FN Archimer Export Format
PT J
TI A role for icebergs in the 8.2 ka climate event
BT 
AF WIERSMA, Ane P.
   JONGMA, Jochem I.
AS 1:1,2;2:2;
FF 1:;2:;
C1 Deltares, Dept Morphol & Sedimentary Syst, NL-3584 CB Utrecht, Netherlands.
   Vrije Univ Amsterdam, Fac Earth & Life Sci, NL-1081 HV Amsterdam, Netherlands.
C2 DELTARES, NETHERLANDS
   UNIV VRIJE AMSTERDAM, NETHERLANDS
IF 3.843
TC 31
UR https://archimer.ifremer.fr/doc/00496/60749/65152.pdf
LA English
DT Article
CR IMAGES 1-MD101
   IMAGES V LEG 1-MD114
   IMAGES V LEG 4-MD114
BO Marion Dufresne
DE ;8.2 ka event;Climate modeling;Icebergs;Laurentide ice sheet;Hudson Strait;Holocene;Heinrich events
AB We investigate the potential role of icebergs in the 8.2 ka climate event, using a coupled climate model equipped with an iceberg component. First, we evaluate the effect of a large iceberg discharge originating from the decaying Laurentide ice sheet on ocean circulation, compared to a release of an identical volume of freshwater alone. Our results show that, on top of the freshwater effect, a large iceberg discharge facilitates sea-ice growth as a result of lower sea-surface temperatures induced by latent heat of melting. This causes an 8% increased sea-ice cover, 5% stronger reduction in North Atlantic Deep Water production and 1A degrees C lower temperature in Greenland. Second, we use the model to investigate the effect of a hypothetical two-stage lake drainage, which is suggested by several investigators to have triggered the 8.2 ka climate event. To account for the final collapse of the ice-dam holding the Laurentide Lakes we accompany the secondary freshwater pulse in one scenario with a fast 5-year iceberg discharge and in a second scenario with a slow 100-year iceberg discharge. Our experiments show that a two-stage lake drainage accompanied by the collapsing ice-dam could explain the anomalies observed around the 8.2 ka climate event in various climate records. In addition, they advocate a potential role for icebergs in the 8.2 ka climate event and illustrate the importance of latent heat of melting in the simulation of climate events that involve icebergs. Our two-stage lake drainage experiments provide a framework in the discussion of two-stage lake drainage and ice sheet collapse. 
PY 2010
PD AUG
SO Climate Dynamics
SN 0930-7575
PU Springer
VL 35
IS 2-3
UT 000280237900018
BP 535
EP 549
DI 10.1007/s00382-009-0645-1
ID 60749
ER

EF