Aquascope Facts
Exchange of water to the Baltic occurs primarily through the Öresund and the Belt. At the Great Belt, a surface current flows through these inlets and via a 22-25 m deep channel. About 70% of the water that flows into the Baltic flows via the Great Belt. The Baltic has a volume of about 21 000 km3 with a little influx of oceanic salt water. A large influx of freshwater occurs from rain and those rivers that flow into the Baltic. This influx is about 660 km3 per annum and this makes the Baltic more or less brackish. Discharge of brackish surface water from the Baltic is about 960 km3 per annum, while the influx of salty bottom water via the Great Belt and the Öresund is about 475 km3 per annum.
   Excessive influxes of salt water to the Baltic occur only under extreme circumstances, for example after a long period of strong westerly winds. Water is then pressed in against the Swedish west coast, while at the same time Baltic water is pressed to the east allowing a large influx of salt water through the Great Belt and the Öresund. This infux of salt water from the North Sea to the Baltic is of vital importance as it oxygenates the deeper areas that are often affected by severe and protracted periods of oxygen deficency.

Coastal waters are close to us

Sailing fun
Our coasts are important, partly as a source of income and work and partly for recreation and relaxation. We are many that use the coastal areas for sailing, diving, bathing and other recreational activities, but these areas are also of vital importance for fishing, aquaculture and other related industries. Unfortunately, our coastal areas are plagued by spills, discharges and other environmental disturbances. The consequences of these environmental problems vary from area to area, because the size of the discharges and interference are usually unequally distributed and because varying winds and currents can either spread or concentrate the pollutants.
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A splendid outing ?
Problems and expectations
”It was better before"
Seawater and soluble salts
The sea moves
Coastal waters are close to us
What is eutrofication?
Sources of over-fertilization
How the open masses of water are effected
How shallow bays are effected
What can we do?
Alga harvest

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Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson