Physical science sea

Physical science

Composite images of the Earth created by NASA in 2001
Further information: Physical oceanography
Earth is the only known planet with seas of liquid water on its surface,[3](p22) although Mars possesses ice caps and similar planets in ot

her solar systems may have oceans.[11] Earth’s 1,335,000,000 cubic kilometers (320,000,000 cu mi) of sea contain about 97.2 percent of its known water[12][c] and cover more than 70 percent of its surface.[3](p7) Another 2.15% of Earth’s water is frozen, found in the sea ice covering the Arctic Ocean, the ice cap covering Antarctica and its adjacent seas, and various glaciers and sur

face deposits around the world. The remainder (about 0.65% of the whole) form underground reservoirs or various stages of the water cycle, containing the freshwater encountered and used by most terrestrial life: vapor in the air, the clouds it slowly forms, the rain falling from them, and the lakes and rivers spontaneously formed as its waters flow again and again to the sea.[12]