 |
| Titel |
Confluence and redistribution of Atlantic water in the Nansen, Amundsen and Makarov basins |
| VerfasserIn |
U. Schauer, B. Rudels, E. P. Jones, L. G. Anderson, R. D. Muench, G. Björk, J. H. Swift, V. Ivanov, A.-M. Larsson |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
0992-7689
|
| Digitales Dokument |
URL |
| Erschienen |
In: Annales Geophysicae ; 20, no. 2 ; Nr. 20, no. 2, S.257-273 |
| Datensatznummer |
250014361
|
| Publikation (Nr.) |
 copernicus.org/angeo-20-257-2002.pdf |
|
|
|
|
|
| Zusammenfassung |
The waters in the
Eurasian Basin are conditioned by the confluence of the boundary flow of warm,
saline Fram Strait water and cold low salinity water from the Barents Sea
entering through the St. Anna Trough. Hydrographic sections obtained from RV
Polarstern during the summer of 1996 (ACSYS 96) across the St. Anna Trough and
the Voronin Trough in the northern Kara Sea and across the Nansen, Amundsen and
Makarov basins allow for the determination of the water mass properties of the
two components and the construction of a qualitative picture of the circulation
both within the Eurasian Basin and towards the Canadian Basin. At the
confluence north of the Kara Sea, the Fram Strait branch is displaced from the
upper to the lower slope and it forms a sharp front to the Barents Sea water at
depths between 100 m and greater than 1000 m. This front disintegrates
downstream along the basin margin and the two components are largely mixed
before the boundary current reaches the Lomonosov Ridge. Away from the
continental slope, the presence of interleaving structures coherent over wide
distances is consistent with low lateral shear. The return flow along the
Nansen Gakkel Ridge, if present at all, seems to be slow and the cold water
below a deep mixed layer there indicates that the Fram Strait Atlantic water
was not covered with a halocline for about a decade. Anomalous water mass
properties in the interior of the Eurasian Basin can be attributed to isolated
lenses rather than to baroclinic flow cores. Eddies have probably detached from
the front at the confluence and migrated into the interior of the basin. One
deep (2500 m) lens of Canadian Basin water, with an anticyclonic eddy
signature, must have spilled through a gap of the Lomonosov Ridge. During ACSYS
96, no clear fronts between Eurasian and Canadian intermediate waters, such as
those observed further north in 1991 and 1994, were found at the Siberian side
of the Lomonosov Ridge. This indicates that the Eurasian Basin waters enter the
Canadian Basin not only along the continental slope but they may also cross the
Lomonosov Ridge at other topographic irregularities. A decrease in salinity
around 1000 m in depth in the Amundsen Basin probably originates from a larger
input of fresh water to the Barents Sea. The inherent density changes may
affect the flow towards the Canadian Basin.
Key words. Oceanography: general
(Artic and Antartic oceanography; descriptive and regional oceanography)
Oceanography: physical (hydrography) |
| |
|
| Teil von |
|
|
|
|
|
|
|
|