Your search found 62 records
1 Haile, Alemseged Tamiru; Kusters, K.; Wagesho, N. 2013. Loss and damage from flooding in the Gambela region, Ethiopia. International Journal of Global Warming, 5(4):483-497. [doi: https://doi.org/10.1504/IJGW.2013.057290]
Flood control ; River basins ; Households ; Livestock ; Income ; Surveys / Ethiopia / Gambela region / Baro River
(Location: IWMI HQ Call no: e-copy only Record No: H046349)
(0.27 MB)
In this article, we explore the ways in which people in the Ethiopian Gambela region dealt with the extreme flood that occurred in 2007, with specific attention to the associated loss and damage, i.e., the impacts that people were not able to avoid through preventive and coping measures. We found that all of the 431 surveyed households took preventive measures such as the construction of boundary walls, harvesting premature crops and digging drainage ditches to divert the flood away from croplands. However, these could not prevent widespread negative effects such as damage to houses and crops, the outbreak of diseases, and loss of livestock. To deal with the adverse effects, 50% of the respondents relied on the help of relatives, neighbours or friends for food and money. Such assistance appeared crucial. People were, however, worried about over-using their social networks, especially with floods occurring more regularly. Widening people's agricultural and non-agricultural options, for example through investments in micro-finance services and irrigation systems, will help to increase their coping capacity.
2 Asres, M. T.; Haile, Alemseged Tamiru; Abebe, Yenenesh. 2014. Opportunities and challenges of a community based rainfall observation network in Meja Watershed of the Upper Blue Nile Basin [Abstract only] In Arba Minch University. A base for building climate resilient green economy: proceedings of the 14th Symposium on Sustainable Water Resources Development, Arba Minch, Ethiopia, 27-28 June 2014. Arba Minch, Ethiopia: Arba Minch University. pp.30-31.
Rainfall patterns ; Measurement ; Watersheds ; River basins / Ethiopia / Jeldu / Upper Blue Nile Basin / Meja Watershed
(Location: IWMI HQ Call no: e-copy only Record No: H046869)
3 Berhanu, Beza; Haile, Alemseged Tamiru. 2014. Evaluating climate change impact on water demand of irrigation schemes in the Lake Tana basin using newly developed climate change scenario [Abstract only] In Arba Minch University. A base for building climate resilient green economy: proceedings of the 14th Symposium on Sustainable Water Resources Development, Arba Minch, Ethiopia, 27-28 June 2014. Arba Minch, Ethiopia: Arba Minch University. pp.29-30.
Climate change ; Water demand ; Irrigation schemes ; Irrigation requirements ; Irrigation water ; River basins / Ethiopia / Lake Tana Basin
(Location: IWMI HQ Call no: e-copy only Record No: H046870)
4 Haile, Alemseged Tamiru; Gebregziabher, Gebrehaweria. 2014. Shallow groundwater irrigation in Dangilaworeda of Amhara region in Ethiopia: situation analysis and area of concern [Abstract only] In Arba Minch University. A base for building climate resilient green economy: proceedings of the 14th Symposium on Sustainable Water Resources Development, Arba Minch, Ethiopia, 27-28 June 2014. Arba Minch, Ethiopia: Arba Minch University. pp.12-13.
