On the Groupiness and Intermittency of Oceanic Whitecaps
Journal article, Peer reviewed
Published version
Åpne
Permanent lenke
https://hdl.handle.net/11250/2998099Utgivelsesdato
2022Metadata
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- Geophysical Institute [1228]
- Registrations from Cristin [10412]
Originalversjon
Journal of Geophysical Research (JGR): Oceans. 2022, 127 (1), e2021JC017938. 10.1029/2021JC017938Sammendrag
The enhancement of wave breaking activity during wave group passage is investigated using coherent field observations of the instantaneous sea surface elevation and whitecap coverage from platform-based stereo video measurements in the central North Sea. Passing wave groups are shown to be associated with a two to threefold enhancement in the probability distribution of total whitecap coverage W whereas the enhancement of active whitecap coverage WA is approximately fivefold. Breaking time scales and intermittency characteristics are also investigated with the inclusion of a secondary data set of W and WA observations collected during a research cruise in the North Pacific. The time scale analysis suggests a universal periodicity in wave breaking activity within a representative sea-surface area encompassing approximately one dominant wave crest. The breaking periodicity is shown to be closely linked to the peak period of the dominant wave components, suggesting that long-wave modulation of wave breaking is a predominant mechanism controlling the intermittency of wave breaking across scales.