UNIVERSITE TOULOUSE III - PAUL SABATIER Ecole ... - LEGOS

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2. Hydrological context, sampling, analytical procedures
The Nordic Seas refer to the seas lying between Greenland and Norway: the Norwegian,
the Greenland and the Iceland Seas (Fig. 1). Their deep openings with the oceans are the Fram
Strait in the north, the Denmark Strait in the southwest and the Faroe Shetland Channel in the
southeast. Their main hydrological structures are: 1) an eastern boundary current, the
Norwegian Atlantic Current followed by the West Spitsbergen Current, bringing warm and
saline Atlantic Water to the north, 2) a western boundary current, the East Greenland Current
(EGC), carrying waters from the Fram Strait, through the Greenland and Iceland Seas,
towards the Denmark Strait, 3) three cyclonic gyres in the Greenland, Iceland and Norwegian
Seas (Fig. 1; Poulain and Warn-Varnas, 1996; Hansen and Østerhus, 2000).
Figure 1.
Studied area. The large black arrows represent the main hydrodynamic structures: the
East Greenland Current, the Greenland Sea and Iceland Sea gyres. Hydrological sections are
indicated by black white-edged segments. The dashed lines bordering the coasts indicate their
geological type. The white black-striped lines indicate Precambrian formations (ε Nd around –
35), whereas the black white-striped ones indicate basaltic ones (ε Nd around +8). Note the
basaltic nature of the formations bordering the Denmark Strait.
The East Greenland Current flows parallel to the isobaths. It extends from the
continental shelf beyond the bottom of the slope, around 3000 m depth. Its annual mean
transport is 21 ± 3 Sv (1 Sv = 10 6 m 3 .s -1 ; Woodgate et al., 1999). It carries waters of different
origins, some come from the Arctic Ocean, some from the Atlantic Ocean by way of the
Norwegian Atlantic Current and the West Spitsbergen Current, and some from the Greenland
and Iceland gyres (Rudels et al., 1999b).
Seawater samples were collected along four sections within the EGC, above the slope,
between the Fram and Denmark Straits (Fig. 1). A station was also carried out at the mouth of
the Nansen Fjord, in the northwest of Denmark Strait.
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