Evidence of interactions between shorter scale gravity waves and tides is presented using sodium resonance lidar data obtained from the STARFIRE optical range. This data set makes available a complete set of measurements of sodium density, temperature and three components of the wind for five nights - 2,3 February and 1,2,4 April 1995. On all five nights, spanning two different seasons, similar signatures are seen which will be interpreted as evidence for the filtering of gravity waves by the longer period tide. This conjecture is supported by the presence of regions of unstable Richardson number at the same altitude as the smaller scale wave motions seem to disappear. Other supporting evidence in the form of the frequency spectrum calculated at each height as well as hodographic analysis will be presented as well. The implications of these results for the global momentum and heat budget will be estimated from the data, piecing together a coherent picture of actual mesosheric gravity-wave events.
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12th Conference on Atmospheric and Oceanic Fluid Dynamics