Global sea level affects the level of the Baltic

The total volume of water in the global oceans affects the sea level in our seas. The volume of the global ocean is determined partly by the ocean temperature and by how much water is stored on land in reservoirs and aquifers, and as ice in the form of glaciers, Antarctic ice and Greenland ice. The long-term change in sea level around Sweden is a combination of the global sea level and the local Swedish land rise since the last ice age.

Global warming has increased the volume of the world oceans. Land ice has melted and added more water so that the combined effect is a rise of 19.5 cm since 1870. The total increase in sea level since the most recent ice age (10000 years ago) is calculated to be 130 m.

During the last 2000-3000 years up until the end of the 1800s the global sea level appears to have remained more or less unchanged.

Analyses of Swedish sea level measurements show that the Baltic sea level has risen by around 20 cm since 1886, a speed of 1.7 mm/year. However over the last 30 years the average increase has been 3.4 mm/year. Calculations from the Intergovernmental Panel on Climate Change and from SMHI show that for the Swedish south coast the average sea level in the year 2100 will be between 22 and 72 cm above today’s level, even after taking into account the small amount of land rise.