Distribution of water on Earth
Water, on Earth, can be found in any of its physical states (frozen, liquid, and in the form of water vapor). Water is the basis on which all life on the planet is sustained, since all living beings are made up of water and need it to live. Humans, in addition to living, also need water for our activities, but it is not always available.
The hydrosphere is the discontinuous layer of water that is on the earth's surface or below it. The hydrosphere includes all surface water masses (liquid and solid), groundwater, and water vapor in the atmosphere.
Almost 3/4 of the Earth is covered by water. Although the amount of water in the hydrosphere is very large, only 2.5% is fresh. The rest, 97.5%, is found in seas and oceans, but it is salt water and cannot be used for drinking, agriculture or most human activities. And of the fresh water, much of it is in the polar ice caps and in groundwater, so there is only very little of Earth's water available to humans.
|water situation||Volume in km³||Percentage|
|Sweet water||Saltwater||fresh water||total water|
|oceans and seas||-||1,338,000,000||-||96.5|
|Polar ice caps and glaciers||24,064,000||-||68.7||1.74|
|continental glaciers and permafrost||300,000||-||0.86||0.022|
|fresh water lakes||91,000||-||0.26||0.007|
|salt water lakes||-||85,400||-||0.006|
|Humidity of floor||16,500||-||0.05||0.001|
|Total fresh/salt water||35029110km³ (2.5%)||1350955400km³ (97.5%)||100% fresh water
|Total water on Earth||1386000000 km³||-||
100% full water
Fuente (modificada): Wikipedia