Ocean Science www.ocean-sci.net 1812-0784 1812-0792 6 2 2010 10.5194/os-6-573-2010 http://www.ocean-sci.net/6/573/2010/ http://www.ocean-sci.net/6/573/2010/os-6-573-2010.html http://www.ocean-sci.net/6/573/2010/os-6-573-2010.pdf 573 586 2010-06-14 Importance of the variability of hydrographic preconditioning for deep convection in the Gulf of Lion, NW Mediterranean L. Grignon laure.grignon@noc.soton.ac.uk D. A. Smeed H. L. Bryden K. Schroeder National Oceanography Centre, Southampton, UK CNR-ISMAR, Sede di La Spezia, Italy We study the variability of hydrographic preconditioning defined as the heat and salt contents in the Ligurian Sea before convection. The stratification is found to reach a maximum in the intermediate layer in December, whose causes and consequences for the interannual variability of convection are investigated. 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