Lake and river ice cover
Published (reviewed and quality assured)
Justification for indicator selection
The appearance of ice on lakes and rivers requires prolonged periods with air temperatures below 0 ⁰C. The deeper the lake, the more cold is needed to cool down the lake so that ice forms. Higher temperatures will affect the duration of ice cover, the freezing and thawing dates and the thickness of the ice cover.
Lake ice reduces underwater light and vertical mixing, that is, the exchange of water from different depth layers. The existence of lake ice, and the timing of lake ice break-up, is thus of critical ecological importance, influencing for instance the production and biodiversity of phytoplankton and the occurrence of winter fish kills.
- No rationale references available
- Observed change in duration of lake and river ice cover a) Danube River, at Budapest, 1876–2011 and b) Lake Kallavesi, Finland, 1833–2011.
- Ice break-up dates of lakes and rivers (day of the year)
Policy context and targets
Ice cover of rivers and lakes is one of the parameters that determine function of aquatic ecosystems. Preparing for climate change is a major challenge for water management in Europe. Climate change is not explicitly included in the text of the Water Framework Directive. However, water management under the WFD will have to deal with the challenges posed by climate change. The stepwise and cyclical approach of the WFD River Basin Management Plans (RBMPs) process makes it well suited to adaptively manage climate change impacts. In particular, the review of RBMPs every six years establishes a mechanism to prepare for and adapt to climate change.
No targets have been specified.
Related policy documents
Climate-ADAPT: Mainstreaming adaptation in EU sector policies
Overview of EU sector policies in which mainstreaming of adaptation to climate change is ongoing or explored
Climate-ADAPT: National adaptation strategies
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 later. This webportal provides information on all adaptation activities of the European Commission.
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 will enhance the preparedness and capacity of all governance levels to respond to the impacts of climate change.
Methodology for indicator calculation
Trend lines have been added.
Methodology for gap filling
No methodology references available.
EEA data references
- No datasets have been specified here.
External data references
- First Ice Appearance and Final Disappearance on Danube River, at Budapest, 1876–2011
- Data on Ice-breakup Dates and Freezing Dates of Lake Kallavesi, Finland, 1833-2011
Data sources in latest figures
Data sets uncertainty
Time series of lake and river ice cover are available from several lakes and rivers in Europe. It is not currently possible to provide a comprehensive picture of lake and river ice cover in Europe.
Further information on uncertainties is provided in Section 1.7 of the EEA report on Climate change, impacts, and vulnerability in Europe 2012 (http://www.eea.europa.eu/publications/climate-impacts-and-vulnerability-2012/)
No uncertainty has been specified
Short term work
Work specified here requires to be completed within 1 year from now.
Long term work
Work specified here will require more than 1 year (from now) to be completed.
Responsibility and ownership
EEA Contact InfoPeter Kristensen
Frequency of updates
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)
For references, please go to www.eea.europa.eu/soer or scan the QR code.
This briefing is part of the EEA's report The European Environment - State and Outlook 2015. The EEA is an official agency of the EU, tasked with providing information on Europe’s environment.
PDF generated on 23 May 2015, 07:14 PM