This environmental impact assessment for Kriegers flak ... - Vattenfall

PATHWAYS OF CURRENTS IN THE BALTIC
Salty seabed water enters through Öresund and passes
the Drogden threshold and then moves between Mön
and Kriegers Flak down towards the Darss threshold,
where it falls in under the Darss current. These two
currents continue anti-clockwise from the south-western
corner of the Arcona basin and follow along the
southern line towards Cape Arcona where they intermingle/mix.
Thereafter the salty water moves down
to the deep parts of the Arcona basin or continues
Inflow of salt-rich deep layer water into the Baltic, Hydromod
tion and exchange of the deep water of the Baltic.
The Þ gure above illustrates the salt and oxygen
content of the different Baltic basins.
The water balance of the Baltic Sea is characterized
by a yearly surplus of 470 km³ fresh water. This allows
a ß ow of bracken water with a salinity of eight PSU
from the Baltic into the Skagerak (water in the upper
layer). The surrounding waters of Skagerak have a very
much higher salinity, 33 PSU, and are hence considera-
PRESENTATION OF THE AREA 69
northeast along the narrow inlets of Bornholm. A part
of the Drogden current divides northeast of Kriegers
Flak and moves clockwise to join up with the westerly
Drogden current in the south-eastern corner of the
Arcona basin. Via the narrow inlet of Bornholm, the
salty seabed water in the Arcona basin moves further
east, ending up in the Gotland basin. Reference: On
the pathways and mixing of salt-water Plumes in the
Arcona Sea, 2003, H.U. Lass, IOW, Warnemünde.
bly heavier. This water plume with heavier water is the
source of a pressure gradient creating a ß ow of heavier
and saltier water from the Skagerak into the Baltic (the
water at the seabed). This is described as inland sea
circulation and is occurring during the summer half of
the year.
The current condition in the Baltic is very variable
and driven mainly by the wind, horizontal density
gradients and differences in the water level (Fennel