Rainwater also soaks into the ground. This is called groundwater. Groundwater flows through springs or underground streams. Groundwater also feeds into a pond, lake, or ocean, and undergoes evaporation. During dry periods, it may move upward into roots and through the soils where it will again return into the atmosphere by evaporation.
Warm air carries the water vapor upward into the atmosphere.
As the warm air arises, it loses heat, and this process causes water droplets to form. Heavy accumulations of these cool water droplets form clouds. The darker the cloud, the more concentrated the water droplets. Eventually, when enough water droplets accumulate, they form rain, which is pulled to the earth by gravity. Animals and plants are both involved in the water cycle.