Your search found 6 records
1 Steenhuis, T. S.; Collick, A. S.; Easton, Z. M.; Leggesse, E. S.; Bayabil, H. K.; White, E. D.; Awulachew, Seleshi Bekele; Adgo, E.; Ahmed, A. A. 2009. Predicting discharge and sediment for the Abay (Blue Nile) with a simple model. Hydrological Processes, 23:3728-3737. [doi: https://doi.org/10.1002/hyp.7513]
Simulation models ; Forecasting ; Erosion ; Sedimentation ; Calibration ; Water balance ; Rainfall-runoff relationships ; River basins ; Climate / Ethiopia / Sudan / Egypt / Abay River / Blue Nile River
(Location: IWMI HQ Call no: e-copy only Record No: H042576)
(0.28 MB)
Models accurately representing the underlying hydrological processes and sediment dynamics in the Nile Basin are necessary for optimum use of water resources. Previous research in the Abay (Blue Nile) has indicated that direct runoff is generated either from saturated areas at the lower portions of the hillslopes or from areas of exposed bedrock. Thus, models that are based on infiltration excess processes are not appropriate. Furthermore, many of these same models are developed for temperate climates and might not be suitable for monsoonal climates with distinct dry periods in the Nile Basin. The objective of this study is to develop simple hydrology and erosion models using saturation excess runoff principles and interflow processes appropriate for a monsoonal climate and a mountainous landscape. We developed a hydrology model using a water balance approach by dividing the landscape into variable saturated areas, exposed rock and hillslopes. Water balance models have been shown to simulate river flows well at intervals of 5 days or longer when the main runoff mechanism is saturation excess. The hydrology model was developed and coupled with an erosion model using available precipitation and potential evaporation data and a minimum of calibration parameters. This model was applied to the Blue Nile. The model predicts direct runoff from saturated areas and impermeable areas (such as bedrock outcrops) and subsurface flow from the remainder of the hillslopes. The ratio of direct runoff to total flow is used to predict the sediment concentration by assuming that only the direct runoff is responsible for the sediment load in the stream. There is reasonable agreement between the model predictions and the 10-day observed discharge and sediment concentration at the gauging station on Blue Nile upstream of Rosaries Dam at the Ethiopia–Sudan border.
2 Engda, T. A.; Bayabil, H. K.; Legesse, E. S.; Ayana, E. K.; Tilahun, S. A.; Collick, A. S.; Easton, Z. M.; Rimmer, A.; Awulachew, Seleshi Bekele; Steenhuis, T. S. 2011. Watershed hydrology of the (semi) humid Ethiopian highlands. In Melesse, A. M. (Ed.). Nile River Basin: hydrology, climate and water use. Dordrecht, Netherlands: Springer. pp.145-162.
Watersheds ; Hydrology ; Highlands ; Rainfall-runoff relationships ; Water table ; Simulation models / Ethiopia
(Location: IWMI HQ Call no: 551.483 G136 MEL Record No: H044027)
(0.35 MB)
3 Dile, Y. T.; Tekleab, S.; Ayana, E. K.; Gebrehiwot, S. G.; Worqlul, A. W.; Bayabil, H. K.; Yimam, Y. T.; Tilahun, S. A.; Daggupati, P.; Karlberg, L.; Srinivasan, R. 2018. Advances in water resources research in the Upper Blue Nile Basin and the way forward: a review. Journal of Hydrology, 560:407-423. [doi: https://doi.org/10.1016/j.jhydrol.2018.03.042]
Water resources ; Research ; Water conservation ; Soil conservation ; Erosion ; Climate change ; Land use ; Catchment areas ; Water balance ; Hydrology ; Models ; Economic development ; Agriculture ; Remote sensing / Ethiopia / Upper Blue Nile Basin
(Location: IWMI HQ Call no: e-copy only Record No: H048798)
https://www.sciencedirect.com/science/article/pii/S0022169418302087/pdfft?md5=fd653f0a22b3bbc8ecfa4c346eb5cfc9&pid=1-s2.0-S0022169418302087-main.pdf
https://vlibrary.iwmi.org/pdf/H048798.pdf
https://vlibrary.iwmi.org/pdf/H048798.pdf
(1.32 MB) (1.32 MB)
The Upper Blue Nile basin is considered as the lifeline for ~250 million people and contributes ~50 Gm3 / year of water to the Nile River. Poor land management practices in the Ethiopian highlands have caused a significant amount of soil erosion, thereby threatening the productivity of the Ethiopian agricultural system, degrading the health of the aquatic ecosystem, and shortening the life of downstream reservoirs. The Upper Blue Nile basin, because of limited research and availability of data, has been considered as the "great unknown." In the recent past, however, more research has been published. Nonetheless, there is no state-of-the-art review that presents research achievements, gaps and future directions. Hence, this paper aims to bridge this gap by reviewing the advances in water resources research in the basin while highlighting research needs and future directions. We report that there have been several research projects that try to understand the biogeochemical processes by collecting information on runoff, groundwater recharge, sediment transport, and tracers. Different types of hydrological models have been applied. Most of the earlier research used simple conceptual and statistical approaches for trend analysis and water balance estimations, mainly using rainfall and evapotranspiration data. More recent research has been using advanced semi-physically/physically based distributed hydrological models using high-resolution temporal and spatial data for diverse applications. We identified several research gaps and provided recommendations to address them. While we have witnessed advances in water resources research in the basin, we also foresee opportunities for further advancement. Incorporating the research findings into policy and practice will significantly benefit the development and transformation agenda of the Ethiopian government.
