Indicator Assessment

Lake and river ice cover

Indicator Assessment

Prod-ID: IND-190-en

Also known as: CLIM 020

Published 20 Nov 2012 Last modified 11 May 2021

7 min read

Topics: Water and marine environment Climate change adaptation

This page was archived on 03 Feb 2017 with reason: No more updates will be done

The existence of ice cover and the timing of ice break-up influence the vertical mixing of lakes and are therefore of critical ecological importance.

The duration of ice cover on European lakes and rivers has shortened at a mean rate of 12 days per century over the last 150–200 years.

A further decrease in the duration of lake ice cover is projected with projected climate change.

This indicator will be discontinued in January 2017.

This indicator is discontinued. No more assessments will be produced.

Observed change in duration of lake and river ice cover

Note: Ice break-up dates and freezing dates of a) Danube River, at Budapest, 1876–2011 (5-year running average) and b) Lake Kallavesi, Finland, 1833–2011.

Data source:

Data provenance info is missing.

Downloads and more info

Past trends

The duration of ice cover in the northern hemisphere has shortened at a mean rate of 12 days per century over the last 150–200 years, resulting from a 5.8 day later ice cover and a 6.5 day earlier ice break-up on average [i].

There are, however, large differences across regions. At the Hungarian section of the River Danube, the date of first ice appearance has shifted 19–29 days later over the 1876–2011 period, while the date of final ice disappearance shifted 18–23 days earlier [ii] (see Figure 1.a). In Lake Kallavesi, eastern Finland the freezing date has shifted 15 days later in 1833–2011, while the breakup date has shifted 12 days earlier in 1822–2011 [iii] (see Figure 1.b).

Projections

One recent study has simulated changes in lake ice cover throughout the Northern Hemisphere (40– 75 °N) based on one global climate model driven by the SRES A2 emission scenario. The results indicate an overall decrease in the duration of lake ice cover of 15–50 days across regions by 2040–2079, compared to the baseline period 1960–1999 [iv]. The ice cover of lakes in regions where the ice season is already short or where ice cover only occurs in cold winters is generally more strongly affected by increasing temperature than that of lakes in colder regions [v]. However, the ecological consequences of reduced ice cover are expected to be lower in areas where ice cover normally is less frequent and ecosystems thereby are adapted to less ice or ice-free conditions.

[i] John J. Magnuson et al., „Historical Trends in Lake and River Ice Cover in the Northern Hemisphere“, Science 289, Nr. 5485 (August 9, 2000): 1743–1746, doi:10.1126/science.289.5485.1743; EEA, Impacts of Europe’s changing climate - 2008 indicator-based assessment. Joint EEA-JRC-WHO report EEA Report (Copenhagen: European Environment Agency, September 29, 2008), http://www.eea.europa.eu/publications/eea_report_2008_4.

[ii] Katalin Takács, „Changes in river ice regime of the River Danube“ (Eötvös Loránd University, 2011), ftp://152.66.121.2/Floodrisk/_DC/docs/4_28_kkaatta.pdf.

[iii] SYKE, „Lake ice in Finland - observed trends and future outlooks.“, Finnish Environment Institute, 2011, http://www.environment.fi/default.asp?contentid=373875&lan=EN.

[iv] Y. Dibike et al., „Response of Northern Hemisphere lake-ice cover and lake-water thermal structure patterns to a changing climate“, Hydrological Processes 25 (2011): 2942–2953, doi:10.1002/hyp.8068.

[v] G. A. Weyhenmeyer et al., „Large geographical differences in the sensitivity of ice-covered lakes and rivers in the Northern Hemisphere to temperature changes“, Global Change Biology 17 (2011): 268–275, doi:10.1111/j.1365-2486.2010.02249.x.

Supporting information

Indicator definition

Observed change in duration of lake and river ice cover a) Danube River, at Budapest, 1876–2011 and b) Lake Kallavesi, Finland, 1833–2011.

Units

Ice break-up dates of lakes and rivers (day of the year)

Rationale

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.

Scientific references

No rationale references available

Policy context and targets

Context description

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.

Targets

No targets have been specified.

Methodology

Methodology for indicator calculation

Data on Ice-breakup Dates and Freezing Dates of Lake Kallavesi, Finland, 1833-2011 provided by Finnish Environment Institute (SYKE), and data on First Ice Appearance and Final Disappearance on Danube River, at Budapest, 1876–2011 provided by Eötvös Loránd University, Institute of geography and earth sciences are displayed.

Trend lines have been added.

Methodology for gap filling

Not applicable

Methodology references

No methodology references available.

Uncertainties

Methodology uncertainty

Not applicable

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/)

Rationale uncertainty

No uncertainty has been specified

Data sources

First Ice Appearance and Final Disappearance on Danube River, at Budapest, 1876–2011
provided by Eötvös Loránd University, Institute of geography and earth sciences
Data on Ice-breakup Dates and Freezing Dates of Lake Kallavesi, Finland, 1833-2011
provided by Finnish Environment Institute (SYKE)

Other info

DPSIR: Impact
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)

Indicator codes

CLIM 020

Frequency of updates

This indicator is discontinued. No more assessments will be produced.

EEA Contact Info

Permalinks

Permalink to this version: b46ffd34589b42808ff8da675ded0a3b
Permalink to latest version: IND-190-en

Older versions

08 Sep 2008 - Lake and river ice cover

Geographic coverage

Danube River (Romania) Kallavesi (Kallavesi, Finland)

Temporal coverage

1833-2011

For references, please go to https://www.eea.europa.eu/data-and-maps/indicators/lake-and-river-ice-cover-1/assessment or scan the QR code.

PDF generated on 07 May 2024, 04:56 PM

Dates

First draft created:

12 Nov 2012, 04:27 PM

Publish date:

20 Nov 2012, 12:29 PM

Last modified:

11 May 2021, 11:50 AM

Topics

Topics: Water and marine environment Climate change adaptation