EU study finds climate change threatens Baltic Sea ecosystem
EU-funded researchers have found that the sea surface temperature of the Baltic Sea was warmer in the past and the oxygen depletion was stronger than what current figures show. The INFLOW project, 1 of 16 BONUS+ ('Multilateral call for research projects within the Joint Baltic Sea Research Programme') projects, is developing a model for natural variability in marine ecosystems that will fuel our understanding of how the changes will affect the Baltic Sea in the long run. BONUS+ is jointly funded by national programmes of the Baltic countries to the tune of EUR 22 million, of which EUR 7.27 million is provided via a grant under the ERA-NET Plus scheme of the EU's Seventh Framework Programme (FP7).
The BONUS network started as an ERA-NET and gathers research funding organisations from the Baltic Sea area, namely: Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, the Russian Federation and Sweden.
Climate change, rapid population growth and intensified use of marine and coastal areas are threatening marine environments the world over. Researchers at the Geological Survey of Finland have found that the Baltic Sea — and the plants and animals that depend on it for their survival — are at the forefront of the battle against these influences.
'The extent of oxygen depletion was already a big problem in the Baltic Sea a thousand years ago, despite minimum interference from human activities,' says INFLOW coordinator Aarno Kotilainen, a professor of research at the Geological Survey of Finland. 'Then the climate cooled and the rate of oxygen depletion decreased. However, the climate got warmer again in the 20th century, which in turn increased oxygen depletion.'
Professor Kotilainen says: 'Some estimates suggest that climate change in the Baltic Sea area causes sea surface temperatures to rise, increases winds and shortens the ice-cover season. Changes in the hydrography and biogeochemical processes of the Baltic Sea may influence the entire ecosystem.' He notes that due to the 'complex cause-and-effect relationships [it is] very difficult to assess the scope and trends of these impacts'.
However, it should be noted that these trends, overall, translated into a discouraging forecast for the future, as the external load on the Baltic Sea continues to increase in the wake of growing human activity.
The INFLOW partners are using a modelling approach to examine marine sediments from the Baltic Sea in order to find out more about the past state of the sea — up to as long as 6 000 years ago — and to attempt to understand the likely effects of climate change on it and the wider North Atlantic region.
The new information will shed light on sea surface temperature, sea ice cover and eutrophication levels at different times. The scientists will then use this data to produce model simulations that will provide selected scenarios of the impact of natural and human-induced climate change on the Baltic Sea ecosystem. This information, they say, will be vital in helping draft plans for the sustainable use of marine areas and in preparing for the impacts of climate change.
Scientists have been aware for many years of the declining health of the Baltic Sea. For example, each summer more of the sea is covered in algae blooms as a result of pollution caused by nitrates and phosphates from intensive agriculture. These algae consume oxygen at the expense of fish and other forms of life. Over-fishing is another activity that poses a significant challenge to the sea's ecosystem.
These threats, along with other difficulties facing the region, are being treated under the EU's Baltic Sea Regional Strategy, which aims at coordinating action by the EU, Member States, regions and pan-Baltic organisations, financing institutions and non-governmental bodies to promote a more balanced developed of the region.