Measuring internal waves and turbulance with aquadop

I am studying the creation and dispursion of salinity stratification in a slow flowing river. High salinity layers can form on the bottom of the river (see attachment) and because of the strong density gradient are resistant to mixing. Can I use an aquadop profiler to measure the turbulance at the interface between the two layers? I figure the method would be to measure the orbital velocities similar to the PUV waves method. However since the stratification acts as a barrier to turbulant edies propigating downwards, the velocities need to be measured at/above the interface. Can this be acheived with normal profiling at 1Hz sampling frequency? Would it be better for the aquadop to be deployed at the bottom looking up, or the top looking down or somwhere in the middle?

I forgot to mention that I can use the aquadop profiler with the high resolution pulse coherence firmware.

Hi, thank you for posting. I must admit I don't have a lot of experience in measuring turbulence in situations like this and the first thought that comes to mind is that there will be lots internal (gravity) waves propagating back and forth. These waves somehow need to be separated from the turbulence and this is hard because of the issue of finding the "true vertical coordinate system". My second thought is that the interface may act as a scattering interface because particles of density in between that of salt and fresh water will sink to down to the interface but no further. This is a complicating issue for HR profilers, which rely on acoustic scattering profiles that are close to homogenous.

In sum, I think this is a fairly hard problem and that you may need to test different configurations before you find the best way to conduct the experiment.

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Best regards, Atle Lohrmann