Effects of climate change on the Baltic Sea region

Climate change is a global phenomenon but its regional effects are varied. Information about the current state of the region and projections are urgently needed in order to plan effective adaptation measures. Professor Hans von Storch, climate expert at the GKSS, is heading a group of 80 scientists from 13 states bordering the Baltic Sea in efforts to describe climatic changes in the Baltic Sea region, and to set up possible scenarios up to 2100. The initiative is coordinated by the BALTEX office at GKSS. The BACC report is a regional version of the IPCC report on global climate change,” says von Storch.

The air temperature in the northern Baltic Sea basin rose by about one degree Celsius in the last century, while in the south, an increase of only 0.7 degrees was recorded. Without effective countermeasures, the air temperature could rise by four to six degrees in the north by 2100 and by three to five degrees in the southern area, leading to a reduction of 50 to 80 per cent in the winter ice cover of the Baltic Sea. The experts also anticipate more precipitation in the winter and drier summers. The possible increase in precipitation – which could also reduce in average salinity – could result in stronger inflow of nutrients into the Baltic Sea, which could enhance eutrophication and algae growth. The water temperature could also rise. These changes would affect the whole ecosystem, from bacteria and algae to commercial fish species such as cod. In the future, the Baltic ringed seal could have more difficulty in finding ice surfaces in winter that they require for reproduction.

On the other hand, vegetation on land would probably grow more profusely and spring would come earlier. These findings should be interpreted with care, as von Storch emphasises: “Scenarios are plausible descriptions of possible futures.” An updated version of the BACC report is planned in five years. “By then we will know a great deal more about the prospects and effects of climate change, and we can make more detailed comments on adaptation strategies,” explains von Storch.

Further information: www.baltex-research.eu/BACC/