Mechanisms of Antarctic katabatic currents near Terra Nova Bay

The evolution of Antarctic katabatic wind in the vicinity of Terra Nova Bayhas been studied using a three dimensional, hydrostatic, limited area model. Realistic simulations of a summer katabatic event, using differenthorizontal resolutions, have been performed by employing a sequentialself-nesting procedure. The high resolution orography data allow adescription of the structure of the main valleys and of the two differentflows descending from the broad Reeves Glacier and (with less accuracy)channelled into the much narrower Priestley Glacier valley, respectively.The mechanism of katabatic wind development has been investigated by meansof a Lagrangian diagnostic study performed along trajectories flowing downfrom the above mentioned glaciers. Heat balance and kinetic energy balancehave been evaluated accurately in order to asses the characteristics of thetwo katabatic currents that may superpose once they reach the Nansen Ice Sheet.