Scenarios for sea level on the Finnish coast
Milla Johansson, Kimmo K. Kahma, Hanna Boman, Jouko Launiainen
Abstract
The linkage between global climate change and sea level on the Finnish coast was studied. Scenarios were calculated for the long-term mean sea level in the future, based on the global change scenarios given by the Intergovernmental Panel on Climate Change. The effects of global mean sea level, local land uplift and the water balance of the Baltic Sea were taken into account. The effect of the water balance was estimated with the North Atlantic Oscillation (NAO) index. In most cases the rise in water level is expected to balance the land uplift in the Gulf of Finland, and the past declining trend of the relative sea level is not expected to continue. In the Gulf of Bothnia, the stronger land uplift rate still results in a fall of the relative mean sea level in the future. The uncertainties in the scenarios are large. Scenarios for the intra-annual variability of the sea level were constructed by extrapolating the 20th century trends of increasing variability.