Dec 1994
SUMMARY
This report describes the results of a suite of five inter-related studies investigating the potential impacts of climate change on water resources in the UK, commissioned by the Water Directorate of the Department of the Environment.
The five studies addressed the impact of climate change on:
- River flow regimes in the UK.
- The demand for water.
- River water temperature.
- River water quality.
- Estuarine water quality.
A comprehensive report has been produced for each study, and this report aims just to summarise results. Each study draws a number of important conclusions, but the most general are:
- Climate change may have very significant effects on the amount of water available for use in the UK, particularly in summer and especially in the south and east.
- Climate change may result in a significant increase in demand for water in the south and east, over and above any increase caused by other factors. The increase is expected to equal about 4% of the amount currently put into public water supply in the region, and will be concentrated in summer months.
- Water quality is likely to be affected more by future changes in land use than by changes in climate per se, although there may be increased peak nitrate concentrations following flushing after long dry spells and dissolved oxygen contents in heavily-utilised lowland rivers are likely to decline. A change in flow regimes is more important for water quality than a change in water temperature.
- Although higher water temperatures are unlikely to have a significant effect on water quality, they are large enough to have serious impacts on freshwater ecosystems.
- A rise in sea level will have little significant effect on estuarine water quality, and hence the viability of freshwater abstraction points. Changes in freshwater inflows to an estuary are more important.
The studies highlighted the differences between different climate change scenarios, and indicated a few areas where physically-based models were needed to improve the simulation of the potential impacts of climate change.
Copies of the report are available from FWR, price £20.00, less 20% to FWR Members.