The smaller sphere over Kentucky represents Earth's liquid fresh water in groundwater, swamp water, rivers, and lakes. This image attempts to show three dimensions, so each sphere represents "volume." The volume of the largest sphere, representing all water on, in, and above the Earth, would be about 332,500,000 cubic miles (mi 3) (1,386,000,000 cubic kilometers (km 3)), and be about 860 miles (about 1,385 kilometers) in diameter. Are you surprised that these water spheres look so small? They are only small in relation to the size of the Earth. The globe illustration shows blue spheres representing relative amounts of Earth's water in comparison to the size of the Earth. Things would get pretty stale without the water cycle! Thanks to the water cycle, our planet's water supply is constantly moving from one place to another and from one form to another. Water also exists in the air as water vapor, in rivers and lakes, in icecaps and glaciers, in the ground as soil moisture and in aquifers, and even in you and your dog.
But just how much water exists on, in, and above our planet? About 71 percent of the Earth's surface is water-covered, and the oceans hold about 96.5 percent of all Earth's water. Spheres showing:(1) All water (largest sphere over western U.S., 860 miles (1,385 kilometers) in diameter)(2) Fresh liquid water in the ground, lakes, swamps, and rivers (mid-sized sphere over Kentucky, 169.5 miles (272.8 kilometers) in diameter), and (3) Fresh-water lakes and rivers (smallest sphere over Georgia, 34.9 miles i(56.2 kilometers) n diameter).Ĭredit: Howard Perlman, USGS globe illustration by Jack Cook, Woods Hole Oceanographic Institution (©) and Adam Nieman.
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