HR: 0830h
AN: OS21B-1120    [PDF]
TI: The not so ice-free Norwegian sea, and its Connection to the Arctic Ocean
AU: * Bischof, J F
EM: jbischof@odu.edu
AU: Darby, D A
EM: ddarby@odu.edu
AB: The Norwegian Sea is usually considered ice-free year round. It thus came as a surprise that Holocene pelagic sediments more than 700 km south of the maximum ice margin and 400 km from the nearest land contained in part large quantities of coarse, ice rafted rock and mineral fragments. The quantities of these grains drop from an early Holocene maximum to a mid-Holocene minimum, corresponding to a powerful Norwegian Current, and then rise again to the present. The composition of these grains is incompatible with a derivation from Norway or Iceland, and is also profoundly different from debris deposited by the East Greenland Current. The presence and type of coal places its origin to either the East Siberian Islands or to NW Alaska. In either case, the grains document a strong, periodic southward extension of the Transpolar Drift. Cores from the western Arctic Ocean replicate this pattern in an opposite sense, from an early Holocene low to a mid-Holocene high and back. Superimposed on this long-term dynamic are shorter directional changes at ca. 1000 year spacing, documented by highs and lows in the abundance of chert. The Arctic ice intrusions into the Norwegian Sea most likely occur on much shorter time scales, perhaps on the order of only a few decades.
DE: 1610 Atmosphere (0315, 0325)
DE: 1620 Climate dynamics (3309)
DE: 1635 Oceans (4203)
DE: 3344 Paleoclimatology
DE: 3349 Polar meteorology
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting