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There's a common (almost clichéd) claim that you can only hear some distant sound "depending on the wind direction".

Here are some random examples.

  • The local population does not have to expect any noise emissions because the test pile is situated about 2.3 km from the coast. Depending on the wind direction, dull thuds at the most may be heard on the cliff coast. [1]
  • depending on the wind’s direction you began to smell the smoke of the wood fire or hear the sounds of Ethan’s delicately constructed music. [2]
  • Depending on the wind direction i'll probably be able to hear most of the arctic monkeys gig from my back garden... [3]
  • you can hear cows or horses and, depending on the wind direction the milk machine in the morning (5.30) and afternoon (5.30).[4]

My intuition (which I naturally don't trust) suggests that the amount of distance that the sound is advanced by a small wind in the time it takes to travel to the ear is irrelevant.

Using my first example, travelling at 343 metres per second, the sound is going to take about 6.7 seconds to reach the coast, 2.3km away. If the air is moving at, say, 3 metres per second (which is enough to cause leaves to rustle, but not enough to cause waves to break [Ref], it means the sound could, at most, be heard an additional 20 metres further (compared to still air), or 40 metres further (compared to the same wind heading away from you). Over a distance of 2300 metres, the difference in loudness caused by an additional 40 metres seems like it should be imperceptible.

Yes, the wind might be faster, but again my intuition suggests this would break-up and/or cover the sound more than it would assist the sound.

Does this expression have a basis in truth? Is it ascribing the fact that one can only sometimes notice the sound to the wrong cause?

  • Is the claim in your question basically "Is it true that the wind can make me hear better?"...? I'm asking because from your title it seems you're talking about the opposite, which is quite known (and you mention this in your second last paragraph). Or maybe it's just me... :) – Alenanno Jan 31 '12 at 11:53
  • I'm slightly confused, but I am going to say "Yes" with a caveat. I am excluding gale-force winds, which I am sure everyone agrees will drown out other sounds. "Is it true that the wind can make me hear further?" is probably a better formulation. – Oddthinking Jan 31 '12 at 12:21
  • I'm thinking it could possibly be the pressure differences that exist with wind rather than the wind itself that makes people think this. – JaseMachine Jan 31 '12 at 13:38
  • @Oddthinking Yeah but if you want to leave it like this it's ok, since it is neutral, it can be interpreted both ways. I was mostly talking about a feeling of mine, so if someone else shared it, it could improve your question title. :) – Alenanno Jan 31 '12 at 13:58
  • @Alenanno, I've no objection to the question being edited for clarity, but I haven't quite grasped your concern, so I can't do it myself. – Oddthinking Jan 31 '12 at 14:35
14

Yes, and together with temperature it is studied to gauge the effects of large noise hubs such as airports:

The presence of wind causes a two-fold effect. The first effect is refraction due to wind gradients, dw/dz, and the second is convection due to a constant wind. Wind gradients refract the rays as shown in figure 4. The rays are refracted upward when flow with a positive dw/dz is approaching the acoustic source and downward when the same flow is moving away from the acoustic source.

enter image description here

Convection results in an increased effective sound speed in the direction of the flow. This effect is usually small with respect to the refractive effect of the wind gradient, and thus, is difficult to see on the resulting ground contours. The convective effects are represented by a slight horizontal shift of the ground contour from the source center and will be discussed further in the results.

Wind gradient effects shown in figure 4 are angularly dependant. The maximum upward refraction occurs in the direction toward the oncoming flow and diminishes until there is zero refraction perpendicular to the flow. Similarly, the downstream downward refraction also diminishes as it approaches a line that is perpendicular to the flow.

source

  • Humidity plays a role too. – Benjol Dec 20 '12 at 10:06
  • @Sklivvz: concerning Fig. 1 in your source (audibility survey of Oppau, Germany): did they just interview people downwind of the explosion? There are hardly any circles (not heard/heard) upwind of the source. – jjack Sep 28 '15 at 17:47

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