Groundwater irrigation ; Wells ; Irrigation water ; Households ; Water demand / Ethiopia / Amhara Region
(Location: IWMI HQ Call no: e-copy only Record No: H046871)
5 Haile, Alemseged Tamiru; Dessalegn, Mengistu; Alemu, E. 2014. Household adaptation to flood in Itang district of Gambela region in Ethiopia. Water - Ethiopian Journal of Water Science and Technology, Special Issue. 3(1):161-167. [Proceedings of the 13th Symposium on Sustainable Water Resources Development, Arba Minch, Ethiopia, 27-28 June 2013]
Households ; Natural disasters ; Climate change ; Adaptation ; Flooding ; Drought ; Food consumption ; Crop production ; Living standards ; Livestock ; Economic aspects / Ethiopia / Gambela Region / Itang
(Location: IWMI HQ Call no: e-copy only Record No: H046872)
6 Habib, E.; Haile, Alemseged Tamiru; Sazib, N.; Zhang, Y.; Rientjes, T. 2014. Effect of bias correction of satellite-rainfall estimates on runoff simulations at the source of the Upper Blue Nile. Remote Sensing, 6(7):6688-6708. [doi: https://doi.org/10.3390/rs6076688]
Rain ; Runoff ; Satellites ; River basins ; Hydrology ; Simulation models ; Calibration ; Catchment areas ; Stream flow / Africa / Ethiopia / Upper Blue Nile Basin
(Location: IWMI HQ Call no: e-copy only Record No: H046873)
(608 KB)
Results of numerous evaluation studies indicated that satellite-rainfall products are contaminated with significant systematic and random errors. Therefore, such products may require refinement and correction before being used for hydrologic applications. In the present study, we explore a rainfall-runoff modeling application using the Climate Prediction Center-MORPHing (CMORPH) satellite rainfall product. The study area is the Gilgel Abbay catchment situated at the source basin of the Upper Blue Nile basin in Ethiopia, Eastern Africa. Rain gauge networks in such area are typically sparse. We examine different bias correction schemes applied locally to the CMORPH product. These schemes vary in the degree to which spatial and temporal variability in the CMORPH bias fields are accounted for. Three schemes are tested: space and time-invariant, time-variant and spatially invariant, and space and time variant. Bias-corrected CMORPH products were used to calibrate and drive the Hydrologiska Byråns Vattenbalansavdelning (HBV) rainfall-runoff model. Applying the space and time-fixed bias correction scheme resulted in slight improvement of the CMORPH-driven runoff simulations, but in some instances caused deterioration. Accounting for temporal variation in the bias reduced the rainfall bias by up to 50%. Additional improvements were observed when both the spatial and temporal variability in the bias was accounted for. The rainfall bias was found to have a pronounced effect on model calibration. The calibrated model parameters changed significantly when using rainfall input from gauges alone, uncorrected, and bias-corrected CMORPH estimates. Changes of up to 81% were obtained for model parameters controlling the stream flow volume.
7 Gumindoga, W.; Rientjes, T.; Shekede, M. D.; Rwasoka, D. T.; Nhapi, I.; Haile, Alemseged Tamiru. 2014. Hydrological impacts of urbanization of two catchments in Harare, Zimbabwe. Remote Sensing, 6(12):12544-12574. [doi: https://doi.org/10.3390/rs61212544]
Hydrological factors ; Urbanization ; Impact assessment ; Catchment areas ; Water management ; Water resources ; Water table ; Land cover change ; Remote sensing ; Satellite imagery ; Rain ; Runoff ; Models ; Woodlands ; Deforestation ; Stream flow ; Soils ; Infiltration / Zimbabwe / Harare / Mukuvisi Catchment / Marimba Catchment
(Location: IWMI HQ Call no: e-copy only Record No: H046874)
(9.22 MB)
By increased rural-urban migration in many African countries, the assessment of changes in catchment hydrologic responses due to urbanization is critical for water resource planning and management. This paper assesses hydrological impacts of urbanization on two medium-sized Zimbabwean catchments (Mukuvisi and Marimba) for which changes in land cover by urbanization were determined through Landsat Thematic Mapper (TM) images for the years 1986, 1994 and 2008. Impact assessments were done through hydrological modeling by a topographically driven rainfall-runoff model (TOPMODEL). A satellite remote sensing based ASTER 30 metre Digital Elevation Model (DEM) was used to compute the Topographic Index distribution, which is a key input to the model. Results of land cover classification indicated that urban areas increased by more than 600 % in the Mukuvisi catchment and by more than 200 % in the Marimba catchment between 1986 and 2008. Woodlands decreased by more than 40% with a greater decrease in Marimba than Mukuvisi catchment. Simulations using TOPMODEL in Marimba and Mukuvisi catchments indicated streamflow increases of 84.8 % and 73.6 %, respectively, from 1980 to 2010. These increases coincided with decreases in woodlands and increases in urban areas for the same period. The use of satellite remote sensing data to observe urbanization trends in semi-arid catchments and to represent catchment land surface characteristics proved to be effective for rainfall-runoff modeling. Findings of this study are of relevance for many African cities, which are experiencing rapid urbanization but often lack planning and design.
