In the renaissance, fine art painters invented an image-making technique called "atmospheric perspective" (also sometimes called "aerial perspective"). It refers to the way in which items portrayed as further in the background are done so with softer colors. This creates the illusion of depth by showing how earth's atmosphere as a softening effect on color, light, and shadow.
Since the invention of photography, many have captured this sort of effect as it happens in nature with great success. So, behold below a collection of misty pictures, each revealing layer after layer of earth softening in the foggy distance.