Climate Dynamics

, Volume 35, Issue 7, pp 1361–1371

Sea ice induced changes in ocean circulation during the Eemian

  • Andreas Born
  • Kerim H. Nisancioglu
  • Pascale Braconnot
Article

DOI: 10.1007/s00382-009-0709-2

Cite this article as:
Born, A., Nisancioglu, K.H. & Braconnot, P. Clim Dyn (2010) 35: 1361. doi:10.1007/s00382-009-0709-2

Abstract

We argue that Arctic sea ice played an important role during early stages of the last glacial inception. Two simulations of the Institut Pierre Simon Laplace coupled model 4 are analyzed, one for the time of maximum high latitude summer insolation during the last interglacial, the Eemian, and a second one for the subsequent summer insolation minimum, at the last glacial inception. During the inception, increased Arctic freshwater export by sea ice shuts down Labrador Sea convection and weakens overturning circulation and oceanic heat transport by 27 and 15%, respectively. A positive feedback of the Atlantic subpolar gyre enhances the initial freshening by sea ice. The reorganization of the subpolar surface circulation, however, makes the Atlantic inflow more saline and thereby maintains deep convection in the Nordic Seas. These results highlight the importance of an accurate representation of dynamic sea ice for the study of past and future climate changes.

Keywords

Sea iceOcean circulationEemianGlacial inceptionSubpolar gyreNorth Atlantic

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Andreas Born
    • 1
    • 2
  • Kerim H. Nisancioglu
    • 1
  • Pascale Braconnot
    • 3
  1. 1.Bjerknes Centre for Climate ResearchBergenNorway
  2. 2.Geophysical InstituteUniversity of BergenBergenNorway
  3. 3.IPSL/LSCE, Unité mixte CEA-CNRS-UVSQGif sur YvetteFrance