River floods

Assessment versions

Published (reviewed and quality assured)

• No published assessments

Rationale

Justification for indicator selection

There are many different types of floods. They can be distinguished based on the source of flooding (e.g. rivers and lakes, urban storm water and combined sewage overflow, or seawater), the mechanism of flooding (e.g. natural exceedance, defence or infrastructural failure, or blockage) and other characteristics (e.g. flash flooding, snowmelt flood, or debris flows).

River floods are a common natural disaster in Europe, and — along with storms — are the most important natural hazard in Europe in terms of economic damage. They are mainly caused by prolonged or heavy precipitation events and/or snowmelt. River floods can result in huge economic losses as a result of damage to infrastructure, property and agricultural land, and indirect losses in or beyond the flooded areas, such as production losses caused by damaged transport or energy infrastructure. They can also lead to loss of life, especially in the case of flash floods, and displacement of people, and can have adverse effects on human health, the environment and cultural heritage.

Large areas throughout Europe have been affected by flooding since 2000, many of them even multiple times. According to the NatCatSERVICE database, almost 1 500 flood and wet mass movement events happened in EEA member countries in the period 1980–2013, with more than half of them since 2000. These floods have resulted in over 4 700 fatalities and caused direct economic losses of more than EUR 150 billion (based on 2013 values), which is almost one-third of the damage caused by all natural hazards. Less than a quarter of these damages were insured.

Despite the general agreement that Europe-wide or at least transnational-scale flood hazard maps have the potential for many applications, including climate change studies, only a few products exist, and it remains difficult to compile large consistent datasets. The EU Floods Directive has improved this situation only to a limited extent so far.

Scientific references

• IPCC, 2014: Europe. Kovats, R.S., R. Valentini, L.M. Bouwer, E. Georgopoulou, D. Jacob, E. Martin, M. Rounsevell, and J.-F. Soussana, 2014: Europe. In: Climate Change 2014: Impacts, Adaptation, and Vulnerability. Part B: Regional Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Barros, V.R., C.B. Field, D.J. Dokken, M.D. Mastrandrea, K.J. Mach, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, and L.L. White (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 1267-1326.

Indicator definition

• Number of flood phenomena with 'very high' severity

• Projected change in river floods with a return period of 100 years

Units

• Number of events (unitless)
• Percentage change (%)

Policy context and targets

Context description

In April 2013, the European Commission (EC) presented the EU Adaptation Strategy Package. This package consists of the EU Strategy on adaptation to climate change (COM/2013/216 final) and a number of supporting documents. The overall aim of the EU Adaptation Strategy is to contribute to a more climate-resilient Europe.

One of the objectives of the EU Adaptation Strategy is Better informed decision-making, which will be achieved by bridging the knowledge gap and further developing the European climate adaptation platform (Climate-ADAPT) as the ‘one-stop shop’ for adaptation information in Europe. Climate-ADAPT has been developed jointly by the EC and the EEA to share knowledge on (1) observed and projected climate change and its impacts on environmental and social systems and on human health, (2) relevant research, (3) EU, transnational, national and subnational adaptation strategies and plans, and (4) adaptation case studies.

Further objectives include Promoting adaptation in key vulnerablesectors through climate-proofing EU sector policies and Promoting action by Member States. Most EU Member States have already adopted national adaptation strategies and many have also prepared action plans on climate change adaptation. The EC also supports adaptation in cities through the Covenant of Mayors for Climate and Energy initiative.

In September 2016, the EC presented an indicative roadmap for the evaluation of the EU Adaptation Strategy by 2018.

In November 2013, the European Parliament and the European Council adopted the 7^th EU Environment Action Programme (7^th EAP) to 2020, ‘Living well, within the limits of our planet’. The 7^th EAP is intended to help guide EU action on environment and climate change up to and beyond 2020. It highlights that ‘Action to mitigate and adapt to climate change will increase the resilience of the Union’s economy and society, while stimulating innovation and protecting the Union’s natural resources.’ Consequently, several priority objectives of the 7^th EAP refer to climate change adaptation.

Targets

No targets have been specified.

