Internal waves and internal solitons shoaling 
and breaking along a continental slope.

Thiem, Ø., Avlesen, H., Alendal, G. and Berntsen, J.

Technical Report No. 14, Bergen Center for Computational Science, 
Bergen, Norway, 2005.

Measurements in the Ormen Lange area, at the continental shelf slope outside mid Norway, have revealed 
several occurrences of high speeds near the seabed often connected to temperature or salinity variations.

In this report it is investigated if internal waves or internal solitons can lead to the measured events.
Since these kind of waves exists in all oceans and can propagate for hundreds of kilometers without
significantly loosing the amplitude the generation area does not need to be located close to where the
shoaling occurs.

The numerical results show that the shoaling of internal waves or solitons along a shelf slope can lead
to breaking and generation of boluses that can propagate up the slope. During these events the maximum
horizontal velocity of the wave can be intensified up to almost 10 times. The results show that the
maximum velocity during a breaking and run up event depends on the amplitude of the wave and the steepness
of the slope. The combination of a gentle slope and a internal wave with big amplitude leads to the highest
velocities. These velocities is shown that can exceed 1.0 m/s when the internal wave or the internal soliton
have an amplitude of 100 m and the slope is 0.05.

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