Observations of small-scale secondary instabilities during the shoaling of internal bores on a deep-ocean slope

• Published in: Journal of Physical Oceanography
• Main Authors: Cyr, F., van Haren, H.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2016
• Subjects: Rockall Bank; North East Atlantic
• Online Access: https://www.vliz.be/imisdocs/publications/35/299735.pdf

The Rockall Bank area, located in the north-east Atlantic Ocean, is a region dominated by topographically-trapped diurnal tides. These tides generate up-and down-slope displacements that can be locally described as swashing motions on the bank. Using high spatial and time resolution of moored temperature sensors, the transition towards the upslope flow (cooling phase) is described as a rapid upslope-propagating bore, likely generated by breaking trapped internal waves. Buoyant anomalies are found during the bore propagation, likely resulting from small-scale instabilities. The imbalance between the rate of disappearance of available potential energy and the dissipation rate of turbulent kinetic energy suggests that these instabilities are growing (i.e., young), suggesting high mixing potential.