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This morning, in our little backyard, I heard an airplane that was flying above the clouds, which were completely and uniformly covering the blue sky, as if they formed one big homogeneous grey mass. The wind was sleeping. It was a deep, heavy, roaring sound that seemed to last forever and it wasn't precisely clear where the sound was coming from. The sound was kinda oscillating and smooth also. It felt kinda strange to hear. If we assume the deck of clouds to have a certain constant thickness, a uniform mass distribution and take into account the temperature, pressure, moistness, and whatever (or a simplified version), what effect will this have on the sound coming from the plane towards the ground?
Will there be any scattering? Will it scatter the sound everywhere, just like the atmosphere makes the Sunlight appear to come from everywhere (in blue)? Will the soundwaves pass the clouds undisturbed? Will it depend on the sound's frequency?

Anyone who has something useful to say?

See also this Quora question.

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  • $\begingroup$ I wouldn't discount the psychological aspect - we don't often locate distant sounds using our ears alone. They're usually coming from some sound source that we can see, and being able to see the source affects our perception of how the source actually sounds (see e.g. the McGurk effect). $\endgroup$
    – probably_someone
    Commented Sep 3, 2020 at 21:04
  • $\begingroup$ That might be, but I'm pretty sure it sounded very different than a plane passing by at a blue sky day. At days when the sky is blue, I can hear where the sound is coming from after which I direct my eyes and see the plane. Or not? $\endgroup$
    – Deschele Schilder
    Commented Sep 3, 2020 at 22:29
  • $\begingroup$ I would be sceptical of any scattering from the clouds: they have nearly the same density as the surroundings, and the droplets are far smaller than the sound wavelength. What could perhaps make scattering would be some form of temperature layering (you speak of uniform overcast rather than a dynamical sky). $\endgroup$
    – Anders Sandberg
    Commented Sep 4, 2020 at 8:05
  • $\begingroup$ @AndersSandberg So there is no similarity with the blue sky? $\endgroup$
    – Deschele Schilder
    Commented Sep 4, 2020 at 8:12
  • $\begingroup$ I think acoustic impedance depends upon humidity, which is clearly higher in than out of clouds but would have to check to be sure. $\endgroup$
    – honeste_vivere
    Commented Oct 1, 2020 at 17:27

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