Global and European sea-level rise

Assessment versions

Published (reviewed and quality assured)

• Global and European sea-level rise (CLIM 012) - Assessment published Nov 2012

Justification for indicator selection

Sea level is an important indicator of climate change because it is associated with significant potential impacts on settlements, infrastructure, people and natural systems. It acts on time scales much longer than those of indicators that are closely related to near-surface temperature change. Even if GHG concentrations were stabilised immediately, sea level would continue to rise for centuries.

Low-lying coastlines with high population densities and small tidal ranges are most vulnerable to sea-level rise, in particular where adaptation is hindered by a lack of economic resources or by other constraints. In Europe, the potential impacts of sea-level rise include flooding, coastal erosion, and the loss of flat coastal regions. Rising sea levels can also cause salt-water intrusion into low-lying aquifers and endanger coastal ecosystems and wetlands. Higher flood levels increase the risks to life and property, including sea dikes and other infrastructure, with possible follow-up effects on tourism, recreation and transportation functions. Damage associated with sea-level rise would frequently result from extreme events, such as storm surges, the frequency of which would increase as the mean sea level rises.

Scientific references:

• IPCC, 2007a. Cimate Change: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Solomon, S.; Qin, D.; Manning, M.; Chen, Z.; Marquis, M.; Averyt, K. B.; Tignor M. and Miller H. L. (eds.), Cambridge University Press, Cambridge, UK
• IPCC, 2007b. Climate Change: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Parry, M. L.; Canziani, O. F.; Palutikof, J. P.; van der Linden, P.J. and Hanson, C.E. (eds.), Cambridge University Press, Cambridge, UK.

Indicator definition

• Change in global mean sea level

• Trend in absolute sea level across Europe based on satellite measurements

• Trend in relative sea level at selected European tide gauge stations

• Contributions to the sea level budget since 1972

• Range of high-end estimates of global sea-level rise published after the IPCC AR4

Units

• mm/yr
• m/century

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 White Paper stresses the need to improve the knowledge base and to mainstream adaptation into existing and new EU policies. The European Commission will be publishing an EU Adaptation Strategy in 2013. A number of Member States have already taken action, and several have prepared national adaptation plans.

The European Commission and the European Environment Agency have developed the European Climate Adaptation Platform (Climate-ADAPT, http://climate-adapt.eea.europa.eu/) to share knowledge on observed and projected climate change and its impacts on environmental and social systems and on human health; on relevant research; on EU, national and subnational adaptation strategies and plans; and on adaptation case studies.

Targets

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 Climate Action: What is the EU doing about climate change?
  Activities of the EU regarding climate change (both mitigation and adaptation)
• White paper - Adapting to climate change: towards a European framework for action
  EU framework for adaptation to climate change, leading to a comprehensive EU adaptation strategy by 2013

Methodology

Methodology for indicator calculation

Sea-level changes are measured using tide gauges and remotely from space using altimeters.

Currently there are two main approaches to projecting future sea level: physically-based models that represent the most important known processes, and statistical models that apply the observed relationship between temperature or radiative forcing on the one hand and sea level on the other hand in the past and extrapolate it to the future. Both approaches produce a spread of results, which results in large uncertainties around future sea-level rise.

Methodology for gap filling

Not applicable

Methodology references

• Church and White (2011): Sea-Level Rise from the Late 19th to the Early 21st Century   Surveys in Geophysics, September 2011 , Volume 32 , Issue 4-5 , pp 585-602
• Woodworth and Player (2003): The Permanent Service for Mean Sea Level: An Update to the 21stCentury Journal of Coastal Research , Vol. 19, No. 2, Spring, 2003  
• Nicholls et al (2010): Sea-level rise and its possible impacts given a ‘beyond 4°C world’ in the twenty-first century doi: 10.1098/rsta.2010.0291 Phil. Trans. R. Soc. A 13 January 2011 vol. 369 no. 1934 161-181

Data specifications

EEA data references

• No datasets have been specified here.

External data references

• Sea-level rise and its possible impacts given a ‘beyond 4°C world’ in the twenty-first century
• Permanent Service for Mean Sea Level (PSMSL)
• Sea-Level Rise from the Late 19th to the Early 21st Century

Data sources in latest figures

Uncertainties

Methodology uncertainty

Not applicable

Data sets uncertainty

Changes in global average sea level result from a combination of several physical processes. Thermal expansion of the oceans occurs as a result of warming ocean water. Additional water is added to the ocean from a net melting of glaciers and small ice caps, and from the large Greenland and West Antarctic ice sheets. Further contributions may come from changes in the storage of liquid water on land, either in natural reservoirs such as groundwater or man-made reservoirs.

The locally experienced changes in sea level differ from global average changes for various reasons. Changes in water density are not expected to be spatially uniform, and changes in ocean circulation also have regionally different impacts. At any particular location there may also be a vertical movement of the land in either direction, for example due to the post-glacial rebound (in northern Europe) or to local groundwater extraction.

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