Artist 
Writer Atmospheric perspective
The control of hue, saturation, and value of a color in order to create the illusion of a landscape (or still life) receding into the distance.
Objects are affected by the atmosphere between it and the viewer. As the distance between an object and a viewer increases, the contrast between the object and its background decreases.
The colors of the object also become less saturated and lose the reds and yellow, leaving only a blue hue. For example, distance hills lose the green of trees and grass and become more blue purple.
See the Observation Building Block for more information.