Meltwater and ice rafting in the southern Norwegian Sea between 20 and 40 calendar kyr BP: Implications for Fennoscandian Heinrich events
|Author(s)||Lekens W. A. H.1, Sejrup H. P.1, Haflidason H.1, Knies J.2, Richter T.3|
|Affiliation(s)||1 : Univ Bergen, Dept Earth Sci, N-5007 Bergen, Norway.
2 : Geol Survey Norway, N-7491 Trondheim, Norway.
3 : Royal Netherlands Inst Sea Res, NL-1797 SZ Den Hoorn, Texel, Netherlands.
|Source||Paleoceanography (0883-8305) (Amer Geophysical Union), 2006-09 , Vol. 21 , N. 3 / PA3013 , P. 1-17|
|WOS© Times Cited||33|
|Keyword(s)||meltwater, Nordic Seas, Heinrich events|
|Abstract||[ 1] The timing of meltwater release in the southern Norwegian Sea in relation to millennial-scale climate variability is studied from core MD99-2283 based on down-core analysis of stable oxygen and carbon isotopes, calcium carbonate and ice-rafted debris (IRD). Between 20 and 40 calendar (cal) kyr B. P., strong Dansgaard-Oeschger cyclicity is expressed in increased carbonate content and reduced total organic carbon during warm interstadials and IRD marking the end of cold stadials. The planktonic delta(18)O record of core MD99-2283 compared to available isotopic records in the region confirms the existence of multisourced, synchronized meltwater anomalies during Heinrich ( H) events 2 to 4. It was found that the sudden release of meltwater occurs near major ice streams and that no significant increase in IRD was associated with the peaks of the meltwater events in the southern Norwegian Sea, suggesting meltwater discharges from ice-dammed lakes. Significant meltwater events not related to the H events were also observed between 33 and 35 cal kyr B. P., indicating that the release of meltwater is not necessarily connected with major cooling and enhanced IRD delivery. The simultaneous release of fresh water during H events in the Nordic Seas, through icebergs and ice-dammed lakes, is thought to be the result of sea level increase. The meltwater input to the Nordic Seas provides a significant additional contribution to global sea level rise associated with H3 and H4.|