as light passes near the surface of the earth, the wavelengths increasingly blue are dispersed by fine dust particles and molecules air themselves, only the longer red wavelengths remaining. in other words, the light gets dimmer and redder as they approach the shadow of the earth line. You can see this most dramatic effect while facing away from the sun to see how the light looks an iceberg, a thunderhead, or a snowy mountain.
This painting by Frederic Church, shows the progression of colors traveling in the ice column of soft yellow through pink shades to a more neutral gray. 
This painting by master landscape Frederick Waugh shows a similar sequence of color on a very large cloud. The reddish rays towards the cloud base arrived after passing through much more atmosphere than most white rays touching the top of the cloud. Moreover, as you compare the paintings Church and Waugh, note how differently each of them depicts the color of the water and the color of the distant sky.
Although reported just over garishly, here is the color banding on Mount Shasta at sunset painted by James E. Stuart in 1921. link for Shasta paintings.
post "Golden Hour" on GurneyJourney, link.
