Mechanisms of Antarctic katabatic currents near Terra Nova Bay

The evolution of Antarctic katabatic wind in the vicinity of Terra Nova Bay has been studied using a three dimensional, hydrostatic, limited area model. Realistic simulations of a summer katabatic event, using different horizontal resolutions, have been performed by employing a sequential self-nesting procedure. The high resolution orography data allow a description of the structure of the main valleys and of the two different flows 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 means of a Lagrangian diagnostic study performed along trajectories flowing down from the above mentioned glaciers. Heat balance and kinetic energy balance have been evaluated accurately in order to asses the characteristics of the two katabatic currents that may superpose once they reach the Nansen Ice Sheet.