What is the primary driver of the water cycle?

The primary driver of the water cycle is the sun. It provides the necessary energy for the processes involved in the cycle, such as evaporation. When the sun's rays warm bodies of water, they cause water to evaporate and change from liquid to vapor. This vapor then rises into the atmosphere, cools, and condenses into clouds. Eventually, this condensed water returns to the surface as precipitation (rain, snow, etc.), which is an essential part of the water cycle.

The sun's energy also influences temperature and weather patterns, which further affect how water moves through the cycle. Without the sun's heat, the processes of evaporation and condensation would not occur efficiently, and the water cycle would be significantly disrupted. Thus, the sun is the fundamental force that drives the entire cycle of water on Earth.