The simulation of the katabatic wind events in the polar regions is currently done with hydrostatic mesoscale meteorological models. Due to the big difference of level and to the sometimes violent nature of these winds, it is supposed that this hydrostatic assumption cannot always be valid. Also the phenomenon of hydraulic jump (Loewe phenomenon) frequently observed in katabatic winds cannot be represented correctly without a non-hydrostatic model.
The aim of the extension of the project is to develop in common with the IAP team a non hydrostatic version of the model and also take their experience in the parametrization of the infra-red and visible radiation fields. There are thus two parts in the extention: 1.Development of a non-hydrostatic compressible meso-scale model to be used for the simulation of the flow over the topography of the polar ice-caps. This is to take into account complex terrain features involving important vertical accelerations that are not represented with hydrostatic models. IAP (prague) has an
incompressible non-hydrostatic model and thus has some experience in this field. UCL and UPS have both a compressible but
hydrostatic model already used in the project.
2.Improvement of radiation codes in meso-model. IAP has been developing radiation codes and parametrization for cloudiness, aerosols, water vapour and C02. UCL and UPS have efficient and accurate parametrization for water vapour, C02 and clouds. The three teams can join their experience and hopely produce a set of parametrizations improving the representation of high latitude radiation fields.