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| Titel |
Water mass evolution of the Greenland Sea since late glacial times |
| VerfasserIn |
M. M. Telesiński, R. F. Spielhagen, H. A. Bauch |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1814-9324
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| Digitales Dokument |
URL |
| Erschienen |
In: Climate of the Past ; 10, no. 1 ; Nr. 10, no. 1 (2014-01-16), S.123-136 |
| Datensatznummer |
250116899
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| Publikation (Nr.) |
 copernicus.org/cp-10-123-2014.pdf |
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| Zusammenfassung |
| Four sediment cores from the central and northern Greenland Sea basin, a
crucial area for the renewal of North Atlantic deep water, were analyzed for
planktic foraminiferal fauna, planktic and benthic stable oxygen and carbon
isotopes as well as ice-rafted debris to reconstruct the environmental
variability in the last 23 kyr. During the Last Glacial Maximum, the
Greenland Sea was dominated by cold and sea-ice bearing surface water
masses. Meltwater discharges from the surrounding ice sheets affected the
area during the deglaciation, influencing the water mass circulation. During
the Younger Dryas interval the last major freshwater event occurred in the
region. The onset of the Holocene interglacial was marked by an increase in
the advection of Atlantic Water and a rise in sea surface temperatures
(SST). Although the thermal maximum was not reached simultaneously across
the basin, benthic isotope data indicate that the rate of overturning
circulation reached a maximum in the central Greenland Sea around 7 ka.
After 6–5 ka a SST cooling and increasing sea-ice cover is noted. Conditions
during this so-called "Neoglacial" cooling, however, changed after 3 ka,
probably due to enhanced sea-ice expansion, which limited the deep
convection. As a result, a well stratified upper water column amplified the
warming of the subsurface waters in the central Greenland Sea, which were fed
by increased inflow of Atlantic Water from the eastern Nordic Seas. Our data
reveal that the Holocene oceanographic conditions in the Greenland Sea did
not develop uniformly. These variations were a response to a complex
interplay between the Atlantic and Polar water masses, the rate of sea-ice
formation and melting and its effect on vertical convection intensity during
times of Northern Hemisphere insolation changes. |
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