During the spring of 2015, 2016 and 2017 a SentinelV ADCP wasdeployed at a site off the west coast of Ireland, with the aim ofgathering accurate wave measurements in extreme conditions. The 5beam ADCP has 1 vertical plus 4 slant beams, and we recordedvelocities and backscatter intensity along the 5 beams continuously at 2Hz. Continuous sampling enabled us to capture details of several giantevents with crest-to-trough heights in excess of 22 meters.A number of theoretical explanations have been proposed for suchextreme waves, one of which involves directional focusing. Roguewaves may not be exclusively produced by modulational instability,which requires singular direction.While we are able to perform traditional statistical approaches to derivewave directional spectra, the array of 5 direct surface tracking beamsprovides an opportunity to construct directional estimates for short timescales or even individual events.We present here the results of an investigation into the directionalproperties of groups of large amplitude waves using time-frequencydecomposition methods applied to the surface-track and subsurfacevelocities measured by the Sentinel V.
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