Abstract: The St. Lawrence Estuary Internal Wave Experiment

 

 

Authors: D. Bourgault, M. D. Blokhina, P. S. Galbraith, A. E. Hay, D. C. Janes, D. E. Kelley, R. Mirshak, C. Richards, G. J. Sutherland

 

The St. Lawrence Estuary Internal Wave Experiment (SLEIWEX) is a Canadian university-government partnership to study the generation, propagation and dissipation of large-amplitude internal waves (IWs) in the St. Lawrence Estuary and Saguenay Fjord coastal systems. For several years, the SLEIWEX group has been focusing on processes associated with the collision of IWs against coastal boundaries, using idealized non-hydrostatic numerical simulations as well as in-situ and remote-sensing field measurements. Some of the key results include:

1) a parameterization for the reflectance of uniform slopes for normally incident IWs,

2) field observations documenting the deformation, breaking, run-up and turbulence of shoaling internal wave trains, and

3) in-situ and remote-sensing observations documenting IW refraction and reflection off coastal boundaries.

In the summer of 2008, an intensive experiment was performed to sample IWs from generation to dissipation. To measure the dissipation associated with shoaling IWs, an array of moorings with current profilers, velocimeters and T-S sensors was deployed in the internal swash zone, in addition to concurrent CTD and current profiles taken from an anchored ship. Propagation and generation were investigated with towed echo-sounders, a suite of profiling instruments, and with remote sensing. This presentation will cover both published results and new findings from SLEIWEX, with a particular focus on IW dissipation and turbulence.