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Deglacial surface circulation changes in the northeastern Atlantic: Temperature and salinity records off NW Scotland on a century scale

1997; American Geophysical Union; Volume: 12; Issue: 6 Linguagem: Inglês

10.1029/97pa02289

1944-9186

D. Kroon, William E. N. Austin, Mark R Chapman, G.M. Ganssen,

Geological formations and processes

Sea surface temperature and salinity estimates reconstructed from a core collected on the Barra Fan, northwest Scotland (56°43′N, 09°19′W; water depth 1320 m), show a series of rapid oscillations during the last deglacial period that are very similar to those observed in the δ 18 O records from Greenland ice cores. These records indicate that the transport of heat and salt toward the Nordic Seas was highest during the Bølling period. This “superconveyor” weakened after the Bølling, probably as a consequence of increased meltwater flux reducing the oceanic salt content, as suggested by the Barbados sea‐level record. Evidence for a phase of ice rafting during the Allerød is presented for the first time from this latitude in the northeast Atlantic. The Younger Dryas stadial, resolved here at a century/decadal scale, is characterized by very rapid oscillations in temperature and salinity, indicating that warm, relatively saline waters repeatedly displaced cool polar waters at this latitude. These observations attest to the inherent instability of the deglacial climate system.