8 Haile, Alemseged Tamiru; Yan, F.; Habib, E. 2015. Accuracy of the CMORPH satellite-rainfall product over Lake Tana Basin in eastern Africa. Atmospheric Research, 163:177-187. [doi: https://doi.org/10.1016/j.atmosres.2014.11.011]
Rain ; Satellites ; River basins ; Lakes ; Remote sensing ; Spatial distribution ; Wet season ; Dry season / Eastern Africa / Lake Tana Basin
(Location: IWMI HQ Call no: e-copy only Record No: H046880)
In this study, we assessed the accuracy of rainfall occurrence, amount and distribution over the Lake Tana basin in Ethiopia, Eastern Africa, as represented in the NOAA satellite-based Climate Prediction Center Morphing technique (CMORPH) rainfall product. This analysis is carried out at high spatial and temporal resolutions (8 × 8 km2 and daily) using observations from rain gauges as a reference for the period covering January 2003 to December 2006. Graphical comparisons and several statistical metrics such as bias, correlation coefficient, and standard deviation of rainfall differences are used to perform the evaluation analysis. Spatial maps of these statistical metrics were developed to assess the spatial dependency in the CMORPH accuracy. The bias is decomposed into different components, hit, missed, and false, in order to gain additional insight into the possible sources of systematic deviations in CMORPH. Overall, CMORPH was able to capture the seasonal and spatial patterns of rainfall over the basin, but with varying degrees of accuracy that depend on topography, latitude and lake-versus-land conditions within the basin. The results show that CMORPH captured rain occurrence relatively well in both wet and dry seasons over the southern part of the basin but it significantly overestimated those over the lake and its southern shore. The bias of CMORPH in the study area is characterized by seasonal and spatial variations (-25 to 30% in wet season and -40 to 60% in dry season). False as well as missed rains contribute significantly to the total rainfall amounts over the basin. Significant levels of the differences are observed at the daily resolution of CMORPH. The relation between CMORPH and gauge rainfall amounts is stronger (correlationmostly N0.4) in thewet season than in the dry (mostly b0.4).
9 Fenta, A. A.; Rientjes, T.; Haile, Alemseged Tamiru; Reggiani, P. 2014. Satellite rainfall products and their reliability in the Blue Nile Basin. In Melesse, A. M.; Abtew, W.; Setegn, S. G. (Eds.). Nile river basin: ecohydrological challenges, climate change and hydropolitics. Dordrecht, Netherlands: Springer. pp.51-67.
Satellite observation ; Radar satellite ; Satellite imagery ; Meteorological stations ; River basins ; Rain ; Measurement ; Remote sensing ; GIS ; Precipitation ; Case studies / Ethiopia / Blue Nile Basin
(Location: IWMI HQ Call no: e-copy only Record No: H046898)
(0.37 MB)
In the Upper Blue Nile (UBN) basin, there is very sparse and uneven distribution of ground-based meteorological stations which constrain assessments on rainfall distributions and representation. To assess the diurnal cycle of rainfall across the UBN basin, satellite observations from Tropical Rainfall Measuring Mission (TRMM) were used in this study. Data of 7 years (2002–2008) of Precipitation Radar (PR) and TRMM Microwave Imager (TMI) were processed, with analyses based on geographic information system (GIS) operations, statistical techniques, and harmonic analysis. Diurnal cycle patterns of rainfall occurrence and rain rate from three in-situ weather stations are well represented by the satellite observations. Harmonic analysis depicts large differences in the mean of the diurnal cycle, amplitude, and time of the amplitude across the study area. Diurnal cycle of rainfall occurrence has a single peak in Lake Tana, Gilgel Abbay, and Jemma subbasins and double peaks in Belles, Dabus, and Muger subbasins. Maximum rain rate occurs in the morning (Gilgel Abbay, Dabus, and Jemma), afternoon (Belles, Beshilo, and Muger), and evening (Lake Tana and along the river gorges). Results of this study indicate that satellite observations provide an alternative source of data to characterize diurnal cycle of rainfall in data-scarce regions. We noticed, however, that there are a number of constraints to the use of satellite observations. For more accurate assessments, satellite products require validation by a network of well-distributed ground stations. Also, we advocate bias correction.
10 Akawka, A. L.; Haile, Alemseged Tamiru. 2014. Regionalisation of conceptual rainfall-runoff model parameters for predicting stream flows of ungauged catchments in the Blue Nile Basin [Abstract only] In Eastern Nile Technical Regional Office (ENTRO). Second New Nile Conference on New Nile Opportunities: Scientific Advances Towards Prosperity in the eastern Nile Basin, Addis Ababa, Ethiopia, 8-9 December 2014. Book of abstracts. Addis Ababa, Ethiopia: Eastern Nile Technical Regional Office (ENTRO). pp.29.
