River flow

Assessment versions

Published (reviewed and quality assured)

• River flow (CLIM 016) - Assessment published Sep 2008

Justification for indicator selection

Water is an indispensable resource for human health, ecosystems and socio-economic activity. From a resource perspective, river flow is a measure of sustainable fresh water availability in a basin. Variations in river flow are determined mainly by the seasonality of precipitation and temperature, as well as by catchment characteristics such as geology, soils and land cover. River flow can be used as an indicator because changes in temperature and precipitation patterns due to global warming modify the distribution of water at the land surface, and consequently the annual water budget of river basins as well as the timing and seasonality of river flows. The consequent changes in water availability may adversely affect ecosystems and several socio-economic sectors such as water management, energy production, navigation, irrigation and tourism.
In view of projected global warming and the associated changes in water availability, it will become increasingly important to balance competing societal, industrial, agricultural and environmental demands. Sustainable options for mitigating the effects of changes in water availability include improved water efficiency, the re-use of water, and metering and water pricing to stimulate awareness and encourage water conservation.

Scientific references:

• References Alcamo, J.; Flörke, M. and Märker, M., 2007. Future long-term changes in global water resources driven by socio-economic and climatic change. Hydrological Sciences Journal 52: 247-275. Andréasson, J.; Bergström, S.; Carlsson, B.; Graham, L.P. and Lindström, G., 2004. Hydrological change -- climate change impact simulation for Sweden. Ambio 33: 228-234. Arnell, N. W., 2004. Climate change and global water resources: SRES emissions and socio-economic scenarios. Global Environmental Change 14: 31-52. Barnett, T. P.; Adam, J. C. and Lettenmaier, D. P., 2005. Potential impacts of a warming climate on water availability in snow-dominated regions. Nature 438: 303-309. Birsan, M. V.; Molnar, P.; Burlando, P. and Pfaundler, M., 2005. Streamflow trends in Switzerland. Journal of Hydrology 314: 312-329. Dankers, R.; Feyen, L., 2008a. Climate change impacts on river flow in Europe (manuscript in  preparation). Dixon, H.; Lawler, D. M. and Shamseldin, A. Y., 2006. Streamflow trends in western Britain. Geophysical Research Letters 23: L19406, DOI:10.1029/2006GL027325. Hisdal, H.; Holmqvist, E.; Kuusisto, E.; Lindström, G. and Roald, L. A., 2007. Has streamflow changed in the Nordic countries? Climate Research, submitted. Jasper, K.; Calanca, P.; Gyalistras, D. and Fuhrer, J., 2004. Differential impacts of climate change on the hydrology of two alpine rivers. Climate Research 26: 113-125. Lindström, G. and Bergström, S., 2004. Runoff trends in Sweden 1807-2002. Hydrological Sciences Journal 49 (1): 69-83. Milly, P. C. D.; Dunne, K. A. and Vecchia, A. V., 2005. Global pattern of trends in streamflow and water availability in a changing climate. Nature 438: 347-350. Wade, S.; Vidal, J.-P.; Dabrowski, C.; Young, P. and Romanowicz, R., 2005. Effect of climate change on river flows and groundwater recharge. A practical methodology. Trends in UK river flows: 1970-2002. UKWIR Report 05/ CL/04/5. Wang, W.; Van Gelder, P. H. A. J. M. and Vrijling, J. K., 2005. Detection of changes in streamflow series in western Europe over 1901-2000. Water Science and Technology: Water Supply 5 (6): 289-299. Werritty, A., 2002. Living with uncertainty: climate change, river flows and water resource management in Scotland. The Science of the Total Environment 294: 29-40.

Indicator definition

• Modelled change in annual river flow between 1971-1998 and 1900-1970
• Projected change in mean seasonal and annual river flow between 2071-2100 and the reference period 1961-1990
• Projected change in daily average river flow between 2071-2100 and the reference period 1961-1990
  

Units

http://www.eea.europa.eu/publications/eea_report_2008_4/pp76-110CC2008_ch5-4to6_Water_quantity_and_quality.pdf

Policy context and targets

Context description

In April 2009 the European Commission presented a White Paper on the framework for adaptation policies and measures to reduce the European Union's vulnerability to the impacts of climate change. The aim is to increase the resilience to climate change of health, property and the productive functions of land, inter alia by improving the management of water resources and ecosystems. More knowledge is needed on climate impact and vulnerability but a considerable amount of information and research already exists which can be shared better through a proposed Clearing House Mechanism. The White Paper stresses the need to mainstream adaptation into existing and new EU policies. A number of Member States have already taken action and several have prepared national adaptation plans. The EU is also developing actions to enhance and finance adaptation in developing countries as part of a new post-2012 global climate agreement expected in Copenhagen (Dec. 2009). For more information see: http://ec.europa.eu/environment/climat/adaptation/index_en.htm

Targets

No targets have been specified

Related policy documents

No related policy documents have been specified

Methodology

Methodology for indicator calculation

http://www.eea.europa.eu/publications/eea_report_2008_4/pp76-110CC2008_ch5-4to6_Water_quantity_and_quality.pdf

Methodology for gap filling

Methodology references

No methodology references available.

Data specifications

EEA data references

• No datasets have been specified here.

External data references

• Global trends in streamflow and water availability
• Global Runoff Database

Data sources in latest figures

Uncertainties

Methodology uncertainty

Data sets uncertainty

Rationale uncertainty

No uncertainty has been specified