If you break it down, sunlight is the same all over the world. What really matters is what’s in the air.
Dust particles and moisture will diffuse the sun’s rays, giving different areas different qualities of light. Light rays from the sun are invisible. They only become visible when they hit something. The best example is the moon at night. The light leaves the sun and we see the moon glowing in a dark sky. The light between the sun and the moon is invisible. It’s not until it hits the moon that the light becomes visible. So the quality of light is the result of those light rays striking something. Since our atmosphere in this part of the country is the way it is, the sun’s rays have less junk in the air to strike than other places, giving us our particular quality of light.
The latitude has something to do with it, too. It’s the angle. Most artists like to paint in the morning or late afternoon because when the sun gets lower, those rays have to penetrate more atmosphere, therefore, more of the cooler rays are scattered leaving more warmer rays, and we get that warm glow which everyone really likes. Also, the sun moves farther south [along the horizon] in the wintertime and it stays pretty low in the sky, which makes it ideal to paint all day long [at that time of the year].
In the mountains the air is pretty clear, which gives us sharper focus for objects that are distant. Usually the farther away things are, the softer they become as all the things in the atmosphere become like veils. Because our air is typically so clear, things that are 10, 15 or 20 miles away can appear as clear and sharp and dark as something nearby. This is a totally different problem from the coasts where moisture in the air changes the way things appear.
In Pueblo, we’ve also got the river running through town. And there are mornings where there is fog in town but it’s clear everywhere else. Certainly the placement of the river affects the quality of light in the Pueblo area.