Water mass distribution in Fram Strait and over the Yermak Plateau in summer 1997

International audience The water mass distribution in northern Fram Strait and over the Yermak Plateau in summer 1997 is described using CTD data from two cruises in the area. The West Spitsbergen Current was found to split, one part recirculated towards the west, while the other part, on entering t...

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Bibliographic Details
Main Authors: Rudels, B., Meyer, R., Fahrbach, E., Ivanov, V. V., Østerhus, S., Quadfasel, D., Schauer, U., Tverberg, V., Woodgate, R. A.
Other Authors: Finnish Institute of Marine Research (FIMR), Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Arctic and Antarctic Research Institute (AARI), Russian Federal Service for Hydrometeorology and Environmental Monitoring (Roshydromet), Geophysical Institute Bergen (GFI / BiU), University of Bergen (UiB), Niels Bohr Institute Copenhagen (NBI), Faculty of Science Copenhagen, University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), The University Centre in Svalbard (UNIS), Applied Physics Laboratory Seattle (APL-UW), University of Washington Seattle
Format: Article in Journal/Newspaper
Language:English
Published: HAL CCSD 2000
Subjects:
Online Access:https://hal.archives-ouvertes.fr/hal-00316683
https://hal.archives-ouvertes.fr/hal-00316683/document
https://hal.archives-ouvertes.fr/hal-00316683/file/angeo-18-687-2000.pdf
Description
Summary:International audience The water mass distribution in northern Fram Strait and over the Yermak Plateau in summer 1997 is described using CTD data from two cruises in the area. The West Spitsbergen Current was found to split, one part recirculated towards the west, while the other part, on entering the Arctic Ocean separated into two branches. The main inflow of Atlantic Water followed the Svalbard continental slope eastward, while a second, narrower, branch stayed west and north of the Yermak Plateau. The water column above the southeastern flank of the Yermak Plateau was distinctly colder and less saline than the two inflow branches. Immediately west of the outer inflow branch comparatively high temperatures in the Atlantic Layer suggested that a part of the extraordinarily warm Atlantic Water, observed in the boundary current in the Eurasian Basin in the early 1990s, was now returning, within the Eurasian Basin, toward Fram Strait. The upper layer west of the Yermak Plateau was cold, deep and comparably saline, similar to what has recently been observed in the interior Eurasian Basin. Closer to the Greenland continental slope the salinity of the upper layer became much lower, and the temperature maximum of the Atlantic Layer was occasionally below 0.5 °C, indicating water masses mainly derived from the Canadian Basin. This implies that the warm pulse of Atlantic Water had not yet made a complete circuit around the Arctic Ocean. The Atlantic Water of the West Spitsbergen Current recirculating within the strait did not extend as far towards Greenland as in the 1980s, leaving a broader passage for waters from the Atlantic and intermediate layers, exiting the Arctic Ocean. A possible interpretation is that the circulation pattern alternates between a strong recirculation of the West Spitsbergen Current in the strait, and a larger exchange of Atlantic Water between the Nordic Seas and the inner parts of the Arctic Ocean.