River basins ; Catchment areas ; Calibration ; Rain ; Runoff ; Models ; Forecasting ; Hydrology ; Case studies / Ethiopia / Blue Nile Basin
(Location: IWMI HQ Call no: e-copy only Record No: H046924)
(0.06 MB)
Better utilization of water resources depends on the level of understanding of the hydrology of a river basin. The understanding of the hydrology also depends on the extent to which the catchment is gauged. There are many catchments in the Blue Nile basin for which there are very little or no monitoring data available, thus the question as to whether it would be possible to extend and/or generalize model parameters obtained through calibration of gauged watersheds to ungauged catchments within the same region. This study explored the possibility of developing regionalized model parameter sets for use in ungauged catchments. The Blue Nile in the Ethiopian part is sub divided in to 16 sub-basins. In this study, except Dinder and Rahd the remaining 14 sub-basins were considered in the regionalization procedure. The HBV-96 rainfall-runoff model is used to perform the rainfall-runoff analysis. We calibrated HBV model for a number of gauged catchments in the basin. Among the calibrated catchments, 25 catchments were selected for regionalization purpose based on the criteria of relative volume error and Nash Sutcliffe values. For gauged and ungauged catchments, physical catchment characteristics (PCC) were extracted to establish a relationship with the model parameters (MPs) and develop regional model for estimating streamflow for ungauged catchments. The HBV-96 model is used to simulate the runoff from the ungauged catchments. Results from this study indicate that regionalized parameter sets for the HBV model can be obtained and used for making satisfactory hydrologic response predictions in ungauged catchments.
11 Yilak, D. L.; Tilahun, S. A.; Schmitter, Petra; Nakawuka, Prossie; Haile, Alemseged Tamiru; Kassawmar, N. T.; Guzman, C. D.; Steenhuis, T. S. 2015. Adaptation of the SCS [Soil Conservation Service] runoff equation for a (Sub) humid monsoon climate. Paper presented at the 3rd OpenWater Symposium, Addis Ababa, Ethiopia, 16-17 September 2015. 19p.
Climate change ; Monsoon climate ; Humid climate ; Runoff ; Adaptation ; Soil conservation ; Soil moisture ; Watersheds ; Water shortage ; Water balance ; Hydrology ; Models ; Highlands ; River basins ; Rain ; Runoff / Ethiopia / Ethiopian Highland / Maybar Watershed / Anjeni Watershed / Blue Nile Basin
(Location: IWMI HQ Call no: e-copy only Record No: H047279)
(0.01 MB)
The Soil Conservation Service Runoff equation was developed and tested for the temperate climate in the United States. Application to the monsoon climates has been only partially successful. The objective to adapt the SCS equation to a monsoon climate equation is to predict watershed runoff. The adaptation is based on the fact that in many humid areas the main mechanism for direct runoff is saturation excess and in monsoon climates the contributing area expands as a function of the cumulative effective rainfall ( Pe). This then translate in smaller watershed storage (S) in the equation. When estimating runoff contributing area within a watershed and assessing the runoff mechanisms, we have used the original concept of SCS-CN approach in a 113 ha Anjeni and 113ha Maybar Watersheds in the headwaters of the Blue Nile Basin, North Ethiopian highland. Analysis was done at daily, weekly and biweekly base using nine years of hydrological data (1988-97) by classifying the rainfall seasons in to six based on the seasonal cumulative of effective rainfall (Pe). The initial abstraction (Ia) was taken to be equal to the evapotranspiration loss (E) computed by Thornthwaite-Mather water balance method in replacement of the 20% of the potential storage (S). Effective rainfall (Pe) is the difference of total rainfall and Ia. The model performed more as the seasonal cumulative Pe is increased indicating that runoff responses occurred as the watershed saturated. The proportion of runoff contributing area (Af) increased linearly until the cumulative Pe up to nearly 500mm and then the watershed reaches in equilibrium for addition increase of Pe, which is in line with the concept of partial source area hydrology.
