The variation in salinity in a geological time perspective can provide information about the changes in the Baltic Sea environment that can be expected as a result of a climate change. Researchers at Luleå University of Technology and the Laboratory for Isotope Geology at the Swedish Museum of Natural History have used the strontium isotopic composition of up to 7,000 years old, carbon-14-dated mussel shells to measure the Baltic Sea's historic salinity.
Climate change is likely to affect the salinity of the Baltic Sea, as this is mainly driven by precipitation, freshwater runoff and sea level variations in the Kattegat. In a hundred-year perspective, salinity indirectly influences the oxygen content of the bottom water, the return of nutrients from the bottom sediment to the water, and algae production. This will also affect the basic ecological conditions in the Baltic Sea.
In order to better address the Baltic Sea's environmental problems, increased knowledge about how climate change will affect salinity, and the indirect environmental effects of salinity changes. One way to increase knowledge about upcoming changes is to study the historical salinity variations that occurred in the Baltic Sea after the recent ice age.