2. Colors in nature have universal meaning. For example, trees and plants are green, so the color green often represents life and nature. Blue, the color of the sky, oceans, and lakes, makes us think of air, water, and peace. Colors in the red spectrum—yellow, orange, and red –are warm colors. Those colors may give us a feeling of warmth and comfort or feelings of anger. Colors in the blue spectrum—colors such as blue, green, and purple—are cool colors. They often give a feeling of calmness or sadness. These ideas about color are similar around the world