Mode 1 Mode 2 Interactions
Internal Solitary Waves are able to travel large distances without significant change of form or magnitude, and do not interact when they come together. However, in certain conditions, they can undergo breaking - such as when they propagate over a slope, which is known as shoaling. The processes that waves undergo under these scenarios are globally and locally important in the distribution of heat, nutrients and water masses.
Depending on the steepness of the slope, and the “wave steepness” (it’s amplitude / wavelength) waves will undergo one of four different breaking processes. But we found that the type of stratification also impacted this, preventing certain breaking types from forming.
Wave Surging
This process happens for waves with low wave steepness, you can see this process happening in the lab with a small pulse of fluid surging upslope ahead of the wave:
Wave Collapsing
This process happens for waves with medium wave steepness over medium slopes. Here, a feature known as a separation bubble forms at the bed as the wave passes, and then an associated vortex causes the pycnocline to be pulled back on itself - hence the wave collapses:
This work consisted of both laboratory experiments, and the SPINS numerical model (Subrich et al., 2013) to extend our experimental output further, and to gain a full suite of simultaneous measurements not available in the laboratory.
anything on mode 2 here?
This work was published in Journal of Fluid Mechanics.