Sea surface temperature

Indicator Assessment
Prod-ID: IND-100-en
Also known as: CSI 046 , CLIM 013
Created 22 Nov 2016 Published 20 Dec 2016 Last modified 20 Dec 2016
All European seas have warmed considerably since 1870, and the warming has been particularly rapid since the late 1970s. The multi-decadal rate of sea surface temperature rise during the satellite era (since 1979) has been between 0.21 °C per decade in the North Atlantic and 0.40 °C per decade in the Baltic Sea. Globally averaged sea surface temperature is projected to continue to increase, although more slowly than atmospheric temperature.

Key messages

  • All European seas have warmed considerably since 1870, and the warming has been particularly rapid since the late 1970s. The multi-decadal rate of sea surface temperature rise during the satellite era (since 1979) has been between 0.21 °C per decade in the North Atlantic and 0.40 °C per decade in the Baltic Sea.
  • Globally averaged sea surface temperature is projected to continue to increase, although more slowly than atmospheric temperature.

What is the trend in surface water temperature across European seas?

Annual average sea surface temperature anomaly

Running average of 11 years
Data sources: Explore chart interactively

Past trends

The production of consistent, long time series of SST faces challenges owing to different measurement devices (in situmeasurements from ships and buoys, as well as remote measurements from satellites), associated different definitions (e.g. water depth and time of day of measurement), different bias correction methods, and different interpolation methods to account for incomplete spatial and temporal coverage. As a result, substantially different values for absolute SST and for SST trends may be reported for a particular ocean basin, depending on the underlying global or regional SST dataset. In fact, there is still considerable uncertainty about the trend in global SST for the recent period 1979–2012 [i]. Furthermore, observed SST trends for regional seas reflect the combined effects of anthropogenic warming and natural climate variability (e.g. Atlantic Multidecadal Oscillation) [ii]. Despite those uncertainties, it is undisputed that SST has been increasing globally and in Europe during the last century.

The current indicator primarily uses information from the Hadley Centre Sea Ice and Sea Surface Temperature (HadISST1) dataset [iii]. Information on the Mediterranean for the satellite era is complemented by data from the Copernicus Marine Environmental Monitoring Service (CMEMS). The trends, although not necessarily the absolute SST levels, are consistent between HadISST1 and available high-resolution SST datasets for the regional seas (Mediterranean Sea, Baltic Sea and North Sea). The trends reported here cannot be directly compared with those in previous versions of this indicator, which used different underlying datasets.

All European seas have warmed considerably since 1870, and the warming has been particularly rapid since the late 1970s (Figure 1). The multi-decadal rate of SST rise during the satellite era (1979–2015) has been between 0.21 °C per decade in the North Atlantic and 0.40 °C per decade in the Baltic Sea.

Projections

It is very likely that globally averaged ocean temperatures at the surface and for different ocean depths will further increase in the near-term and beyond. Owing to the thermal inertia of the ocean, global SST is projected to rise more slowly than atmospheric temperature [iv]. Quantitative SST projections are available only for some regional seas in Europe [v]. For the Baltic Sea, the increase in summer SST during the 21st century under medium to high emissions scenarios is projected to be about 2 °C in the southern parts and about 4 °C in the northern parts [vi]. An increase in harmful algal blooms, with increased risks to human health, ecosystems and aquaculture, has been projected for the North Sea and the Baltic Sea as a result of the projected warming [vii].


[i] D. L. Hartmann et al., ‘Observations: Atmosphere and Surface’, inClimate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, ed. T. F. Stocker et al. (Cambridge; New York: Cambridge University Press, 2013), 159–254, http://www.climatechange2013.org/report/full-report/, Table 2.6.

[ii] Diego Macias, Elisa Garcia-Gorriz, and Adolf Stips, ‘Understanding the Causes of Recent Warming of Mediterranean Waters. How Much Could Be Attributed to Climate Change?’,PLOS ONE 8, no. 11 (27 November 2013): e81591, doi:10.1371/journal.pone.0081591.

[iii] N. A. Rayner et al., ‘Improved Analyses of Changes and Uncertainties in Sea Surface Temperature Measured in Situ since the Mid-Nineteenth Century: The HadSST2 Dataset’,Journal of Climate 19, no. 3 (February 2006): 446–69, doi:10.1175/JCLI3637.1.

[iv] B. Kirtman et al., ‘Near-Term Climate Change: Projections and Predictability’, inClimate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, ed. T. F. Stocker et al. (Cambridge; New York: Cambridge University Press, 2013), 953–1028, http://www.climatechange2013.org/images/report/WG1AR5_Chapter11_FINAL.pdf.

[v] Macias, Garcia-Gorriz, and Stips, ‘Understanding the Causes of Recent Warming of Mediterranean Waters. How Much Could Be Attributed to Climate Change?’; Guillem Chust et al., ‘Biomass Changes and Trophic Amplification of Plankton in a Warmer Ocean’,Global Change Biology 20, no. 7 (July 2014): 2124–39, doi:10.1111/gcb.12562.

