32 | 
Cruise Report, RV ATAIR, Cruise 0671021-1, Bremerhaven - Thyboron —- Aberdeen, 18 Jul - 10 Aug 2023 
Bottom temperatures (Figure 6.4, left) are generally warmer south of 55°N, on the Dogger 
Bank and off the continental coasts compared to the central to northern North Sea due to 
shallower water depths. Bottom temperatures >18°C stretch along the Belgian, Dutch and Ger- 
man coast up to Denmark. The coldest bottom temperatures (< 8°C) are located in the Norwe- 
gian Trench or cover larger bottom areas of the central to northern North Sea (-56°-60°N, 0°- 
5°E). Bottom temperatures > 10°C stretch band-like along the eastern British coast from the 
Shetland Islands to 56°N. 
Salinitv at 5 dbar 
50°N 
58° 
56° 
BA" 
592° 
50° => 
6°W Ad° 
2° 9° 
9° 
Salinity at 5 dbar minus mean (2000-2020) 
60°N 
59° 
B6° 
54° - 
“\Atair 
06710127-1 
8u_:- 10 Aug 2023 
Aremerhaven - Aberde 
52° 
XV Atair 
7ruise 06710121-1 
18 Juf - 10 Aug 2023 
Bremerhaven - Aberdeer. 
. 2 50° fs = 
4° 6° 8° 10°E 6°W 4° 
9 
a 
50 
4° 
— FF 
6° 8° 10°E 
Figure 6.5. CTD-derived spatial distribution for the salinity near the surface in summer 2023 (left) and 
respective salinity deviations (right) from a long-term mean, 20 years, comprising NSSS cruises of the 
years 2000-2020 (except 2019). 
In summer 2023, CTD-derived near-surface salinity > 35 was observed to appear in two sep- 
arate patches (Figure 6.5, left). The larger patch was notable to the southeast of the Shetland 
Islands near 60°N and 59°N, with some saline signals appearing at 58°N. Due limited data 
available for the 59°N latitude in 2023, the connectivity between the Atlantic inflow near the 
Shetland Islands and spreading south until 58°N is less clear this year. The second patch, 
isolated from the northern patch, stretches across along -4°E between 57°N and 56°N. The 
isohaline 34.5 formed a horseshoe pattern from about 57°N off the British coast to 54°N south 
of the Dogger Bank until 60°N, 4°E in the north of the North Sea. Near-surface water inside 
this horse-shoe shows salinities ranging from>= 34.5 to 35.2 with the highest values observed 
south of Shetland and along 59°N and 60°N. Coastal salinities off the eastern British coast fall 
well below 34.5 in a band-like pattern between -57°N and the English Channel. Coastal salin- 
ities on the continental side of the North Sea show a local minimum near and north of the Rhine 
delta (S < 33) and off the North Frisian German and Danish coasts (S < 32). The Norwegian 
Trench shows the fresh Baltic outflow close to the Norwegian coast with salinity mostly < 32