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PALEOCEANOGRAPHY,
VOL. 18, NO. 2,
1044,
doi:10.1029/2001PA000654,
2003
Late Holocene surface ocean conditions of the Norwegian Sea (Vøring Plateau)
Carin Andersson
Bjerknes Centre for Climate Research, University of Bergen, Bergen, Norway
Bjørg Risebrobakken
Department of Earth Science, University of Bergen, Bergen, Norway
Eystein Jansen
Bjerknes Centre for Climate Research, University of Bergen, Bergen, Norway Department of Earth Science, University of Bergen, Bergen, Norway Nansen Environmental and Remote Sensing Center (NERSC), Bergen, Norway
Svein Olaf Dahl
Department of Geography, University of Bergen, Bergen, Norway
Abstract
Late Holocene sea surface ocean conditions of the eastern Norwegian Sea (Vøring Plateau) are inferred from planktic stable
isotopes and planktic foraminiferal assemblage changes in cores JM97-948/2A and MD95-2011 (66.97°N, 7.64°E). Strong covariance
between the planktic stable oxygen isotopic record and abundance changes of N. pachyderma (sin) show that major changes in surface ocean conditions are reflected both in the geochemical composition of the foraminiferal
tests as well as in the composition of the foraminiferal fauna. Surface ocean conditions warmer than present were common during
the past 3000 years. During the so-called Medieval Warm Period, surface conditions were highly variable with marked changes
in sea surface temperature. The warmest sea surface temperatures during this period occurred between 800 and 550 years BP
(0 BP = AD 2000). Climatic deterioration, recorded as decreases in sea surface temperature, occurred at about 2750, 1550,
400, and 100 years BP. The cooling events at about 2750 and 1550 years BP appear to correlate with increases in ice-rafted
debris in the North Atlantic. Based on the results from JM97-948/2A and MD95-2011, the onset of the Little Ice Age cooling
trend seems to have occurred around 700–600 years BP. Faunal changes indicate two cooling events during the Little Ice Age
(at 400 and 100 years BP) that correspond to decreases in Fennoscandian summer temperatures and increases in ice-rafted debris
in the eastern North Atlantic.
Received 10
May
2001;
accepted 26
February
2003;
published 4
June
2003.
Index Terms: 3030 Marine Geology and Geophysics: Micropaleontology; 4267 Oceanography: General: Paleoceanography; 4870 Oceanography: Biological and Chemical: Stable isotopes.
Subscriber Access to Full Article (Nonsubscribers may purchase for $9.00, Includes print PDF, file size: 869547 bytes)
Citation: Andersson, C., B. Risebrobakken, E. Jansen, and S. O. Dahl
(2003),
Late Holocene surface ocean conditions of the Norwegian Sea (Vøring Plateau),
Paleoceanography,
18(2),
1044,
doi:10.1029/2001PA000654.
Copyright 2003 by the American Geophysical Union.
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