Land rise and sea level

In the Bothnian Bay the land is rising by 10 mm/year, in the Bothnian Sea by 6-9 mm/year, in the Baltic Proper by -1 to +5 mm/year. Over the last 100 years the sea level has “dropped” by 100 cm in the Bay of Bothnia. Several sea inlets have become lakes and many harbours are now on land.

The highest coastlines from during and after the most recent ice age are 300 m higher than the current coastline in the Bothnian sea and 20 m higher in southern Sweden. When measuring sea level, compensation is made for the land rise effect as well as the change in the mean global ocean sea level so that a new, lower annual mean sea level value is calculated each year.

The land rise means that the effect of the wider global rise in sea level is reduced.