12 Haile, Alemseged Tamiru; Tefera, F. T.; Rientjes, T. 2016. Flood forecasting in Niger-Benue basin using satellite and quantitative precipitation forecast data. International Journal of Applied Earth Observation and Geoinformation, 52:475-484. [doi: https://doi.org/10.1016/j.jag.2016.06.021]
Weather forecasting ; Weather data ; River basins ; Precipitation ; Satellite observation ; Flooding ; Rainfall-runoff relationships ; Early warning systems ; International waters ; Tributaries ; Calibration ; Models / Nigeria / Cameroon / Makurdi / Niger River / Benue River / Chadda River / Tchadda
(Location: IWMI HQ Call no: e-copy only Record No: H047675)
Availability of reliable, timely and accurate rainfall data is constraining the establishment of flood forecasting and early warning systems in many parts of Africa. We evaluated the potential of satellite and weather forecast data as input to a parsimonious flood forecasting model to provide information for flood early warning in the central part of Nigeria. We calibrated the HEC-HMS rainfall-runoff model using rainfall data from post real time Tropical Rainfall Measuring Mission (TRMM) Multi satellite Precipitation Analysis product (TMPA). Real time TMPA satellite rainfall estimates and European Centre for MediumRange Weather Forecasts (ECMWF) rainfall products were tested for flood forecasting. The implication of removing the systematic errors of the satellite rainfall estimates (SREs) was explored. Performance of the rainfall-runoff model was assessed using visual inspection of simulated and observed hydrographs and a set of performance indicators. The forecast skill was assessed for 1–6 days lead time using categorical verification statistics such as Probability Of Detection (POD), Frequency Of Hit (FOH) and Frequency Of Miss (FOM). The model performance satisfactorily reproduced the pattern and volume of the observed stream flow hydrograph of Benue River. Overall, our results show that SREs and rainfall forecasts from weather models have great potential to serve as model inputs for real-time flood forecasting in data scarce areas. For these data to receive application in African transboundary basins, we suggest (i) removing their systematic error to further improve flood forecast skill; (ii) improving rainfall forecasts; and (iii) improving data sharing between riparian countries.
13 Cai, Xueliang; Haile, Alemseged Tamiru; Magidi, J.; Mapedza, Everisto; Nhamo, Luxon. 2017. Living with floods – household perception and satellite observations in the Barotse floodplain, Zambia. Physics and Chemistry of the Earth, 100:278-286. [doi: https://doi.org/10.1016/j.pce.2016.10.011]
Natural disasters ; Floodplains ; Hydrology ; Indigenous knowledge ; Remote sensing ; Risk prevention ; Households ; Living standards ; Satellite observation ; Satellite imagery ; Farmland / Zambia / Barotseland
(Location: IWMI HQ Call no: e-copy only Record No: H047877)
The Barotse Floodplain, a designated Ramsar site, is home to thousands of indigenous people along with an extensive wetland ecosystem and food production system. Increasingly it is also a popular tourist destination with its annual Kuomboka festival which celebrates the relocation of the king and the Lozi people to higher ground before the onset of the ood season. This paper presents an integrated approach which cross validates and combines the oodplain residents' perceptions about recent oods with information on ood inundation levels derived from satellite observations. Local residents' surveys were conducted to assess farmers’ perception on the ooding patterns and the impact on their livelihoods. Further, a series of ood inundation maps from 1989 to 2014 generated from remotely sensed Landsat imagery were used to assess the recent patterns of oods. Results show that the oodplain has a population of 33 thousand living in 10,849 small permeant or temporary buildings with a total cropland area of 4976 ha. The oodplain hydrologyand ooding patterns have changed, con rmed by both surveys and satellite image analysis, due to catchment development and changing climate. The average annual inundated areas have increased from about 316 thousand ha in 1989e1998 to 488 thousand ha in 2005 e2014. As a result the inundated cropland and houses increased from 9% to 6% in 1989 to 73% and 47% in 2014, respectively. The timing of the oods has also changed with both delaying and early onset happening more frequently. These changes cause increasing dif culties in ood forecast and preparation using indigenous knowledge, therefore creating greater damages to crops, livestock, and houses. Current oodplain management system is inadequate and new interventions are needed to help manage the oods at a systematic manner.
14 Nigatu, Z. M.; Rientjes, T.; Haile, Alemseged Tamiru. 2016. Hydrological impact assessment of climate change on Lake Tana’s water balance, Ethiopia. American Journal of Climate Change, 5:27-37. [doi: https://doi.org/10.4236/ajcc.2016.51005]
Hydrology ; Impact assessment ; Climate change ; Lakes ; Water balance ; Statistical methods ; Models ; Emission ; Precipitation ; Temperature ; Evaporation ; Catchment areas ; Surface water ; Flow discharge / Ethiopia / Tana Lake
(Location: IWMI HQ Call no: e-copy only Record No: H047947)
The aim of this study is to evaluate the hydrological impacts of climate change on the water balance of Lake Tana in Ethiopia. Impact assessments are by downscaled General Circulation Model (GCM) output and hydrological modeling. For A2 and B2 emission scenarios, precipitation, maximum and minimum temperature estimates from the HadCM3 GCM were used. GCM output was downscaled using the Statistical DownScaling Model (SDSM 4.2). Impact analyses were applied for three future time periods: early, mid and late 21st century. Over-lake evaporation is estimated by Hardgrave’s method, and over-lake precipitation is estimated by inverse distance weighing interpolation, whereas inflows from gauged and ungauged catchments are simulated by the HBV hydrological model. Findings indicate increases in maximum and minimum temperature on annual base for both emission scenarios. The projection of mean annual over lake precipitation for both A2 and B2 emission scenarios shows increasing pattern for 21st century in comparison to the baseline period. The increase of mean annual precipitation for A2 emission scenario is 9% (112 mm/year), 10% (125 mm/year) and 11% (137 mm/year) for the three future periods respectively. B2 emission scenario mean annual precipitation shows increase by 9% (111 mm/year), 10% (122 mm/year) and 10% (130 mm/year) respectively for the three future periods. Findings indicate consistent increases of lake storage for all three future periods for both A2 and B2 emission scenarios.
