Convection in the Western North Atlantic Sub-Polar Gyre: Do Small-Scale Wind Events Matter?

  • Robert S. Pickart
  • Kjetil Våge
  • G. W. K. Moore
  • Ian A. Renfrew
  • Mads Hvid Ribergaard
  • Huw C. Davies

In 1912, the polar explorer and scientist Fridtjof Nansen published an article entitled “Bottom Water and the Cooling of the Ocean”, in which he discussed the origin of the deep water in the North Atlantic south of the Greenland–Scotland Ridge (Nansen 1912). It was known at the time that dense water spills over the ridge system, both through Denmark Strait and between Iceland and the Faroes. Nansen argued, however, that these sources were insufficient to ventilate the vast body of deep water in the North Atlantic basin. He postulated, therefore, that open-ocean convection must be occurring south of the ridge. Furthermore, he suspected that this process was taking place in the Irminger Sea, east of Greenland. He noted that the cyclonic circulation in the Irminger basin (originally documented by Knudsen 1899) would help keep restratifying waters at the fringes, and that the center of the gyre, where the circulation was weak, would be conducive for deep convection.


North Atlantic Oscillation Deep Convection North Atlantic Oscillation Index Physical Oceanography World Ocean Circulation Experiment 
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Copyright information

© Springer Science + Business Media B.V 2008

Authors and Affiliations

  • Robert S. Pickart
    • 1
  • Kjetil Våge
    • 1
  • G. W. K. Moore
    • 2
  • Ian A. Renfrew
    • 3
  • Mads Hvid Ribergaard
    • 4
  • Huw C. Davies
    • 5
  1. 1.Woods Hole Oceanographic InstitutionWoods HoleUSA
  2. 2.University of TorontoTorontoCanada
  3. 3.University of East AngliaUK
  4. 4.Danish Meteorological InstituteDenmark
  5. 5.Swiss Federal Institute of TechnologySwitzerland

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