728 
NOAA-scene. At the northern mouth of Öresund the 
discharge of cold water to Kattegatt along the 
Swedish side is clearly visible in both scenes. This 
tendency might be due to the Coriolis force which 
tries to move water to the right on the northern 
hemisphere . The cold water plume originating from 
Öresund seems to be more extended in the NOAA-scene 
than in the Landsat-scene. This could partly be ex 
plained by the difference in time for the two detec 
tions (field measurements indicated a northbound 
current). However, one could also expect that the 
plume looks smaller in the Landsat scene due to the 
smaller temperature sensitivity of Landsat. 
Fig. 7 shows a full resolution TM 6 image of Öre 
sund. Cold (dark blue) water is entering the southern 
part of Öresund in a band not occupying the whole 
distance between Malmö and Köpenhamn. It passes both 
sides of Saltholm, bypasses Lommabukten on the whole. 
At Barsebäck the Öresund current is deflected to the 
north, entirely avoiding Lundakrabukten (between 
Landskrona and Barsebäck (se also Fig. 11). One could 
further notice two discharges of cooling water (bright 
blue) on the Swedish side - Fig. 8: 
at Barsebäck from a nuclear power plant directed 
almost entirely to the west 
at Landskrona from industrial processes. This 
warm water seems to flow southwards along the 
shore indicating the existance of an eddy in 
Lundakrabukten. 
During the passage of Landsat-5 dredging and dumping 
operations were going on in connection with a laying 
of a gas pipe between Köpenhamn and Malmö causing a 
lot of suspended inorganic material in the water 
visualizing streamlines. Fig. 9 shows a TM 1, 60 m 
resolution of the southern part of Öresund. Four 
sites can be seen along a line between Malmö and 
Köpenhamn acting as sources for suspended sediment. 
Traces of the sediment can be seen extending north 
wards on both sides of the island Saltholm. A dump 
ing site outside Malmö harbour can also be seen 
clearly. Fig. 10 shows a TM 1, 30 m resolution, image 
of the Swedish side clearly indicating streamlines 
- notice especially the right one which could be of 
direct interest to problem E. 
Because of the dredging operations there is a unique 
possibility of comparing flow information from water 
surface temperature differences and from suspended 
sediment. Fig. 11 shows a superposition of TM 1 and 
TM 6. The cold water is shown in dark blue whereas 
the suspended sediment is depicted as white yellow. 
The sediment trace on the Swedish side follows the 
boundary between the colder main current and warmer 
coastal water. These findings support the assumption 
that both temperature differences and suspensions 
are passive indicators of the actual flow. 
The few satellite scenes investigated thus point 
to several details of the flow structure: 
flow discharge to Kattegatt where probably both 
wind effects and the Coriolis force are important 
a kind of "curving" flow in Öresund not occupy 
ing the whole width, i.e. far from channel-like flow 
the existance of large-scale eddies along the 
southern coast of Sweden and which might advect into 
Öresund 
entrainment of colder bottom water 
large eddies in some of the bays in Öresund 
streamlines in parts of Öresund 
The satellite derived flow information could be 
compared with Fig. 1. Generally one could 
say that the former either supports the latter 
(streamlines in the southern part of Oresund and the 
tendency to an eddy in Lundakrabukten) or complements 
it. 
10* 
20* 
M* 
Figure 12. Representation of Öresund for a laterally 
integrated computational flow model (after Svensson 
1978). 
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4 NUMERICAL FLOW MODELS 
The effect on the circulation and salinity contents 
of the strait of the proposed tunnel on the bottom 
between Helsingborg and Helsingor was studied by means 
of a flow model based on the laterally integrated flow 
Figure 13. Coastal waters outside Landskrona. 
Continuous line-boundary for computational flow 
model. Dashed line-boundary for detailed computa 
tions (left). 
Computed flow in the coastal waters of Landskrona. 
Northbound flow in Oresund. 
REFERENCES 
Harremoës e 
the Swede 
Sound 19E