4 Teshome, F. T.; Bayabil, H. K.; Thakural, L. N.; Welidehanna, F. G. 2020. Modeling stream flow using SWAT [Soil and Water Assessment Tool] model in the Bina River Basin, India. Journal of Water Resource and Protection, 12(3):203-222. [doi: https://doi.org/10.4236/jwarp.2020.123013]
River basins ; Stream flow ; Models ; Calibration ; Water balance ; Land use ; Land cover ; Rainfall-runoff relationships ; Watersheds ; Hydrology ; Uncertainty ; Sensitivity analysis / India / Bina River Basin / Madhya Pradesh
(Location: IWMI HQ Call no: e-copy only Record No: H049695)
(2.58 MB) (2.58 MB)
Understanding watershed runoff processes is critical for planning effective soil and water management practices and efficiently utilize available water resources. The main objective of this study was to investigate the performance of the Soil and Water Assessment Tool (SWAT) to simulate streamflow from the Bina basin in the Madhya Pradesh state of India. The SWAT model was calibrated and validated on a daily and monthly basis using historical streamflow and weather data from the Bina basin. The Sequential Uncertainty Fitting (SUFI-2) technique in the SWAT Calibration and Uncertainty Procedures (SWAT-CUP) program was used to assess model uncertainties. The SWAT model performed “satisfactory” and “very good” in simulating streamflow at daily and monthly time steps, respectively. Model calibration results showed that coefficients of determination (R2) values were 0.66 and 0.96; while Nash-Sutcliffe (NSE) values were 0.65 and 0.94 for daily and monthly simulations, respectively. The R2 values of daily and monthly simulations during model validation were 0.65 and 0.72, respectively while the respective NSE values were 0.58 and 0.72. This study demonstrated that the SWAT model could be effectively used to simulate streamflow in the Bina river basin.
5 Aniley, E.; Gashaw, T.; Abraham, T.; Demessie, S. F.; Bayabil, H. K.; Worqlul, A. W.; van Oel, P. R.; Dile, Y. T.; Chukalla, A. D.; Haileslassie, Amare; Wubaye, G. B. 2023. Evaluating the performances of gridded satellite/reanalysis products in representing the rainfall climatology of Ethiopia. Geocarto International, 38(1):2278329. [doi: https://doi.org/10.1080/10106049.2023.2278329]
Rainfall ; Datasets ; Weather data ; Performance assessment ; Climatology ; Satellite observation ; Agroecological zones ; Precipitation / Ethiopia
(Location: IWMI HQ Call no: e-copy only Record No: H052402)
https://www.tandfonline.com/doi/epdf/10.1080/10106049.2023.2278329?needAccess=true
https://vlibrary.iwmi.org/pdf/H052402.pdf
https://vlibrary.iwmi.org/pdf/H052402.pdf
(3.33 MB) (3.33 MB)
This study evaluated performances of the Climate Hazard Group Infrared Precipitation with stations version 2.0 (CHIRPS v2.0) and Multi-Source Weighted-Ensemble Precipitation version 2.8 (MSWEP v2.8) products against observed data. Rainfall climatology was simulated for different agro-ecological zones (AEZs) of Ethiopia during 1991–2020 at different temporal scales. Performance evaluations were made using continuous and statistical performance measures as well as Probability Density Function (PDF). CHIRPS v2.0 for estimating monthly, seasonal, and annual rainfall totals, and MSWEP v2.8 for daily rainfall have shown better performance over all AEZs. The two products display comparable performance for detecting daily rainfall occurrences over alpine AEZ, but MSWEP v2.8 is superior in the rest four AEZs. CHIRPS v2.0 outperforms MSWEP v2.8 for detecting most of the daily rainfall intensity classes over all AEZs. The findings will play a noteworthy role to improve the quality of hydro-climate studies in Ethiopia.
