Ideal water waves are surface mechanical waves which are ruled by wind (disturbing force) and gravity (restoring force):
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The motion of water particles is expected to produce a slow-oscillatory pressure wave close to the surface. As the associated water wave propagates far slower than sound waves (~m/s versus ~km/s), I believe that the pressure produced by the water wave can be approximated as an RMS pressure offset at the temporal scale of a sound wave period or as a slow RMS pressure oscillation as compared to the duration of an animal call.
What is the order of magnitude of this water wave pressure offset as compared to the RMS pressure due to underwater animal communication? This question depends of several parameters, so feel free to fix some of them, e.g. water depth where water wave pressure is considered (e.g. 2m), a typical sound level of a given animal.
I'm just curious to know whether this slow pressure oscillation is present in practice in your underwater pressure recordings close to the surface, or if it is just negligible (I have no experience in underwater recordings), and then to better understand the relationship between acoustic waves and others types of mechanical waves as discussed in this other question.
- I don't want to discuss any sounds that could be produced indirectly by the water wave (as in this question). Here, let's assume a pure water wave propagating slowly (~m/s) which does not produce acoustic effects (i.e. not producing any pressure wave propagating at ~km/s).
- The type of wave I want to consider is a wind wave according to this Wikipedia entry about types of water waves based on spectrum, and maybe more precisely an ocean swells according to this way of categorizing wind waves even if water particles move a little differently than with ideal water waves (i.e. additional drift - see this animation versus that one).