Final answer:
Water vapor can become ice through a process called sublimation, where ice and snow change directly to water vapor without first melting to form liquid water due to the heat from the sun.
Step-by-step explanation:
Water vapor can become ice through a process called sublimation, where ice and snow change directly to water vapor without first melting to form liquid water. This occurs because of the heat from the sun. When water vapor comes into contact with a cold surface, such as the surface of ice, it loses heat energy and transforms directly into solid ice.