The powerful storm which caused sea levels to rise in coastal areas may prove beneficial for the water quality of the Gulf of Finland. The narrow body of water has suffered from a lack of oxygen at its bottom, and the powerful flow of new water in and out of the gulf could improve the situation somewhat.
The level of the sea rose to about a metre and a half above average. In Hamina, further east, the rise was about two metres.
The water was at a high level for an exceptionally long time. The rise began on Saturday night, and the water level did not begin to come down in Helsinki until 2:00 PM Sunday.
Contributing to the phenomenon were a number of factors: a strong westerly wind, a deep low-pressure system, an exceptionally large volume of water in the Baltic Sea, and a back-and-forth oscillation of the water.
However, experts do not believe that the storm is bringing a hoped-for pulse of salty oxygen-rich water from the North Sea through the Straits of Denmark into the Baltic. This usually happens in the wake of a high-pressure system when the water level in the Baltic is fairly low. Before the storm, the Baltic Basin was quite full. Heikki Pitkänen of the Finnish Environment Institute nevertheless feels that the storms of the autumn and winter have probably improved the oxygen situation of the deeper parts of the Gulf of Finland.