Related policy documents

• 7th Environment Action Programme
  DECISION No 1386/2013/EU OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 20 November 2013 on a General Union Environment Action Programme to 2020 ‘Living well, within the limits of our planet’. In November 2013, the European Parliament and the European Council adopted the 7 th EU Environment Action Programme to 2020 ‘Living well, within the limits of our planet’. This programme is intended to help guide EU action on the environment and climate change up to and beyond 2020 based on the following vision: ‘In 2050, we live well, within the planet’s ecological limits. Our prosperity and healthy environment stem from an innovative, circular economy where nothing is wasted and where natural resources are managed sustainably, and biodiversity is protected, valued and restored in ways that enhance our society’s resilience. Our low-carbon growth has long been decoupled from resource use, setting the pace for a safe and sustainable global society.’
• A Blueprint to Safeguard Europe's Water Resources
  COMMUNICATION FROM THE COMMISSION TO THE EUROPEAN PARLIAMENT, THE COUNCIL, THE EUROPEAN ECONOMIC AND SOCIAL COMMITTEE AND THE COMMITTEE OF THE REGIONS A Blueprint to Safeguard Europe's Water Resources /* COM/2012/0673 final */
• Climate-ADAPT: Adaptation in EU policy sectors
  Overview of EU sector policies in which mainstreaming of adaptation to climate change is ongoing or explored
• Climate-ADAPT: Country profiles
  Overview of activities of EEA member countries in preparing, developing and implementing adaptation strategies
• DG CLIMA: Adaptation to climate change
  Adaptation means anticipating the adverse effects of climate change and taking appropriate action to prevent or minimise the damage they can cause, or taking advantage of opportunities that may arise. It has been shown that well planned, early adaptation action saves money and lives in the future. This web portal provides information on all adaptation activities of the European Commission.
• Directive 2007/60/EC of the European Parliament and of the Council on the assessment and management of flood risks
  Directive 2007/60/EC of the European Parliament and of the Council of 23 October 2007 on the assessment and management of flood risks (Text with EEA relevance) OJ L 288, 06/11/2007, p. 27–34
• EU Adaptation Strategy Package
  In April 2013, the European Commission adopted an EU strategy on adaptation to climate change, which has been welcomed by the EU Member States. The strategy aims to make Europe more climate-resilient. By taking a coherent approach and providing for improved coordination, it enhances the preparedness and capacity of all governance levels to respond to the impacts of climate change.

Methodology

Methodology for indicator calculation

The number of very severe flood events in Europe is obtained from a combination of information available in global databases such as the Dartmouth Flood Observatory and the Emergency Events Database (EM-DAT) of the Centre for Research on the Epidemiology of Disasters (CRED), data reported by EU Member States under the EU Floods Directive and an additional country consultation in all EEA member and cooperating countries.

Future changes in the risk of river floods in Europe have been simulated using a hydrological model driven by an ensemble of climate simulations. Of particular interest is the frequency analysis of flood peaks above the 100-year flood level, which is the average protection level of the European river network (albeit with significant differences).

Methodology for gap filling

Not applicable

Methodology references

• Alfieri et al. (2015): Global warming increases the frequency of river floods in Europe. Alfieri, L., Burek, P., Feyen, L. and Forzieri, G., 2015, 'Global warming increases the frequency of river floods in Europe', Hydrology and Earth System Sciences 19(5), 2247–2260 (DOI: 10.5194/hess-19-2247-2015).

Data specifications

EEA data references

• European past floods provided by European Environment Agency (EEA)

External data references

• Projected change in river floods with a return period of 100 years

Data sources in latest figures

Uncertainties

Methodology uncertainty

Not applicable

Data sets uncertainty

The data required for the indicator are river flow (extreme high flows). Time series can be observed or simulated for historical time periods and can be projected for future time windows, taking into account climate change and potentially also other drivers of change, such as land-use changes.

River flow and water level data are influenced by rainfall run-off and by hydromorphological changes of the river bed, e.g. through river engineering. Furthermore, homogeneous time series are generally shorter than those for meteorological data. Therefore, substantially more time may be required before statistically significant changes in hydrological variables can be observed, especially with respect to extreme and exceptional events (floods and droughts). Notwithstanding recent improvements of climate models to simulate large-scale patterns of precipitation and extreme events, projections of changes in precipitation and high extremes remain uncertain, especially at catchment and local scales. Projections of river floods are plagued by the highest levels of uncertainty, as they often depend on changes in single extreme events, whereas changes in average and low-flow conditions depend on changes in precipitation on longer time scales (i.e. monthly to seasonal), which are more robust.

The main data sources for Europe-wide studies of the impacts of extreme hydrological events and their changes are global databases for natural disasters. Recently, the EEA has compiled a European Flood Impact Database that combines information on past floods with significant observed impacts from global sources with the reporting by EU Member States for the Preliminary Flood Risk Assessment (PFRA). This database has been collecting information on flood hazards and their impacts since 1980. At the European level, these inventories could assist in tracking the trends in flood disaster losses and in mitigation programmes, for both monitoring and obtaining a clearer picture of the linkages between climate change, floods and losses from flooding. Also at the European level, guidance for recording and sharing disaster damage and loss data is under development for Europe, coherent with the Sendai Framework for Disaster Risk Reduction.

Rationale uncertainty

No uncertainty has been specified