The Water Cycle Oceans hold most of the water on the planet. The water there is salt water. When the sun heats the ocean water, evaporation begins the water cycle. The water vapor created by evaporation contains no salt and the salt remains in the ocean. The water vapor moves over the land areas of the planet as clouds.
Clouds provide rain, snow, and other precipitation to the land.
While most of the precipitation falls in the ocean, the rest provides fresh water to the land. Some additional water vapor is provided from evaporation on the land from lakes and rivers and from transpiration from plants. The precipitation that falls on the land provides needed water to plants and then either goes to ground water aquifers or into lakes and rivers. Once fresh water finds its way into rivers, it will eventually flow back into the oceans where the water cycle begins again. Rivers Wildlife and fish depend on rivers as do a number of cities for drinking water and businesses for use in manufacturing processes.