[vi] HELCOM, ‘Climate Change in the Baltic Sea Area: HELCOM Thematic Assessment in 2013’, Baltic Sea Environment Proceedings (Helsinki: Helsinki Commission, 2013).

[vii] Patricia M. Glibert et al., ‘Vulnerability of Coastal Ecosystems to Changes in Harmful Algal Bloom Distribution in Response to Climate Change: Projections Based on Model Analysis’,Global Change Biology 20, no. 12 (1 December 2014): 3845–58, doi:10.1111/gcb.12662.

Indicator specification and metadata

Indicator definition

  • Trend in average sea surface temperature anomaly in the global ocean and in Europe’s regional seas

Units

  • Temperature (°C)

Policy context and targets

Context description

In April 2013, the European Commission (EC) presented the EU Adaptation Strategy Package. This package consists of the EU Strategy on adaptation to climate change (COM/2013/216 final) and a number of supporting documents. The overall aim of the EU Adaptation Strategy is to contribute to a more climate-resilient Europe.

One of the objectives of the EU Adaptation Strategy is Better informed decision-making, which will be achieved by bridging the knowledge gap and further developing the European climate adaptation platform (Climate-ADAPT) as the ‘one-stop shop’ for adaptation information in Europe. Climate-ADAPT has been developed jointly by the EC and the EEA to share knowledge on (1) observed and projected climate change and its impacts on environmental and social systems and on human health, (2) relevant research, (3) EU, transnational, national and subnational adaptation strategies and plans, and (4) adaptation case studies.

Further objectives include Promoting adaptation in key vulnerable sectors through climate-proofing EU sector policies and Promoting action by Member States. Most EU Member States have already adopted national adaptation strategies and many have also prepared action plans on climate change adaptation. The EC also supports adaptation in cities through the Covenant of Mayors for Climate and Energy initiative.

In September 2016, the EC presented an indicative roadmap for the evaluation of the EU Adaptation Strategy by 2018.

In November 2013, the European Parliament and the European Council adopted the 7th EU Environment Action Programme (7th EAP) to 2020, ‘Living well, within the limits of our planet’. The 7th EAP is intended to help guide EU action on environment and climate change up to and beyond 2020. It highlights that ‘Action to mitigate and adapt to climate change will increase the resilience of the Union’s economy and society, while stimulating innovation and protecting the Union’s natural resources.’ Consequently, several priority objectives of the 7th EAP refer to climate change adaptation.

Targets

No targets have been specified.

Related policy documents

  • 7th Environment Action Programme
    DECISION No 1386/2013/EU OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 20 November 2013 on a General Union Environment Action Programme to 2020 ‘Living well, within the limits of our planet’. In November 2013, the European Parliament and the European Council adopted the 7 th EU Environment Action Programme to 2020 ‘Living well, within the limits of our planet’. This programme is intended to help guide EU action on the environment and climate change up to and beyond 2020 based on the following vision: ‘In 2050, we live well, within the planet’s ecological limits. Our prosperity and healthy environment stem from an innovative, circular economy where nothing is wasted and where natural resources are managed sustainably, and biodiversity is protected, valued and restored in ways that enhance our society’s resilience. Our low-carbon growth has long been decoupled from resource use, setting the pace for a safe and sustainable global society.’
  • 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 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

The current indicator primarily uses information from the Hadley Centre Sea Ice and Sea Surface Temperature (HadISST1) dataset. Information on the Mediterranean for the satellite era is complemented by data from the Copernicus Marine Environmental Monitoring Service (CMEMS).

Methodology for gap filling

Not applicable

Methodology references

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. For example, systematic observations of sea surface temperature began around 1880. More recently, these manual measurements have been complemented by satellite-based observations that have a high resolution in time and a wide geographical coverage, as well as by Argo floats that automatically measure temperature and salinity below the ocean surface. In contrast, the longest available time series of plankton from the Continuous Plankton Recorder (CPR) is around 60 years. Sampling was started in the North Sea in the 1950s and today a network covering the entire North Atlantic Ocean has been established.

Our understanding is improving of how climate change, in combination with the synergistic impacts of other stressors, can cause regime shifts in marine ecosystems, but additional research is still needed to untangle the complex interactions and their effects upon biodiversity. Ecological thresholds for individual species are still only understood in hindsight, i.e. once a change has occurred.

Rationale uncertainty

No uncertainty has been specified

Data sources

Generic metadata

Topics:

DPSIR: Impact
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)
Indicator codes
  • CSI 046
  • CLIM 013
Temporal coverage:
Geographic coverage:

Geographical areas

, , , ,

Contacts and ownership

EEA Contact Info

Trine Christiansen

EEA Management Plan

2016 1.4.1 (note: EEA internal system)

Dates

Frequency of updates

Updates are scheduled every 4 years
Filed under: ,
European Environment Agency (EEA)
Kongens Nytorv 6
1050 Copenhagen K
Denmark
Phone: +45 3336 7100