Man, I am dying to see something authoritative posted on this. I didn't get any good answers with a few Google searches, just some similar conflicting info and debate on some physics forums.
Here is what my "gut" thinks might be the case:
- If you are floating freely in the water column, you will probably move with the wave in a circular motion that is greater at shallower depths than when deeper. At some depth that is probably calculable by someone who actually knows this stuff, that circular motion vanishes. Within that circular motion, your gauge would probably show you a variance of depth, but a variance that is less than the variance between the crest and the trough, and which diminishes if you actively move deeper.
- If you are somehow rigidly tethered to the bottom, perhaps on a mooring line, then I would think that the crest/trough variance would have a more direct effect on your depth gauge, but again in some predictable ratio that diminishes with depth.
- Even if holding firmly to a mooring line with a significant rise and fall above, I would expect the diver to still bob around, perhaps executing just the lower half of that circle motion that I described in bullet point #1, while trying not to dislocate a shoulder on the upper half of the circle. I think you would have to be held firmly in place on a completely rigid vertical line, such as a pole, in order to experience solely the effect of the wave variance, again diminishing with depth.
