What near visible wavelengths will propagate through the atmosphere, and more specifically clouds and haze, to provide useful high resolution (~1ft?) imagery from space?

  • $\begingroup$ What have you looked up on the web, to avoid duplication of answers. The easiest way to find out, is to google images for the appropriate graphs illustrating wavelengths which are most likely to reach the ground. $\endgroup$ – user154420 Jul 9 '17 at 19:43
  • $\begingroup$ My understanding is that the modeling approach is to take atmospheric slices. I also understand that the scattering is different dependent on the wavelength. I have heard it said, for example, that imagery of LWIR may be processed to create higher resolution images. $\endgroup$ – mongo Jul 9 '17 at 20:15

See Which frequencies of IR and UV light best penetrate the atmosphere with least interference? for transmission by wavelength.

But pretty much nothing (short of radio) will go through clouds there is too much scattering even if the wavelengths aren't absorbed by water vapour.

For imaging the absorption/scattering is the least factor to consider. In (near) visible light you are using reflected sunlight so you need to consider how your target reflects. If the target reflects all wavelengths equally then you will see nothing ! Certain wavelengths are commonly used for crop survey for example because different plants (or the same plant ripening) reflects very differently. As you go to loner wavelengths (>8-10um) the majority of the signal comes thermal emission of the background so you will see little difference between different objects at the same temperature.

  • $\begingroup$ Then the question is how much water vapor causes what level of scattering? $\endgroup$ – mongo Jul 9 '17 at 20:15
  • $\begingroup$ And your link, which referenced 8-14 microns, is getting closer to what I am looking for. $\endgroup$ – mongo Jul 9 '17 at 20:17
  • $\begingroup$ @mongo Note that, as mentioned in the answer, clouds are not transparent in the IR window. $\endgroup$ – tfb Jul 9 '17 at 23:40
  • $\begingroup$ OK, if we eliminate seemingly opaque clouds, then how much does a thin cirrus layer degrade things? With respect to thermal emissions, where can I find attenuation and scattering data? $\endgroup$ – mongo Jul 10 '17 at 0:18

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