Climate change impacts and vulnerability in Europe 2016

Climate change impacts on environmental systems
4.3.3 River floods
Key messages
• Almost 1 500 floods have been reported for Europe since 1980, of which more than half have occurred since 2000.
• The number of very severe flood events in Europe increased over the period 1980–2010, but with large interannual
variability. This increase has been attributed to better reporting, land-use changes and increased heavy precipitation in
parts of Europe, but it is not currently possible to quantify the importance of these factors.
• Global warming is projected to intensify the hydrological cycle and increase the occurrence and frequency of flood events
in large parts of Europe.
• Pluvial floods and flash floods, which are triggered by intense local precipitation events, are likely to become more
frequent throughout Europe. In regions with projected reduced snow accumulation during winter, the risk of early spring
flooding could decrease. However, quantitative projections of changes in flood frequency and magnitude remain highly
uncertain.
Relevance
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) (EC, 2013).
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
(e.g. Chorynski et al., 2012; EEA, 2016a). According to
the NatCatSERVICE database ( 52 ), almost 1 500 flood and
wet mass movement events happened in EEA member
countries ( 53 ) 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. Information about economic damages
from floods is presented in Sections 5.1 and 6.3; their
impacts on human health are discussed in Section 5.2.
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
(Alfieri et al., 2014). The EU Floods Directive (EC, 2007b)
has improved this situation only to a limited extent so
far (EEA, 2016a).
Past trends
Figure 4.12 shows that the number of very severe flood
events in Europe increased over the period 1980–2010,
but with large interannual variability. The underlying
data is obtained from a combination of information
available in global databases such as the Dartmouth
Flood Observatory ( 54 ) and the Emergency Events
Database (EM-DAT) of the Centre for Research on the
( 52 ) NatCatSERVICE (http://www.munichre.com/natcatservice) is one of the most comprehensive natural catastrophe loss databases, managed
by Munich Reinsurance Company (Munich RE), based in Munich, Germany. As a proprietary database, it is not publicly accessible. The entire
Munich RE dataset, which was provided to the EEA under institutional agreement (June 2014), consists of 4 918 records and covers the period
1980–2013.
( 53 ) http://www.eea.europa.eu/about-us/countries-and-eionet.
( 54 ) http://floodobservatory.colorado.edu.
140 Climate change, impacts and vulnerability in Europe 2016 | An indicator-based report