15 Bhatti, H. A.; Rientjes, T.; Haile, Alemseged Tamiru; Habib, E.; Verhoef, W. 2016. Evaluation of bias correction method for satellite-based rainfall data. Sensors, 16(6):1-16. [doi: https://doi.org/10.3390/s16060884]
Satellite observation ; Rain ; Remote sensing ; Catchment areas ; Runoff water ; Hydrology ; Precipitation ; Meteorology ; Spatial distribution / Ethiopia / Gilgel Abbey Catchment
(Location: IWMI HQ Call no: e-copy only Record No: H047948)
(3.11 MB)
With the advances in remote sensing technology, satellite-based rainfall estimates are gaining attraction in the eld of hydrology, particularly in rainfall-runoff modeling. Since estimates are affected by errors correction is required. In this study, we tested the high resolution National Oceanic and Atmospheric Administration’s (NOAA) Climate Prediction Centre (CPC) morphing technique (CMORPH) satellite rainfall product (CMORPH) in the Gilgel Abbey catchment, Ethiopia. CMORPH data at 8 km-30 min resolution is aggregated to daily to match in-situ observations for the period 2003–2010. Study objectives are to assess bias of the satellite estimates, to identify optimum window size for application of bias correction and to test effectiveness of bias correction. Bias correction factors are calculated for moving window (MW) sizes and for sequential windows (SW’s) of 3, 5, 7, 9, ... , 31 days with the aim to assess error distribution between the in-situ observations and CMORPH estimates. We tested forward, central and backward window (FW, CW and BW) schemes to assess the effect of time integration on accumulated rainfall. Accuracy of cumulative rainfall depth is assessed by Root Mean Squared Error (RMSE). To systematically correct all CMORPH estimates, station based bias factors are spatially interpolated to yield a bias factor map. Reliability of interpolation is assessed by cross validation. The uncorrected CMORPH rainfall images are multiplied by the interpolated bias map to result in bias corrected CMORPH estimates. Findings are evaluated by RMSE, correlation coef cient (r) and standard deviation (SD). Results showed existence of bias in the CMORPH rainfall. It is found that the 7 days SW approach performs best for bias correction of CMORPH rainfall. The outcome of this study showed the ef ciency of our bias correction approach.
16 Haile, Alemseged Tamiru; Akawka, A. L.; Berhanu, B.; Rientjes, T. 2017. Changes in water availability in the Upper Blue Nile basin under the representative concentration pathways scenario. Hydrological Sciences Journal, 62(13):2139-2149.
Water availability ; Water resources ; Climate change ; Temperature ; Drought ; Hydrogeology ; Intensification ; Rainfall-runoff relationships ; Evapotranspiration ; Catchment areas ; Stream flow ; Soil moisture ; Meteorological stations ; Calibration ; Land cover / Ethiopia / Upper Blue Nile Basin
(Location: IWMI HQ Call no: e-copy only Record No: H048259)
http://www.tandfonline.com/doi/pdf/10.1080/02626667.2017.1365149?needAccess=true
https://vlibrary.iwmi.org/pdf/H048259.pdf
https://vlibrary.iwmi.org/pdf/H048259.pdf
limatic and hydrological changes will likely be intensified in the Upper Blue Nile (UBN) basin by the effects of global warming. The extent of such effects for representative concentration pathways (RCP) climate scenarios is unknown. We evaluated projected changes in rainfall and evapotranspiration and related impacts on water availability in the UBN under the RCP4.5 scenario. We used dynamically downscaled outputs from six global circulation models (GCMs) with unprecedented spatial resolution for the UBN. Systematic errors of these outputs were corrected and followed by runoff modelling by the HBV (Hydrologiska ByrånsVattenbalansavdelning) model, which was successfully validated for 17 catchments. Results show that the UBN annual rainfall amount will change by -2.8 to 2.7% with a likely increase in annual potential evapotranspiration (in 2041–2070) for the RCP4.5 scenario. These changes are season dependent and will result in a likely decline in streamflow and an increase in soil moisture deficit in the basin.
