What is the primary driver of the water cycle?

The primary driver of the water cycle is solar energy. This is because the sun provides the energy required to evaporate water from oceans, lakes, and rivers, transforming it from liquid to vapor. This process of evaporation is essential in initiating the water cycle. Once water vapor rises into the atmosphere, it cools and condenses into clouds, eventually leading to precipitation in the form of rain or snow, which returns water to the Earth's surface.

Solar energy is pivotal in driving these processes, as it not only fuels evaporation but also influences atmospheric temperatures and circulation patterns, which are crucial for the movement of water vapor within the atmosphere. While other forms of energy, like wind, geothermal, and tidal energy, play important roles in various Earth processes, they do not have the same fundamental impact on the water cycle as solar energy does.