming more critical with the growing water scarcity in the basin. Several studies assessed the Mediterranean water budget using ET at various scales with a variety of projections and methodologies, i.e., Med-CORDEX [11], the Weather Research and Forecasting model [12], the bucket with a bottom hole (BBH) model with RCMs SMH-E and SMH-B [13], the LPJ model [14], and the transient model [15]. A few studies used the water budget equations with additional parameters, or the runoff or ET estimation at basin scale, while some modified water balance methods for region-specific studies in order to carry out the water budget explicitly [16][17][18][19][20][21].…”