Changing Water Cycle Programme

The Changing Water Cycle Programme directly relates to delivery of the NERC Strategy (in particular Climate System, Sustainable Use of Natural Resources (SUNR) and Natural Hazards Science Themes) and UK Government's Strategic Goals with respect to the adaptation to, and mitigation of, climate change. The programme will have global dimensions and dimensions that focus specifically on the UK/European region and Southern Asia and take advantage of international collaboration opportunities. The programme will be fully multidisciplinary aiming to bring science understanding across the themes in a fully integrated way.

The hydrological cycle is changing with some evidence that it is intensifying; and now we know that the climate is changing and is expected to change in future even with major mitigation efforts. The very high levels of uncertainty in predictions of water-related variables, and the importance of these variables for climate impacts, suggests that this problem should be afforded comparable importance to the goal of constraining climate sensitivity. Progress is essential, and urgent, to provide decision makers with the information they need to anticipate and respond to the changes taking place.

Over the next few decades, climate change and demographic and economic drivers will add further pressure to the water and soil life support systems on which we depend. Mitigation and adaptation measures linked to the forecast changes in water availability tend to focus on the demand end of the water balance. Sustainable solutions to climate change impacts on the water cycle mean getting to grips with changes in water supply, at scales from catchment to regional, and with the contingent changes in soil physical and biogeochemical processes.

Clear signals of human induced impact on river flows are beginning to emerge. There is evidence to suggest that changes in weathering rates over the past 50 years due to changes in climate and land use are changing the chemistry of rivers. The challenge is to predict where the freshwater will land, when, in what volume and how it will be transported through and stored within the terrestrial system. We also need to understand the implications for terrestrial and freshwater systems of measures designed to manipulate water availability such as large-scale water treatment movements, mixing raw water of different origin, and pumping water underground for storage. This programme will contribute to the fundamental scientific understanding needed to inform the planning and implications of such human interventions.

The programme will develop an integrated, quantitative understanding of the changes taking place in the global water cycle, involving all components of the earth system, improving predictions for the next few decades of regional precipitation, evapotranspiration, soil moisture, hydrological storage and fluxes. The programme will work to understand how local to regional scale hydrological and biogeochemical processes are responding and will respond to changing climate and land use, together with their consequent impacts on the sustainable use of soil and water and investigate the consequences of the changing water cycle for water-related natural hazards, including floods and droughts, improving prediction and mitigation of these hazards.  This programme will address the urgent needs to understand the changes taking place now; predict changes that will take place over the next few decades; and, through LWEC, work with partners to build resilience, mitigate problems, and develop adaptive solutions.

The Programme was officially launched on 5 February 2009.

Living With Environmental Change partners involved:

• Natural Environment Research Council (NERC)
• Department for Environment, Food and Rural Affairs (Defra)
• Environment Agency (EA)
• Department of Energy and Climate Change (DECC)
• Scottish Environment Protection Agency (SEPA)
• Welsh Assembly Government
• Scottish Government