This circulation is known as the hydrologic cycle. Groundwater is part of this continuous cycle as water evaporates, forms clouds, and returns to earth as precipitation. Surface water is evaporated from the earth by the energy of the Sun. The water vapor forms clouds in the sky. Depending on the temperature and weather conditions, the water vapor condenses and falls to the earth as different types of precipitation.
Some precipitation runs from high areas to low areas on the earth's surface.
This is known as surface runoff. Other precipitation seeps into the ground and is stored as groundwater. The water then can evaporate, form clouds, and return to the earth to begin the cycle over again. The major components of the hydrologic cycle are as follows. Evapotranspiration uses a larger portion of precipitation than the other processes associated with the hydrologic cycle.