| Summary: | Filament intrusions are observed in high-resolutiontemperature (T) measurements from a 100-m and severalmonth-long mooring in the Fram Strait in around 400-m waterdepth at the continental slope West of Svalbard (Spitsbergen,Norway). In this dynamic environment, a wide variety of intrusivelayers are observed with thicknesses between 5 and80 m with warmer water between cooler waters above andbelow. The layers typically last from several hours up to1 day, exceeding the local buoyancy period but not lastingas long as intrusive layers in the open ocean. The intrusionsare a result of an intermingling of Arctic and North-Atlanticwaters and generated in the basins interior and locally viainternal wave steepening upon the sloping bottom. Freelypropagating semidiurnal lunar internal tides cannot exist withoutbackground vorticity at these high latitudes. Strongly nonlinearturbulent bores are not observed at the tidal periodicity,but wave fronts occur at the sub-inertial frequency of dominantbaroclinic instability. The fronts are in part associatedwith near-buoyancy frequency internal waves (breaking).The details of the moored T observations and their spectralcontent demonstrate the non-smooth, relatively turbulentdevelopment including convective overturning and shearinducedinstabilities when intrusions disperse in presumablysalinity-compensated isopycnal layers.
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