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Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka : Volume 9, Issue 2 (10/04/2013)

By Morrill, C.

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Book Id: WPLBN0004006634
Format Type: PDF Article :
File Size: Pages 14
Reproduction Date: 2015

Title: Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka : Volume 9, Issue 2 (10/04/2013)  
Author: Morrill, C.
Volume: Vol. 9, Issue 2
Language: English
Subject: Science, Climate, Past
Collections: Periodicals: Journal and Magazine Collection (Contemporary), Copernicus GmbH
Publication Date:
Publisher: Copernicus Gmbh, Göttingen, Germany
Member Page: Copernicus Publications


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Bakker, P., Otto-Bliesner, B. L., Renssen, H., Morrill, C., & Legrande, A. N. (2013). Model Sensitivity to North Atlantic Freshwater Forcing at 8.2 Ka : Volume 9, Issue 2 (10/04/2013). Retrieved from

Description: Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA. We compared four simulations of the 8.2 ka event to assess climate model sensitivity and skill in responding to North Atlantic freshwater perturbations. All of the simulations used the same freshwater forcing, 2.5 Sv for one year, applied to either the Hudson Bay (northeastern Canada) or Labrador Sea (between Canada's Labrador coast and Greenland). This freshwater pulse induced a decadal-mean slowdown of 10–25% in the Atlantic Meridional Overturning Circulation (AMOC) of the models and caused a large-scale pattern of climate anomalies that matched proxy evidence for cooling in the Northern Hemisphere and a southward shift of the Intertropical Convergence Zone. The multi-model ensemble generated temperature anomalies that were just half as large as those from quantitative proxy reconstructions, however. Also, the duration of AMOC and climate anomalies in three of the simulations was only several decades, significantly shorter than the duration of ~150 yr in the paleoclimate record. Possible reasons for these discrepancies include incorrect representation of the early Holocene climate and ocean state in the North Atlantic and uncertainties in the freshwater forcing estimates.

Model sensitivity to North Atlantic freshwater forcing at 8.2 ka

Thomas, E. R., Wolff, E. W., Mulvaney, R., Steffensen, J. P., Johnsen, S. J., Arrowsmith, C., White, J. W. C., Vaughn, B., and Popp, T.: The 8.2 ka event from Greenland ice cores, Quaternary Sci. Rev., 26, 70–81, 2007.; Thornalley, D. J. R., Elderfield, H., and McCave, I. N.: Holocene oscillations in temperature and salinity of the surface subpolar North Atlantic, Nature, 457, 711–714, 2009.; Timmermann, A., An, S.-I., Krebs, U., and Goosse, H.: ENSO suppression due to weakening of the North Atlantic thermohaline circulation, J. Climate, 18, 3122–3139, 2005.; Tornqvist, T. E. and Hijma, M. P.: Links between early Holocene ice-sheet decay, sea-level rise and abrupt climate change, Nat. Geosci., 5, 601–606, 2012.; Vellinga, M. and Wood, R. A.: Global climatic impacts of a collapse of the Atlantic thermohaline circulation, Climatic Change, 54, 251–267, 2002.; Veski, S., Seppä, H., and Ojala, A. E. K.: Cold event at 8200 yr BP recorded in annually laminated lake sediments in eastern Europe, Geology, 32, 681–684, 2004.; von Grafenstein, U., Erlenkeuser, H., Muller, J., Jouzel, J., and Johnsen, S.: The cold event 8200 years ago documented in oxygen isotope records of precipitation in Europe and Greenland, Clim. Dynam., 14, 73–81, 1998.; Wagner, A. J., Morrill, C., Otto-Bliesner, B. L., Rosenbloom, N., and Watkins, K. R.: Model support for forcing of the 8.2 ka event by meltwater from the Hudson Bay ice dome, Clim. Dynam., doi:10.1007/s00382-013-1706-z, online first, 2013.; Wiersma, A. P. and Jongma, J. I.: A role for icebergs in the 8.2 ka climate event, Clim. Dynam., 35, 535–549, 2010.; Wunsch, C.: Towards understanding the Paleocean, Quaternary Sci. Rev., 29, 1960–1967, 2010.; Wiersma, A. P., Renssen, H., Goosse, H., and Fichefet, T.: Evaluation of different freshwater forcing scenarios for the 8.2 ka BP event in a coupled climate model, Clim. Dynam., 27, 831–849, 2006.; Winsor, K., Carlson, A. E., Klinkhammer, G. P., Stoner, J. S., and Hatfield, R. G.: Evolution of the northeast Labrador Sea during the last interglaciation, Geochem. Geophys. Geosys., 13, Q11006, doi:10.1029/2012GC004263, 2012.; Yin, J., Stouffer, R. J., Spelman, M. J., and Griffies, S. M.: Evaluating the uncertainty induced by the virtual salt flux assumption in climate simulations and future projections, J. Climate, 23, 80–96, 2009.; Zhang, R. and Delworth, T. L.: Impact of Atlantic multidecadal oscillations on India/Sahel rainfall and Atlantic hurricanes, Geophys. Res. Lett., 33, L17712, doi:10.1029/2006GL026267, 2006.; Adkins, J. F., McIntyre, K., and Schrag, D. P.: The salinity, temperature, and δ18O of the glacial deep ocean, Science, 298, 1769–1773, 2002.; Barber, D. C., Dyke, A., Hillaire-Marcel, C., Jennings, A. E., Andrews, J. T., Kerwin, M. W., Bilodeau, G., McNeely, R., Southon, J., Morehead, M. D., and Gagnon, J.-M.: Forcing of the cold event of 8,200 years ago by catastrophic drainage of Laurentide lakes, Nature, 400, 344–348, 1999.; Berger, A. L.: Long-term variations of caloric insolation resulting from the Earth's orbital elements, Quaternary Res., 9, 139–167, 1978.; Bianchi, G. G. and McCave, I. N.: Holocene periodicity in North Atlantic climate and deep-ocean flow south of Iceland, Nature, 397, 515–517, 1999.; Born, A. and Levermann, A.: The 8.2 ka event: Abrupt transition of the subpolar gyre toward a modern North Atlantic circulation, Geochem. Geophys. Geosys., 11, Q06011, doi:10.1029/2009GC003024, 2010.; Came, R. E., Oppo, D. W., and McManus, J. F.: Amplitude and timing of temperature and salinity variability in the subpolar North Atlantic over the past 10 k.y., Geology, 35, 315–318, 2007.; Häkkinen, S. and Rhines, P. B.: Decline of subpolar North Atlantic circulatio


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