The picture below illustrates the size of a sphere that contains all the water on Earth, in comparison to the Earth itself. The blue sphere sitting on top of the United States has a diameter of about 1,385 kilometres, with a volume of a colossal 1,386,000,000 cubic kilometres. The ball of water includes all of the water from the oceans, seas, lakes, rivers, icebergs as well as groundwater, water in the atmosphere, even the water in living beings, humans, animals and everything in your garden.
Credit: Illustration by Jack Cook, Woods Hole Oceanographic Institution; USGS..
Data source: Igor Shiklomanov's chapter "World fresh water resources" in Peter H. Gleick (editor), 1993, Water in Crisis: A Guide to the World's Fresh Water Resources (Oxford University Press, New York).
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