17 Nigussie, Likimyelesh; Barron, Jennie; Haile, Alemseged Tamiru; Lefore, Nicole; Gowing, J. 2018. Gender dimensions of community-based groundwater governance in Ethiopia: using citizen science as an entry point. Colombo, Sri Lanka: International Water Management Institute (IWMI). 24p. (IWMI Working Paper 184) [doi: https://doi.org/10.5337/2018.222]
Gender ; Groundwater management ; Groundwater development ; Water governance ; Water security ; Water resources ; Water management ; Water availability ; Water use ; Community involvement ; Citizen participation ; Participatory approaches ; Monitoring ; Role of women ; Women’s participation ; Equity ; Empowerment ; Sustainability ; Decision making ; Natural resources management ; Wells / Ethiopia
(Location: IWMI HQ Call no: IWMI Record No: H048928)
(1 MB)
Understanding the gender dimensions of community-based groundwater governance is important because men and women differ in their need for and having access to groundwater, and their participation in the development, management and monitoring of the resource. The leading role played by women in obtaining and safeguarding water is not usually reflected in the institutional arrangements for water management. Addressing this gender inequality could lead to the equal participation of men and women in monitoring and sustainable management of groundwater, and women’s empowerment. This paper explores gender aspects of community-based groundwater governance in Dangeshta and Farawocha kebeles in Dangila and Boloso Bombe woredas, respectively, in Ethiopia. The findings suggest that women place a high value on groundwater and could be motivated to play a greater role in governance of the resource. However, the constraints they face in participating in groundwater development and management, particularly exclusion from decision-making, suggest that their effective participation and leadership could be significantly curtailed without specific interventions. Indeed, this is reflected in women’s willingness to participate in groundwater monitoring, as well as men’s reluctance to allow their wives to participate. This is in contrast to a high number of men willing to participate. Citizen science as an entry point for community-based groundwater governance relies on (i) the active involvement of myriad actors (including men and women citizens) whose actions interact with the hydrological processes; and (ii) volunteer interest (i.e., willingness to participate). A gender-sensitive approach to programs, gender awareness training, and partnerships with organizations working for women’s empowerment, natural resource management and adult literacy are recommended to support a citizen science approach to groundwater monitoring.
18 Gumindoga, W.; Rientjes, T. H. M.; Haile, Alemseged Tamiru; Makurira, H.; Reggiani, P. 2019. Performance of bias-correction schemes for CMORPH rainfall estimates in the Zambezi River Basin. Hydrology and Earth System Sciences, 23(7):2915-2938. [doi: https://doi.org/10.5194/hess-23-2915-2019]
Rainfall patterns ; Precipitation ; Estimation ; Satellite observation ; Performance evaluation ; River basins ; Water resources ; Weather forecasting ; Meteorological stations ; Rain gauges / Botswana / Malawi / Mozambique / Zambia / Zimbabwe / Zambezi River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H049387)
https://www.hydrol-earth-syst-sci.net/23/2915/2019/hess-23-2915-2019.pdf
https://vlibrary.iwmi.org/pdf/H049387.pdf
https://vlibrary.iwmi.org/pdf/H049387.pdf
(4.60 MB) (4.60 MB)
Satellite rainfall estimates (SREs) are prone to bias as they are indirect derivatives of the visible, infrared, and/or microwave cloud properties, and hence SREs need correction. We evaluate the influence of elevation and distance from large-scale open water bodies on bias for Climate Prediction Center-MORPHing (CMORPH) rainfall estimates in the Zambezi basin. The effectiveness of five linear/non-linear and time–space-variant/-invariant bias-correction schemes was evaluated for daily rainfall estimates and climatic seasonality. The schemes used are spatio-temporal bias (STB), elevation zone bias (EZ), power transform (PT), distribution transformation (DT), and quantile mapping based on an empirical distribution (QME). We used daily time series (1998–2013) from 60 gauge stations and CMORPH SREs for the Zambezi basin. To evaluate the effectiveness of the bias-correction schemes spatial and temporal crossvalidation was applied based on eight stations and on the 1998–1999 CMORPH time series, respectively. For correction, STB and EZ schemes proved to be more effective in removing bias. STB improved the correlation coefficient and Nash–Sutcliffe efficiency by 50 % and 53 %, respectively, and reduced the root mean squared difference and relative bias by 25 % and 33 %, respectively. Paired t tests showed that there is no significant difference (p- q) plots. The spatial cross-validation approach revealed that most bias-correction schemes removed bias by >28 %. The temporal cross-validation approach showed effectiveness of the bias-correction schemes. Taylor diagrams show that station elevation has an influence on CMORPH performance. Effects of distance >10 km from large-scale open water bodies are minimal, whereas effects at shorter distances are indicated but are not conclusive for a lack of rain gauges. Findings of this study show the importance of applying bias correction to SREs.
