Hydrological modelling of Ethiopian catchments using limited data

Mekonnen, Muluneh; Wörman, Anders; Dargahi, Bijan; Gebeyehu, Admasu

doi:10.1002/hyp.7470

Cited by 28 publications

(19 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Further, the paper reported that more than 60 % of the observed river discharge falls within the 95 % confidence bounds. Mekonnen et al (2009) developed a generic rainfall-runoff model better suited to Ethiopian catchments. They used a spectrum analysis method to extract the relationships between different temporal scales of available daily rainfall and runoff series that reflect the temporal and spatial scales of 25 discharges in two watersheds in Ethiopia.…”

Section: Model Calibration Parameterization and Validationmentioning

confidence: 99%

Critical review of SWAT applications in the upper Nile basin countries

Griensven

Ndomba

Yalew

et al. 2012

Hydrol. Earth Syst. Sci.

162

View full text Add to dashboard Cite

Abstract. The Soil and Water Assessment Tool (SWAT) isan integrated river basin model that is widely applied within the Nile basin. Up to date, more than 20 peer-reviewed papers describe the use of SWAT for a variety of problems in the upper Nile basin countries, such as erosion modelling, land use and climate change impact modelling and water resources management. The majority of the studies are focused on locations in the tropical highlands in Ethiopia and around Lake Victoria. The popularity of SWAT is attributed to the fact that the tool is freely available and that it is readily applicable through the development of geographic information system (GIS) based interfaces and its easy linkage to sensitivity, calibration and uncertainty analysis tools. The online and free availability of basic GIS data that are required for SWAT made its applicability more straightforward even in data-scarce areas. However, the easy use of SWAT may not always lead to appropriate models which is also a consequence of the quality of the available free databases in these regions. In this paper, we aim at critically reviewing the use of SWAT in the context of the modelling purpose and problem descriptions in the tropical highlands of the Nile basin countries. To evaluate the models that are described in journal papers, a number of criteria are used to evaluate the model set-up, model performances, physical representation of the model parameters, and the correctness of the hydrological model balance. On the basis of performance indicators, the majority of the SWAT models were classified as giving satisfactory to very good results. Nevertheless, the hydrological mass balances as reported in several papers contained losses that might not be justified. Several papers also reported the use of unrealistic parameter values. More worrying is that many papers lack this information. For this reason, most of the reported SWAT models have to be evaluated critically. An important gap is the lack of attention that is given to the vegetation and crop processes. None of the papers reported any adaptation to the crop parameters, or any crop-related output such as leaf area index, biomass or crop yields. A proper simulation of the land cover is important for obtaining correct runoff generation, evapotranspiration and erosion computations. It is also found that a comparison of SWAT applications on the same or similar case study but by different research teams and/or model versions resulted in very different results. It is therefore recommended to find better methods to evaluate the representativeness of the distributed processes and parameters (especially when land use studies are envisaged) or predictions of the future through environmental changes. The main recommendation is that more details on the model set-up, the parameters and outputs should be provided in the journal papers or supplementary materials in order to allow for a more stringent evaluation of these models.

show abstract

Section: Model Calibration Parameterization and Validationmentioning

confidence: 99%

Critical review of SWAT applications in the upper Nile basin countries

Griensven

Ndomba

Yalew

et al. 2012

Hydrol. Earth Syst. Sci.

162

View full text Add to dashboard Cite

show abstract

“…The Soil Water Assessment Tool (SWAT) (Arnold et al, 1998) is a leading model that belongs to this category. A review article by Gassman et al (2007) pointed out the fundamental strength of SWAT model as a comprehensive package of hydrological and hydraulic processes that allowed its widespread use in the simulation runoff and water yield (Anand et al, 2007;Mekonnen et al, 2009) and soil water content (Deliberty and Legates, 2003;Mapfumo et al, 2004;Narasimhan et al, 2005), the evaluation of the effect of agricultural and structural BMPs on water quality (Stewart et al, 2006;Gollamudi et al, 2007;Gitau et al, 2008) and the assessment of the effectiveness of structural BMPs on reducing soil erosion (Bracmort et al, 2006;Yang et al, 2009). Gassman et al (2007) recognized that SWAT's strength also reflects its weakness in the sense that empirical and semiempirical depictions of some processes may be overly simplified and require further refinement.…”

Section: Introductionmentioning

confidence: 99%

Two-Way Calibration-Validation of SWAT Model for a Small Prairie Watershed with Short Observed Record

Rahbeh

Chanasyk

Miller

2011

Canadian Water Resources Journal / Revue canadienne des ressour

View full text Add to dashboard Cite

The Soil Water Assessment Tool (SWAT) model was calibrated for a small watershed with extensive irrigation, low runoff, and a short (2004)(2005)(2006)(2007) period of record in the semi-arid region of the Canadian prairies. The watershed is located on a segment of a river. The net flow between the upstream (inlet) and downstream (outlet) locations of the reach comprises only a fraction of the streamflow at the outlet. This type of watershed is rarely investigated and generally different from the ''pear shaped'' single outlet watersheds presented in SWAT literature. The objectives of this study were to determine if SWAT could be calibrated and validated on this unique watershed using one-and two-way calibration-validation methods, and to determine the effect of a variable climatic record on calibrated and validated parameters. To study the effect of a variable climatic record on the calibrated parameters for this watershed a two-way calibration verification scheme that involved two scenarios was used. Scenario 1 involved calibration using 2004 (average precipitation) and 2005 (above average precipitation) and validation on 2006 and 2007 (both below average precipitation). For scenario 2, the calibration and validation periods were reversed. A third scenario utilized the period of 2004Á2006 for calibration and reserved the 2007 data for validation. The objective criteria used to evaluate model performance included decomposition of the Root Mean Square Error (RMSE) into systematic and unsystematic error, the Nash-Sutcliffe efficiency coefficient (EF) and the coefficient of determination (R 2 ) as model best fit objective functions. The calibration results were satisfactory for scenarios 1 and 3. The calibration of scenario 2 and the validation results for all three scenarios were unsatisfactory. The objective criteria calculated separately for each year in the calibration records showed the calibration results were satisfactory for 2005 only, which is the only wet year in the observed record with above average precipitation. Thus, calibrated parameters were mainly influenced by the 2005 wet season. Therefore, SWAT model calibration on a mixed record of wet and dry conditions will reflect the hydrological processes dominant during wet conditions rather than those observed during dry ones.

show abstract

“…It is a freely available public domain model and has been validated for different catchments in different parts of the world (Pikounis et al 2003;Jayakrishnan et al 2005;Ahl et al 2008). However, there are only few applications of the SWAT model to Ethiopian conditions (Tadele and Foerch 2007;Mekonnen et al 2009;Setegn et al 2009aTessema et al 2014). Few water-related research studies were conducted on the upper Awash River basin (Hailemariam 1999;Chekol 2006).…”

Section: Introductionmentioning

confidence: 99%

Sustainability of Integrated Water Resources Management

Setegn¹,

Donoso²

2015

View full text Add to dashboard Cite

Hydrological modelling of Ethiopian catchments using limited data

Cited by 28 publications

References 21 publications

Critical review of SWAT applications in the upper Nile basin countries

Critical review of SWAT applications in the upper Nile basin countries

Two-Way Calibration-Validation of SWAT Model for a Small Prairie Watershed with Short Observed Record

Sustainability of Integrated Water Resources Management

Contact Info

Product

Resources

About