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Summary: A deep-sea coral record of North Atlantic radiocarbon through the
Younger Dryas: Evidence for intermediate water/deepwater
reorganization
Selene F. Eltgroth,1
Jess F. Adkins,1
Laura F. Robinson,1
John Southon,2
and Michaele Kashgarian3
Received 12 July 2005; revised 25 May 2006; accepted 28 June 2006; published 17 November 2006.
[1] Our record of Younger Dryas intermediate-depth seawater D14
C from North Atlantic deep-sea corals
supports a link between abrupt climate change and intermediate ocean variability. Our data show that northern
source intermediate water ($1700 m) was partially replaced by 14
C-depleted southern source water at the onset
of the event, consistent with a reduction in the rate of North Atlantic Deep Water formation. This transition
requires the existence of large, mobile gradients of D14
C in the ocean during the Younger Dryas. The D14
C
water column profile from Keigwin (2004) provides direct evidence for the presence of one such gradient at the
beginning of the Younger Dryas ($12.9 ka), with a 100% offset between shallow (<$2400 m) and deep water.
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