A few days ago, we wrote about a remarkable graphic released by the USGS, showing all the water on Earth—freshwater, saltwater, water vapor, water in plants and animals; all of it—rolled into a sphere.
That sphere was only 860 miles in diameter, fitting comfortably between Salt Lake City and Topeka, Kansas, on a map. It was striking, especially considering that the water available for humans use in our daily lives is only a very small fraction of that; the vast majority of the Earth’s water is saltwater, and most of the freshwater is tied up in glaciers.
How big would a sphere of just the freshwater available to humans be? Reader Jay Kimball of 8020Vision, his interest piqued, went ahead and made such a graphic:
That sphere—the sphere representing the freshwater available to humans—has a diameter of just 170 miles. Head to his blog to see the math.
When you’re trudging through the pouring rain to the office, it seems like the Earth possesses an infinite amount of water, a not-insignificant amount of which is dripping down your collar. But when you see an image like this one, produced by the USGS, it hammers home the reality of the situation: the water’s all spread out in a very thin layer, like a millimeter of frosting on a cake. If you gathered all the world’s water—from oceans, lakes, groundwater, water vapor, everything—into a sphere, it would have a diameter of 860 miles. That’s the distance between Salt Lake City and Topeka, Kansas.