Water is essential for life as we know it. It is present throughout the Solar System, and was part of the Earth from its formation. The source of the water was the same as the source of the Earth's rock: the cloud of particles which condensed in the origin of the solar system.
The cycle[change | change source]
- First, water on the surface of the Earth evaporates.
- Then, water collects as water vapor in the sky. This makes clouds.
- Next, the water in the clouds gets cold. This makes it become liquid again. This process is called condensation.
- Then, the water falls from the sky as rain, snow, sleet or hail. This is called precipitation.
- The water sinks into the surface and also collects into lakes, oceans, or aquifers. It evaporates again and continues the cycle.
References[change | change source]
- Van Andel, Tjeerd H. 1994. New views on an old planet: a history of global change Chapter 14. 2nd ed, Cambridge. ISBN 0-521-44755-0