19 Gumindoga, W.; Rientjes, T. H. M.; Haile, Alemseged Tamiru; Makurira, H.; Reggiani, P. 2019. Performance evaluation of CMORPH satellite precipitation product in the Zambezi Basin. International Journal of Remote Sensing, 40(20):7730-7749. [doi: https://doi.org/10.1080/01431161.2019.1602791]
Rain ; Precipitation ; Satellites ; Weather forecasting ; Performance evaluation ; River basins ; Meteorological stations ; Observation ; Hydrology ; Deltas / Botswana / Mozambique / Malawi / Zimbabwe / Zambia / Zambezi River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H049388)
(2.28 MB)
For evaluation of the Climate Prediction Center-MORPHing (CMORPH) satellite rainfall product in the Zambezi Basin, daily time series (1998–2013) of 60 rain gauge stations are used. Evaluations for occurrence and rain rate are at sub-basin scale and at daily, weekly, and seasonal timescale by means of probability of detection (POD), false alarm ratio (FAR), critical success index (CSI) and frequency bias (FBS). CMORPH predicts 60% of the rainfall occurrences. Rainfall detection is better for the wet season than for the dry season. Best detection is shown for rainfall rates smaller than 2.5 mm/day. Findings on error decomposition revealed sources of Hit, Missed and False rainfall bias. CMORPH performance (detection of rainfall occurrences and estimations for rainfall depth) at sub-basin scale increases when daily estimates are accumulated to weekly estimates. Findings suggest that for the Zambezi Basin, errors in CMORPH rainfall should be corrected before the product can serve applications such as in hydrological modelling that largely rely on reliable and accurate rainfall inputs.
20 Walker, D.; Parkin, G.; Gowing, J.; Haile, Alemseged Tamiru. 2019. Development of a hydrogeological conceptual model for shallow aquifers in the data scarce Upper Blue Nile Basin. Hydrology, 6(2):1-24. [doi: https://doi.org/10.3390/hydrology6020043]
Groundwater table ; Aquifers ; Hydrogeology ; Models ; Hydrometeorology ; Monitoring ; Surface water ; Discharges ; Wells ; Pumping ; Rain ; Rivers / Ethiopia / Upper Blue Nile Basin / Dangila
(Location: IWMI HQ Call no: e-copy only Record No: H049389)
(5.15 MB) (5.15 MB)
Rural communities in sub-Saharan Africa commonly rely on shallow hand-dug wells and springs; consequently, shallow aquifers are an extremely important water source. Increased utilisation of shallow groundwater could help towards achieving multiple sustainable development goals (SDGs) by positively impacting poverty, hunger, and health. However, these shallow aquifers are little studied and poorly understood, partly due to a paucity of existing hydrogeological information in many regions of sub-Saharan Africa. This study develops a hydrogeological conceptual model for Dangila woreda (district) in Northwest Ethiopia, based on extensive field investigations and implementation of a citizen science programme. Geological and water point surveys revealed a thin (3–18 m) weathered volcanic regolith aquifer overlying very low permeability basalt. Hydrochemistry suggested that deep groundwater within fractured and scoriaceous zones of the basalt is not (or is poorly) connected to shallow groundwater. Isotope analysis and well monitoring indicated shallow groundwater flow paths that are not necessarily coincident with surface water flow paths. Characteristics of the prevalent seasonal floodplains are akin to “dambos” that are well-described in literature for Southern Africa. Pumping tests, recharge assessments, and hydrometeorological analysis indicated the regolith aquifer shows potential for increased utilisation. This research is transferrable to the shallow volcanic regolith aquifers that overlie a substantial proportion of Ethiopia and are prevalent throughout the East African Rift and in several areas elsewhere on the continent.
Powered by DB/Text WebPublisher, from
