Publikationsdatum:
2017-06-23
Beschreibung:
Dinoflagellate cysts have been investigated in surface
from the Norwegian-Greenland Sea and short sediment cores
Norwegian Sea spanning the last 15,000 years.
sediments
from the
The distribution of single species and assemblages is related to
the bathymetry and oceanography of the Norwegian-Greenland Sea.
Oceanographic fronts can be recognized in the distribution of species
and assemblages.
Round protoperidinoid cysts, MuZtispinuZa minuta s.l. and HaZodinium
spp., characterize the assemblages from the East Greenland Shelf.
Nematosphaeropsis Zabyrinthus and ?Impagidinium paZZidum dominate the
assemblages in the central leeland and Greenland Seas. Operculodinium
centrocarpum is important in the marginal area of the Arctic domain
and dominates clearly the assemblages from the Norwegian Sea. Assernblages
from the shelf of north leeland are marked by cysts of
Peridinium faeroense.
The distribution pattern of single species and assemblages reveals
that relatively warm north Atlantic waters only pass through the
Faeroe Shetland Canal into the Norwegian-Greenland Sea and further · up
into the eastern Arctic Ocean and the Barents Sea. In the southern
Norwegian Sea the Atlantic water masses are already modified by
advection of surface waters from the North Sea.
The development of the Norwegian current has been reconstructed by
means of dinoflagellate cysts since termination r •. North Atlantic
water masses have almost always influenced the surface water masses in
the last 15,000 years. Since ca. 12,000 to 13,000 BP, the influence of
warmer North Atlantic waters increased significantly in the NorwegianGreenland
Sea. The modern circulation system was established around
10,000 BP. First, the Norwegian current was cooler and less saline,
and then obtained its modern hydrographic properties around 6,000 to
7,000 BP. A slight change towards cooler conditions is documented in
the western marginal areas in the last 2,000 to 3,000 years.
Changes in the oceanography of the Norwegian-Greenland Sea must be
related to modifications in the water masses and the circulation
system of the entire North Atlantic. The discontinous influx of
meltwater may have been an important factor for changes in the
oceanography and the ecological conditions.
Materialart:
Thesis
,
NonPeerReviewed
Format:
text
DOI:
10.3289/GEOMAR_REP_7_1991
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