First preliminary results 
In contrast to 2006 where a hot July had a strong imprint on the oceanographic summer 
maximum conditions cool and windy weather conditions during the second quarter of the 
year 2007 prevented the situation from a further temperature increase. 
In the surface layer (2-15 m) temperature was about 2,5© lower than in the preceding year 
but still well above the long-term average. 
The average temperature above bottom in the shallow and fully mixed southern North Sea 
was at 16,5©, Le. about 0.5 © below SST. In the southern part of the Central North Sea 
temperatures in the depth range of 15 — 50 m were at their maximum (55 N: 15©C)since the 
start of the summer cruises in 1998. Between 56 - 60 N the temperature in this depth range 
remains since years nearly constant at 11,7%. Bel ow the thermocline the water temperature 
between 56 — 60 N was at 8.5© which is 0.5© highe r than last year but in the range of the 
foregoing years. The relatively warm water in 2007 just above the thermocline is probably 
due to deeper mixing of warmer surface water in late spring or early summer. Vertical tem- 
perature sections from the towed Delphin system are presented in Fig. 2a. Spatial surface 
and bottom temperature distributions are presented in Fig. 3a. 
The salinity conditions in the surface water is best characterised by the course of the 34 iso- 
haline in the eastern part of the North Sea. In 2007 a broad rim of lower salinity water ex- 
tended from the Dutch coast at 6 E to 7 E at Ringkobing Fjord (56 N, Jutland) and then to 2 
E at 60 N. This is because of the higher river runoff in mid and eastern Europe and subse- 
quently a stronger discharge of Baltic Sea low salinity water into the Norwegian coastal cur- 
rent. There was no major change in the salinity distribution of the deeper North Sea. Vertical 
salinity sections from the towed Delphin system are presented in Fig. 2b. Spatial surface and 
bottom salinity distributions are presented in Fig. 3a. 
Due to the good mixing conditions the oxygen saturation in the southern North Sea and 
above the thermocline in the central and northern North Sea was slightly above 100 %. Be- 
‚ow the thermocline oxygen saturation ranged between 80 and 90 %. It is worth mentioning 
nearly persistant appearance of a relative oxygen depression west of Ringkebing Fjord (56 
N, Jutland) at 6 E. Vertical oxygen saturation sections from water samples are presented in 
Fig. 2c. Spatial surface and bottom oxygen saturation distributions are presented in Fig. 3c. 
15