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clean, aerosol-free conditions
In a pure Rayleigh atmosphere in absence of aerosol the location of the
sun is not visible at all (in reality, the direct sun is of course
visible but the diffuse radiance carries no indication of the location
of the sun)
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volcanic background conditions; boundary layer horizontal visibility 50km
The location of the sun is clearly visible due to the forward scattering by aerosols
which causes an aureole around the sun. Please note that in the volcanic background
case most scattering is due to the boundary layer aerosol which was assumed constant
for all four cases.
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moderate volcanic conditions; boundary layer horizontal visibility 50km
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high volcanic conditions; boundary layer horizontal visibility 50km
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extreme volcanic conditions; boundary layer horizontal visibility 50km
With increasing stratospheric aerosol load the aureole becomes stronger and
the sky close to the sun becomes more and more red; nevertheless the color is still
dominated by blue because the larger fraction of the sky is still blue. For a completely
red sky we probably need broken clouds.
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This 360° panoramic view is probably not what a painter would paint.
Please click