J1.8
Climatology of the air-sea interaction associated with high wind events near Cape Farewell Greenland
Wataru Yanase, University of Tokyo, Tokyo, Japan; and G. W. K. Moore
High wind events that occur Cape Farewell Greenland are of interest as a result of the significant hazard they represent to maritime activity as well as their potential role in forcing deep ocean convection in the region. In this paper, the NCEP reanalysis is used to develop climatology of high wind speed events near Cape Farewell Greenland. In addition to the previously identified ‘tip jet’ events that are characterized by strong westerly flow, we show that there also exist ‘reverse tip jet’ events that are characterized by strong easterly flow. Both types of events are associated with deep extra-tropical cyclones that are undergoing an interaction with the high topography of southern Greenland. The track of the cyclones across the North Atlantic that result in these 2 classes of high wind speed events are very different with tip jets being associated with a northeasterly track, while reverse tip jets being associated with a more easterly track. We also show that the frequency of both types of events is highest in the winter months and is modulated by the phase of the North Atlantic Oscillation (NAO). We show that the air-sea fluxes associated with these two classes of high wind speed events are dramatically different with tip jets resulting in an increase in the loss of ocean buoyancy, compared to mean conditions, with reverse tip jets having the opposite effect.
Joint Session 1, Polar Coastal Processes (Joint with Sixth Conference on Coastal Atmospheric and Oceanic Prediction and Processes and the 8th Conf on Polar Meteorology and Oceanography)
Monday, 10 January 2005, 8:55 AM-5:45 PM
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