Climate change impacts on hydrology and water resources of the Upper Blue Nile River Basin, Ethiopia

Climate change / Hydrology / River basins / Runoff / Precipitation / Models / Dams / Operating policies / Water power / Drought / Analysis / Africa / Ethiopia / Egypt / Sudan / Upper Blue Nile River Basin

Improved water and land management in the Ethiopian highlands: its impact on downstream stakeholders dependent on the Blue Nile; Intermediate Results Dissemination Workshop February 5-6, 2009, Addis Ababa, Ethiopia

River basin management, Watershed management, Farming systems, Water balance, Reservoirs, Water supply, Irrigation requirements, Irrigation programs, Simulation models, Sedimentation, Rainfall-Runoff relationships, Erosion, Soil water, Water balance, Soil conservation, Institutions, Organizations, Policy, Water governance, International waters, Institutional and Behavioral Economics, Land Economics/Use, Resource /Energy Economics and Policy,

Simulating the hydrology of small coastal ecosystems in conditions of limited data

Hydrology / Simulation / Ecosystems / Lagoons / Estuaries / Irrigation effects / Sri Lanka / South Africa / Karagan Lagoon / Bundala Lagoon

The use of remote sensing data for drought assessment and monitoring in southwest Asia

Drought / Monitoring / Indicators / Assessment / Remote sensing / Asia

Setting the agenda: Climate change adaptation and mitigation for food systems in the developing world

New agricultural development pathways are required to meet climate change adaptation and mitigation needs in the food systems of low-income countries. A research and policy agenda is provided to indicate where innovation and new knowledge are needed. Adaptation requires identifying suitable crop varieties and livestock breeds, as well as building resilient farming and natural resources systems, institutions for famine and crop failure relief, and mechanisms for rapid learning by farmers. Mitigation requires transitioning to ‘low climate impact’ agriculture that reduces emissions while achieving food security, economic well-being and sustainability. Efficient interventions, incentives for large-scale shifts in practices, and monitoring systems are required. Integrated assessments of adaptation and mitigation are needed to better understand the synergies and trade-offs among outcomes

Climate change, water and agriculture in the Greater Mekong subregion

The impacts of climate change on agriculture and food production in Southeast Asia will be largely mediated through water, but climate is only one driver of change. Water resources in the region will be shaped by a complex mixture of social, economic and environmental factors. This report reviews the current status and trends in water management in the Greater Mekong Subregion; assesses likely impacts of climate change on water resources to 2050; examines water management strategies in the context of climate and other changes; and identifies priority actions for governments and communities to improve resilience of the water sector and safeguard food production

Basin closure and environmental flow requirements

A river basin is referred to as 'closed' when all its river flow is allocated to different uses. Water requirements of freshwater-dependent ecosystems, often referred to as 'environmental flow requirements', only recently started to receive attention. This 'user' is still often neglected in river basin management. This paper discusses the place of environmental flow requirements in basin water resources, examines a global pattern of closed/closing river basins and advocates the need to set environmental requirements in advance of major basin developments. It is also suggested that to ensure sustainable water resources development in the future, it is necessary to revise the content of 'basin closure' by explicitly introducing environmental flow requirements into basin water management and supporting it with relevant policies

Simulating the hydrology and mouth conditions of small, temporarily closed/open estuaries

Many small estuaries and coastal lagoons in different parts of the world may be classified as temporarily closed/open ecosystems. They are blocked off from the sea for varying lengths of time by a sand bar, which forms at the estuarine mouth. The lengths of the closed and open phases, which are determined primarily by the interaction of river inflow and the sea in the mouth region, affect the structure and functioning of the estuarine biotic community. Freshwater inflow to such estuaries is normally not measured, and observations on the duration of estuarine mouth openings/closures are very scarce. As a result, relevant management decisions are often made on the basis of general experience and intuitive judgment. This paper describes an innovative approach for linking hydrologic data to mouth state in ungauged estuaries. A key characteristic in the method is the stream/river flow duration curve. It is first established for a daily index, which reflects the upstream catchment wetness and is calculated using rainfall information from the nearest rain gauge(s). This duration curve is then used to convert the current precipitation index time series into a continuous daily inflow time series at the ungauged estuarine mouth location. The conversion is based on the assumption that precipitation index values in a small catchment, and daily inflows to the estuarine mouth correspond to similar probabilities on their respective duration curves. The paper further illustrates how the generated inflow data could be used for the simulation of a continuous time series of estuary mouth openings/closures. Inflows are routed through a reservoir model, and the estuary mouth is considered open on days when the spillage from an estuarine "reservoir? occurs. The approach is illustrated using limited observed data on estuary mouth conditions from the South African coastline