Ocean Science www.ocean-sci.net 1812-0784 1812-0792 4 4 2008 10.5194/os-4-239-2008 http://www.ocean-sci.net/4/239/2008/ http://www.ocean-sci.net/4/239/2008/os-4-239-2008.html http://www.ocean-sci.net/4/239/2008/os-4-239-2008.pdf 239 246 2008-11-19 Improving the parameterisation of horizontal density gradient in one-dimensional water column models for estuarine circulation S. Blaise sebastien.blaise@uclouvain.be E. Deleersnijder Université catholique de Louvain, Unité de Génie Civil et Environnemental, Louvain-la-Neuve, Belgium Université catholique de Louvain, Centre for Systems Engineering and Applied Mechanics, Louvain-la-Neuve, Belgium A new parameterisation of horizontal density gradient for a one-dimensional water column estuarine model, inspired by the first-order finite-difference upwind scheme, is presented. This parameterisation prevents stratification from growing indefinitely, a deficiency usually referred to as "runaway stratification". 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