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I have heard artists talk about the unique quality of light near the sea, and now I live near the coast I want to know if there's any truth in it. Does being near the ocean affect light inland?

I'm in the UK, where it's not usually clear blue skies; it's cloudy or partially cloudy (clouds may have an effect?).

I've lived in a flattish region in the centre of the UK, and at the coast. I think it's brighter here, but I can't figure out if it's a real difference. And Google is silent.

I've come up with possible explanations:

  • It's purely psychological
  • It's a side-effect of the big horizons making places feel lighter because more sky is visible
  • Sunlight reflects off the sea, and the clouds scatter it back onto the land

Is this real? If so, what's the mechanism and how far inland does the light penetrate?

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At the coast the horizon facing the ocean is unobstructed, so a larger part of the sky is visible than inland, where trees, buildings, etc., block the view of the horizon. Also, the horizon sky is brighter than the overhead sky. At or near the horizon the sky appears lighter blue than at the zenith, or even whitish. Looking vertically at the zenith is looking through one air mass; looking horizontally at the horizon is looking through 40 air masses. Although the atmosphere scatters short wavelengths at the violet end of the spectrum most effectively, 40 air masses scatters enough of even the longer red wavelengths that the horizon sky appears very light blue or even whitish. 40 air masses is enough to scatter all of the light. Greater scattering of light causes the near-horizon sky to be brighter. (Even the zenith sky appears blue rather than violet because the Sun emits more blue light than violet and the eye is more sensitive to blue light than violet.)

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  • $\begingroup$ So how about locations in, for example, the US Plain States, where the horizon is generally almost equally unobstructed... are you suggesting they will be comparable to this coastal environment? $\endgroup$ – JeopardyTempest Aug 9 '17 at 14:57
  • $\begingroup$ There could be other factors as well. One possible other factor: Near the ocean salt particles predominate; in the Plains states soil particles predominate. The type of suspended particulate matter could also be a factor. Consider Mars, whose typically butterscotch-colored skies are due to suspended dust. If the dust were to settle, the Martian sky would be a very deep dark blue, like than on Earth in the stratosphere. $\endgroup$ – Jack Denur Aug 10 '17 at 3:09
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Sorry to be un-arty but you should be able to measure scattered light intensity at the coast versus inland. My guess is that it is brighter at the coast which also probably also means it gets lighter in the morning and light lasts longer into the evening. Land in the place I live is covered in green and is quite absorbent of light, i.e. dark. It's pretty, but the sea is usually lighter than er.. a forest or farmland. In the desert this may well be different. So my guess is that the light is special at the seaside or more special on a peninsula because there is more of it - more light and more light time at dawn and dusk. How prosaic. The light should still be measured. An explanation is good only if it fits the facts.

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