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MAR model

The MAR (Modèle Atmosphérique Régional) model is a regional climate model originally developed to study the Polar Regions (Fettweis et al., 2013). It has been chosen as reference for downscaling future projections over Greenland in the last IPCC report (AR5), but has recently been adapted with success to the Belgian climate (Wyard et al., 2016). MAR uses the hydrostatic hypothesis and is fully coupled to the 1-D Surface Vegetation Atmosphere Transfer scheme SISVAT (Soil Ice Snow Vegetation Atmosphere Transfer). The atmospheric part of MAR is fully described in Gallée and Schayes (1994), while the SISVAT scheme is detailed in De Ridder and Gallée (1998). The representation of the hydrological cycle includes a cloud microphysical model, with conservation equations for cloud droplet, raindrop, cloud ice crystal, and snow flake concentrations. Solar and infrared radiation schemes from ERA-40 are used. The convective adjustment scheme comes from Bechtold et al. (2001). The vegetation is described through its plant type which enables to infer the parameter values: the displacement height, the roughness length for momentum, the root fraction, the minimum stomatal resistance, and the global plant resistance. The soil hydrodynamic characteristics (four parameters) are constant along the soil profile.