Science topics

Even though our planet is called "Earth," more than two-thirds of the surface is covered by water. There is water everywhere, in rivers, in lakes, in oceans, and in clouds. Most of this water is contained in the oceans; the Atlantic, the Pacific, the Indian, and the Arctic. The Arctic Ocean is unique in that it is so cold that the surface water freezes, forming sea ice.

All three phases of water are present on Earth. There is water vapor (gas) in the atmosphere; liquid water in lakes, rivers, oceans, and rain; and solid water in snow, ice, and sea ice.