Séminaire
Theories of topographic instability predict growth of perturbations of mean flow and wave modes due to their interaction with mountains under favorable conditions. Greenland is selected as a testbed be-cause of its isolation, simple shape and appropriate size. The observed flow development during mountain torque events is investigated in terms of a regression analysis where the torques serve as indicators of this interaction. Changes of axial angular momentum and the zonal mean wind with respect to the torques are monitored for Greenland domains. It is found that the response of the zonal winds to the torques is quite small and not systematic. There is no evidence of topographic instability. Reasons for this negative outcome are discussed as are shortcomings of the tests.
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