6 Gashaw, T.; Wubaye, G. B.; Worqlul, A. W.; Dile, Y. T.; Mohammed, J. A.; Birhan, D. A.; Tefera, G. W.; van Oel, P. R.; Haileslassie, Amare; Chukalla, A. D.; Taye, Meron Teferi; Bayabil, H. K.; Zaitchik, B.; Srinivasan, R.; Senamaw, A.; Bantider, A.; Adgo, E.; Seid, Abdulkarim. 2023. Local and regional climate trends and variabilities in Ethiopia: implications for climate change adaptations. Environmental Challenges, 13:100794. [doi: https://doi.org/10.1016/j.envc.2023.100794]
Climate change adaptation ; Climate variability ; Trends ; Strategies ; Rainfall ; Temperature ; Agroecological zones ; Meteorological stations ; Spatial distribution / Ethiopia
(Location: IWMI HQ Call no: e-copy only Record No: H052409)
https://www.sciencedirect.com/science/article/pii/S2667010023001178/pdfft?md5=7a942050dc761a0e0ab04c909ca6637b&pid=1-s2.0-S2667010023001178-main.pdf
https://vlibrary.iwmi.org/pdf/H052409.pdf
https://vlibrary.iwmi.org/pdf/H052409.pdf
(4.10 MB) (4.10 MB)
Ethiopia is experiencing considerable impact of climate change and variability in the last five decades. Analyzing climate trends and variability is essential to develop effective adaptation strategies, particularly for countries vulnerable to climate change. This study analyzed trends and variabilities of climate (rainfall, maximum temperature (Tmax), and minimum temperature (Tmin)) at local and regional scales in Ethiopia. The local analysis was carried out considering each meteorological station, while the regional analyses were based on agroecological zones (AEZs). This study used observations from 47 rainfall and 37 temperature stations obtained from the Ethiopian Meteorological Institute (EMI) for the period of 1986 to 2020. The Modified Mann-Kendall (MMK) trend test and Theil Sen’s slope estimator were used to analyze the trends and magnitudes of change, respectively, in rainfall as well as temperature. The coefficient of variation (CV) and standardized anomaly index (SAI) were also employed to evaluate rainfall and temperature variabilities. The local level analysis revealed that Bega (dry season), Kiremt (main rainy season), and annual rainfall showed increasing trend, albeit no significant, in most stations, but the rainfall in Belg (small rainy) season showed a non-significant decreasing trend. The regional levels analysis also indicated an increasing trend of Bega, Kiremt, and annual rainfall in most AEZs, while Belg rainfall showed a decreasing trend in the greater number of AEZs. The result of both local and regional levels of analysis discerned a spatially and temporally more homogeneous warming trend. Both Tmax and Tmin revealed an increasing trend in annual and seasonal scales at most meteorological stations. Likewise, an increase was recorded for mean Tmax and Tmin in entire/most AEZs. The observed trends and variabilities of rainfall and temperature have several implications for climate change adaptations. For example, the decrease in Belg rainfall in most AEZs would have a negative impact on areas that heavily depend on Belg season’s rainfall for crop production. Some climate adaptation options include identifying short maturing crop varieties, soil moisture conservation, and supplemental irrigation of crops using harvested water during the main rainy season. Conversely, since the first three months of Bega season (October to December) are crop harvest season in most parts of Ethiopia, the increase in Bega rainfall would increase crop harvest loss, and hence, early planting date and identifying short maturing crops during the main rainy season are some climate adaptation strategies. Because of the increase in temperature, water demand for irrigation during Bega season will increase due to increased evapotranspiration. On the other hand, the increase in Kiremt rainfall can be harvested and used for supplemental irrigation during Bega as well as the small rainy season, particularly for early planting. In view of these findings, it is imperative to develop and implement effective climate-smart agricultural strategies specific to each agro-ecological zone (AEZ) to adapt to rainfall and temperature changes and variabilities.
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