Climate change and water in the UK : past changes and future prospects: a climate change report card for water: Working technical paper

Climate change is expected to modify rainfall, temperatures and catchment hydrological responses across the world, and adapting to these water-related changes is a pressing challenge. This paper reviews the impact of climate change on water in the UK and looks at projections of future change. The natural variability of the UK climate makes change hard to detect; only historical increases in air temperature can be attributed to climate change, but over the last fifty years more winter rainfall has been falling in intense events. Future changes in rainfall and evapotranspiration could lead to changed flow regimes and impacts on water quality, aquatic ecosystems and the water available for use by people. Summer flows may decrease on average, but floods may become larger and more frequent. Water quality may decline as a result of higher water temperatures, lower river flows and increased algal blooms. Water demand may increase in response to higher summer temperatures, placing additional pressure on water resources. These changes affect many parts of everyday life, emphasising the importance of long-term adaptation that takes these possible changes into account.