A new study by the University of Gothenburg reveals that a warmer climate will increase salinity in the Baltic Sea. Earlier, the science has believed that a warmer climate will increase river runoff to the Baltic Sea, thus making the sea less salty.

Researchers have reconstructed the freshwater flow to the Baltic from the 16th century onwards. During the past 500 years, warm periods have coincided with less freshwater in the Baltic Sea. Nevertheless, major regional differences are possible. As the warming climate increases the rainfall in the north and east, more freshwater flows to the northern Baltic and Gulf of Finland. The opposite occurs in the southern Baltic. The study shows that the decrease in the south is greater than the increase in the north, which means that overall the water will be saltier.

Already small changes in salinity of the Baltic Sea can have significant effects on the Baltic ecosystem. The sensitive ecosystem containing both marine and freshwater species depends on a balance salt and fresh water.

Read more in the interview of researcher Daniel Hansson.