Abstract
THE cause of the Younger Dryas cold event, which interrupted the last deglaciation, is still a matter of debate1. A prevalent hypothesis, proposed by Broecker et al.2 is that the abrupt climate change was driven by a decrease in the rate of North Atlantic Deep Water production, triggered by a sudden dilution of North Atlantic surface water in response to the diversion of Laurentide icesheet melt water from the Mississippi drainage system to that of the St Lawrence river. Here we investigate the feasibility of this triggering mechanism by reconstructing sea-surface temperature, salinity and sea-ice cover records for the outlet of the Gulf of St Lawrence into the North Atlantic Ocean. These reconstructions—based on dinoflagellate-cyst assemblages3,4 in sediment cores from the region—show reduced meltwater runoff, low temperatures and extensive sea-ice cover during the Younger Dryas, dated here between 10,800 and 10,300 BP. Meltwater pulses did occur before and after the Younger Dryas event: as early as 11,700 BP, during the development of the Champlain Sea in the St Lawrence Lowland, and afterwards, until ~ 10,100 BP. At the resolution of our salinity proxy (0.7‰), the meltwater pulses preceding the Younger Dryas did not affect sea-surface salinity off the shelf break. These constraint on the meltwater outflow through the St Lawrence drainage system do not support the triggering mechanism of the Broecker et al. hypothesis2, unless the North Atlantic thermohaline circulation is more sensitive to small salinity changes than most models suggest23.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Zahn, R. Nature 356, 744–746 (1992).
Broecker, W. S. et al. Nature 341, 318–321 (1989).
de Vernal, A., Rochon, A., Hillaire-Marcel, C., Turon, J.-L & Guiot, J. in Proceedings of the NATO Workshop on Ice in the Climate system (ed. Peltier, W. R.) 611–621 (NATO ASI Series 112, Springer, Berlin, 1993).
de Vernal, A., Turon, J.-L. & Guiot, J. Can. J. Earth Sci. 31, 48–62 (1994).
Fairbanks, R. G. Nature 342, 637–642 (1989).
Dyke, A. S. & Prest, V. K. Géogr. phys. Quaternaire 41, 237–263 (1987).
Teller, J. T. in North America and Adjacent Oceans During the Last Deglaciation (eds Ruddiman, W. F. & Wright, H. E.) K-3, 39–69 (Geol. Soc. Am., Boulder, 1987).
Teller, J. T. & Thorleifson, L. H. in Glacial Lake Agassiz (eds Teller, J. T. & Clayton, L.) sp. paper 26, 261–307 (Geol. Assoc. Can., Ottawa, 1983).
Teller, J. T. in The late Quaternary Development of the Champlain Sea Basin (ed. Gadd, N. R.) sp. paper 35, 281–290 (Geol. Assoc. Can., Ottawa, 1988).
Broecker, W. S., Bond, G. & Klas, M. Paleoceanography 5, 469–477 (1990).
National Oceanographic Data Center World Ocean Atlas (National Oceanic and Atmospheric Administration, CD-rom data sets, Washington DC, 1994).
Koutitonsky, V. G. & Bugden, G. L. Can. J. Fish. Aquat. Sci. 113, 57–90 (1991).
Bugden, G. L. Can. J. Fish. Aquat. Sci. 113, 139–147 (1991).
Grehan, A. J., Scaps, P., Desrosiers, G., Juniper, K. & Stora, G. Vie Milieu 44, 101–107 (1994).
Wu, G. P. & Hillaire-Marcell, C. Geochim. cosmochim. Acta 58, 1303–1312 (1994).
Hillaire-Marcel, C., de Vernal, A., Bilodeau, G. & Wu, G. Can. J. Earth Sci. 31, 63–89 (1994).
de Vernal, A., Guiot, J. & Turon, J.-L. Géogr. phys. Quaternaire 47, 167–180 (1993).
de Vernal, A. & Giroux, L. Can. J. Fish. Aquat. Sci. 113, 189–199 (1991).
Anderson, T. W. in Pollen Records of Late-Quaternary North America Sediments (eds Bryant, V. M. Jr & Holloway, R. G.) 281–326 (American Association of Stratigraphic Palynologists Foundation, Dallas, 1985).
Guiot, J. Palaeogeogr. Palaeoclimatol. Palaeoecol. 80, 49–69 (1990).
Rodrigues, C. G. & Vilks, G. Quat. Sci. Rev. 13, 923–944 (1995).
Hillaire-Marcel, C. in The Late Quaternary Development of the Champlain Sea Basin (ed. Gadd, N. R.) sp. paper 35, 177–194 (Geol. Assoc. Canada, Ottawa, 1988).
Maier-Reimer, E., Mikolajewicz, U. & Haselmann, K. J. phys. Oceanogr. 23, 731–757 (1993).
Lasalle, P. & Elson, J. A. Quat. Res. 5, 621–625 (1975).
Karrow, P. F. & Occhietti, S. in Le Quaternaire du Canada et du Groenland (ed. Fulton, R. J.) 1, 341–418 (Geol. Surv. Canada, Géologie du Canada, Ottawa, 1989).
Hillaire-Marcel, C. & Occhietti, S. Zeit. Geomorph. 24, 373–392 (1980).
Bard, E. Paleoceanography 3, 635–645 (1988).
National Climate Data Center Sea Ice Climatic Atlas, NAVAIR 50-1C-541 147 (Naval Oceanography Command Detachment, Ashville, 1986).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
de Vernal, A., Hillaire-Marcel, C. & Bilodeau, G. Reduced meltwater outflow from the Laurentide ice margin during the Younger Dryas. Nature 381, 774–777 (1996). https://doi.org/10.1038/381774a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/381774a0
This article is cited by
-
Into the Holocene, anatomy of the Younger Dryas cold reversal and preboreal oscillation
Scientific Reports (2024)
-
A set of guidelines as support for the integrated geo-environmental characterization of highly contaminated coastal sites
Scientific Reports (2024)
-
Arctic drainage of Laurentide Ice Sheet meltwater throughout the past 14,700 years
Communications Earth & Environment (2022)
-
Closure of the Bering Strait caused Mid-Pleistocene Transition cooling
Nature Communications (2018)
-
Deglacial floods in the Beaufort Sea preceded Younger Dryas cooling
Nature Geoscience (2018)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.
