Sea surface temperature

Assessment versions

Published (reviewed and quality assured)

• No published assessments

Rationale

Justification for indicator selection

Sea surface temperature (SST) is relevant for monitoring of climate change because it reflects regional changes in ocean temperature, whereas OHC is estimated globally. SST is closely linked to one of the strongest drivers of climate in western Europe, the ocean circulation that is known as Atlantic Meridional Overturning Circulation (MOC) or alternatively as the great conveyor belt. This circulation carries warm upper waters north in the Gulf Stream and returns cold deep waters south. It is widely accepted that the MOC is an important driver of low-frequency variations in sea surface temperature on the time scale of several decades. It is also widely accepted that the NAO-index (a proxy of atmospheric variability) plays a key role in forcing variations in MOC as well as the northward extent of the Gulf Stream.

The MOC sensitivity to greenhouse warming remains a subject of much scientific debate, largely because its large natural variability and the scarcity of observations makes trend detection very difficult.

One of the most visible ramifications of increased temperature in the ocean is the reduced area of sea ice coverage in the Arctic polar region. There is an accumulating body of evidence suggesting that many marine ecosystems are also sensitive to changes in SST. For example, the spread of oxygen-free areas (so called dead zones) in the Baltic Sea in the past 1 000 years was strongly linked to above-average SST.

Scientific references

• IPCC, 2013. Climate Change: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T. F., D. Qin, G.-K. Plattner, M. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P. M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

Indicator definition

• Annual average sea surface temperature anomaly in the global ocean and in different European seas

• Mean annual sea surface temperature trend in European seas

Units

• Temperature (°C)

• Rate of temperature change (°C/yr)

Policy context and targets

Context description

In April 2013 the European Commission presented the EU Adaptation Strategy Package (http://ec.europa.eu/clima/policies/adaptation/what/documentation_en.htm). This package consists of the EU Strategy on adaptation to climate change /* COM/2013/0216 final */ and a number of supporting documents. One of the objectives of the EU Adaptation Strategy is Better informed decision-making, which should occur through Bridging the knowledge gap and Further developing Climate-ADAPT as the ‘one-stop shop’ for adaptation information in Europe. Further objectives include Promoting action by Member States and Climate-proofing EU action: promoting adaptation in key vulnerable sectors. Many EU Member States have already taken action, such as by adopting national adaptation strategies, and several have also prepared action plans on climate change adaptation.

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: Country information
  Overview of activities of EEA member countries in preparing, developing and implementing adaptation strategies
• 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
• 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.
• 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

Sea surface temperature datasets stem from the Hadley Centre (HADISST1 (global)), MOON-ENEA (Mediterranean Sea), and Bundesamt für Seeschifffahrt und Hydrographie (Baltic and North Seas), and MyOcean.

Methodology for gap filling

Not applicable

Methodology references

• Frankignoul and Kestenare (2005) Observed Atlantic SST anomaly impact on the NAO: an update Journal of Climate 18(19), 4089–4094. doi:10.1175/JCLI3523.1

Data specifications

EEA data references

• No datasets have been specified here.

External data references

• Global Ocean OSTIA Sea Surface Temperature and Sea Ice Reanalysis
• Sea surface temperature - Mediterranean Sea
• Sea surface temperature - Baltic and North Seas
• HadISST1 - Global sea ice and Sea Surface Temperature analyses

Data sources in latest figures

Uncertainties

Methodology uncertainty

Not applicable

Data sets uncertainty

In general, changes related to the physical and chemical marine environment are better documented than biological changes because links between cause and effect are better understood and often time series of observations are longer. For example, systematic observations of both sea-level and sea surface temperature were started around 1880 and are today complemented by observations from space that have high resolution in time and geographical coverage and by Argo floats that also automatically measure temperature and salinity below the ocean surface.

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