A recently released report on climate change in the Baltic Sea area looks into historical and more recent changes in the region’s climate and changes that are projected to take place in the future. The new assessment is an important contribution to the 2013 HELCOM Ministerial Meeting, to be held next Thursday in Copenhagen, Denmark. Climate is an important controlling factor for the marine ecosystem. The report examines possible future changes in the Baltic Sea and explains what future climate change may mean for the protection of the sea.

 

The report also contains proposals for action to counteract the expected negative impacts from climate change on the Baltic Sea ecosystem. This has been done to follow-up the needs for more stringent and supplementary actions due to climate change indicated by the HELCOM 2007 and 2010 Ministerial Meetings.

 

Highlights from the report:

-        The Baltic Sea region is warming faster than the Earth as a whole. On average since the late 19th century the increase in annual average surface air temperature has been 0.11˚C per decade in the northern Baltic and 0.08˚C in the southern Baltic compared to the global average of 0.05˚C per decade. The warming is anticipated to continue.

-        Annual average sea-surface water temperature has increased by up to 1˚C per decade since 1990 and a further increase of 2 to 4˚C is projected near the end of this century. There will be a drastic decrease in the amount of sea-ice cover and the length of the ice season in the Baltic Sea if the warming continues as expected.

-        Precipitation during the past century has tended to increase in winter and spring in the Baltic Sea region. Model simulations indicate that winter precipitation could continue to increase during this century. Patterns of river runoff tend to change considerably.

-        The volume of snow in the region is expected to decrease, particularly in the southern half of the region.

-        Sea-surface salinity may decrease and the change may be largest in the region of the Danish Straits, and small in the northern and eastern Baltic, and the smallest in the Bothnian Bay.

-        Surface sea level projections are associated with considerable uncertainty: mid-range scenarios project a 0.6 m and high-end scenarios a 1.1 m sea-level rise over this century.

-        Acidification that stems from increased CO2 concentrations in the atmosphere has been slightly offset by an increase in alkalinity; the decrease of 0.15 pH units expected for marine systems from the increased atmospheric CO2 concentrations has been diminished by roughly 0.03 units due to increased alkalinity from the catchment area.

-        Changes in ecosystem structure and functioning are expected as a result of climate change, warming in particular. Such changes would include shifts in the ranges of species and distribution of habitats, as well as a decrease of oxygen in the water.

-        Proposed actions to buffer the Baltic Sea ecosystem against the expected negative changes: reduction of nutrient inputs to the maximum allowable levels, overall reduction of human pressures stemming from activities such as shipping, fisheries and construction activities, and lastly, the report proposes strengthening of the network of marine protected areas so that it will ensure a safe space for species and habitats.

 

The previous assessment of climate change in the Baltic Sea Area was released in 2007 (HELCOM BSEP No. 111) and the broader technical book, Assessment of Climate Change for the Baltic Sea Basin, in 2008, published by Springer. The current assessment builds on and extends the previous assessment, and summarizes the current state of knowledge.

 

The report is a result of close collaboration between HELCOM and Baltic Earth, the successor programme to BALTEX. It is based on the Second Assessment of Climate Change for the Baltic Sea which is to be released in 2014. The material used for this assessment has been produced by more than 120 experts from the Baltic Sea region within the framework of BALTEX/Baltic Earth. The proposals for action stem from the work of HELCOM.

 

Download the report here.

 

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Note for editors:

The Baltic Marine Environment Protection Commission, usually referred to as HELCOM, is an intergovernmental organisation of the nine Baltic Sea coastal countries and the European Union working to protect the marine environment of the Baltic Sea from all sources of pollution and to ensure safety of navigation in the region. Since 1974, HELCOM has governed the ‘Convention on the Protection of the Marine Environment of the Baltic Sea Area’, more commonly known as the Helsinki Convention.

 

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For more information, please contact:

Ms. Maria Laamanen
Professional Secretary
HELCOM
Tel: +358 46 850 9198
Skype: helcom101
E-mail: maria.laamanen@helcom.fi 

 

Ms. Johanna Laurila
Information Secretary
HELCOM
Tel: +358 40 523 8988
Skype: helcom70
E-mail: johanna.laurila@helcom.fi