Baltic Sea

On the 29 September 2006 between 60 − 70m depth convex shaped isotherms and isohalines
suggest an eddy spreading over most of the width of the channel. A strong slope in salinities
and oxygen from south to north suggests an eastward geostrophic ow on the northern ank
of the channel and a westward ow on the southern ank of the channel. This will be further
investigated by calculating the geostrophic velocities.
4.3.2 Geostrophic velocities
As already indicated in the CTD sections of the Stolpe Channel the density interface of the
deeper layers is tiled; the 7.8 kg/m 3 density interface for example is found in a depth of 52 m
at SFS, but in 65 m at SFN. The mean vertical current prole of the ADCP's u-component
(averaged over the 87 days of deployment) indicates a change in direction from a westward
ow to an eastward ow in a depth of 52 m in ADCP SFS. Fig. 4.13 (left panel) shows the
zero crossing of the mean current of ADCP SFN from westward to an eastward direction is in
a depth of 65 m.
Depth (m)
0
20
40
60
80
0
20
40
60
80
Depth (m)
100
0 5 10 15 20 25
Temperature ( o C)
0
20
40
60
80
100
4 6 8 10
Density (kg m 3 )
Jan 2006
May 2006
July 2006
Nov 2006
100
0
20
40
60
80
8 10 12 14
Salinity
100
0 2.5 5 7.5 10
Oxygen (ml/l)
Figure 4.7: Depth proles of temperature, salinity, density and oxygen of the central monitoring station
of the Stolpe Channel (BMP222) for January, May, July and November 2006.
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