Water resources management & hydroclimatic data analysis in transboundary river basins under the influence of climate variability & water abstraction : Nile river basin

Water is a vital component for developing nations, as it is important for humanconsumption and domestic use, irrigation, and industry. The freshwater availability foreach country should be known or estimated to sustainably manage its available supply,or its share of available water in case of transboundary basins during the subsequentyears. The freshwater availability in the present and the future is governed by twofactors: the effects of climate change or climate variability and the effects of humaninduced factors. The climate change can be sensed from the increase or decrease ofprecipitation, increase in temperatures, and increased prevalence of heat waves,drought events and the degree of severity of the drought events in some areas andincrease in floods in other areas. The human induced factors can be witnessed in thechange of land use, damming the rivers and excessive water obstruction andwithdrawal.The sustainable management of the available water resources is essential for futuregenerations and environmental resources, especially with the present and possiblefuture challenges in terms of increase in demand due to population growth and possiblechanges in precipitation. The application of water resources management practices ismore difficult to achieve in transboundary river basins. Sustainable management couldbe achieved by assessing the utilization of the water at a transboundary scale besidesstudying the possible impacts of climate change and applying mitigation measures toavoid water scarcity in downstream countries.The problems facing transboundary river basins are very complicated and there is aneed to study the problems occurring due to the human interventions and climate change or climate variability, which will give a solid ground to determine how muchthe river flow is being affected qualitatively and/or quantitively and try to find suitableeffective solutions for each of them.In this thesis the case of the Nile river basin will be representative of several sharedriver basins. The Nile river basin is third biggest river basin in the world and the secondlargest basin in Africa after the Congo basin in terms of area. It is shared betweeneleven countries and covers about 10% of African land.This thesis aims to present an analytical framework to determine how the riverdischarge has been affected by the influence of both climate variability and humaninduced factors. The findings from this thesis can support better understanding of thechanges occurring in river discharge due to coupled impact of climate variability andriver damming. The study of the changes occurring in the river discharge due to climatevariability and human intervention can lead to better planning for sustainablemanagement practices of water resources in transboundary river basins especially inarid and semi-arid regions.River flows have different fluctuations in river discharge as a result of the influence ofthe change in climate and human influence. The main aim of this research is to measurehow the climate variability and human intervention affect the river flow either as anincrease or a decrease in river discharge. The change in river discharge occurs basedon the degree of intervention and the climatic conditions. Thus, the relation betweenthe degree of human intervention and climate variability to the river discharge couldor might help in taking the optimum procedure in the sustainable management of waterresources, and help in negotiations between riparian countries to reach to a suitable treaty saving the rights of both upstream countries and downstream countries, andestablish effective measure(s) to mitigate the water scarcity crises.The objectives are to analyze the river discharge reaching the downstream countries inthe past, and how the human induced factors and climate variability in terms of changesin trend and the occurrence of drought events affected the river discharge.This has been addressed by assessing climate variability in the study area. The researchincludes the studying and choosing of the best metrological dataset for the areas withscarce meteorological datasets. The analyses of precipitation data obtained from theGlobal Precipitation Climatology Centre (GPCC) and detecting if there is a trend,Parametric and non-parametric tests are applied to the metrological data as theprecipitation and temperature, in addition, the drought indices are calculated for thedifferent time windows. and subsequently calculating drought events in the mainbasins impacting on the downstream flow.Then river discharge data are analyzed using different hydraulic indices at key stationsin the downstream country and measuring the alterations occurring in the flow. Thedegree of alteration is a function of the number of civil engineering projects being inoperation and classified by time windows; pre-alteration is between 1900 and 1925,while the alteration period is between 1933 and 2012. The alteration period wasclassified into three periods based on the degree of alteration.The research includes analyzing the records of river discharge reaching Egypt for 112years. The total record of discharge (112 years) will be divided to time-windows basedon the degree of interventions, statistical analysis is applied to the discharge of eachtime window, the alteration in discharge is compared between the different time windows. Finally, the investigation of the water usage in the upstream countriesthrough existing structures and consumptive use of water.The different time windows in the study was between 1900 and 1925, 1933 and 1963,1964 and 1999, and between 2000 and 2012. It was found that the highest period withthe discharge alteration was the last period, and this period had the strongest droughtevents then came the period 1964—1999.The precipitation patterns had a decrease in the last two periods (1964—1999) and(2000—2012). The high alteration and strong drought events affected the riverdischarge in these two periods compared to the original period between 1900 and 1925.The results showed that there was no significant change in trends of the precipitationin the Nile basin and the major flow contributor sub-basins. There was a noticeabledecline in trend at the two key river discharge stations (Dongola and Tamaniatstations).The increased drought events affected the precipitation pattern in this period. Theinfluence of the human induced factors and how they can control the river dischargeincreased with the degree of intervention, especially in periods with low precipitationand river flow.The findings revealed that there are changes in the river flow regime caused by bothchanges in the rainfall pattern in addition to the regulation in the upstream countries.There is a direct relationship between the interventions in the upstream countries andchanges in the flow regime especially when coupled with drought events. Byincreasing the water usage upstream, there is an increase in the alteration of the flow downstream. The years between 2000 and 2012 were linked to the highest alterationsbetween the modified years.The proposed framework is a step forward in filling the gap in knowledge by analyzinghow the river discharge react climate variability coupled with human intervention inlarge river transboundary basins.The water resources future strategic plan could be built based on the river dischargesituation and how the river discharge is proportional to the variability in climate andhuman intervention.

Level dc:type.qualificationlevel

Doctoral (Level 8)

Year dc:date.issued

2020

Author dc:creator

• Ahmed, Y

Language dc:language

en

Identifier

oai:salford-repository.worktribe.com:1352801

OAI identifier oai:identifier

oai:salford-repository.worktribe.com:1352801