[Image: Illustration by Jack Cook, Woods Hole Oceanographic Institution; courtesy of the USGS].
In Charles Fishman’s compelling exploration of water on Earth, The Big Thirst, there is a shocking statement that, despite the apparent inexhaustibility of the oceans, “the total water on the surface of Earth (the oceans, the ice caps, the atmospheric water) makes up 0.025 percent of the mass of the planet—25/10,000ths of the stuff of Earth. If the Earth were the size of a Honda Odyssey minivan,” he clarifies, “the amount of water on the planet would be in a single, half-liter bottle of Poland Spring in one of the van’s thirteen cup holders.”
This is rather remarkably communicated by an illustration from the USGS, reproduced above, showing “the size of a sphere that would contain all of Earth’s water in comparison to the size of the Earth.” That’s not a lot of water.
Only vaguely related, meanwhile, there is an additional description in Fishman’s book worth repeating here.
[Image: The Orion nebula, photographed by Hubble].
In something called the Orion Molecular Cloud, truly vast amounts of water are being produced. How much? Incredibly, Fishman explains, “the cloud is making sixty Earth waters every twenty-four hours”—or, in simpler terms, “there is enough water being formed sufficient to fill all of Earth’s oceans every twenty-four minutes.” This is occurring, however, in an area “420 times the size of our solar system.”
Anyway, Fishman’s book is pretty fascinating, in particular his chapter, called “Dolphins in the Desert,” on the water reuse and filtration infrastructure installed over the past 10-15 years in Las Vegas.
(Via @USGS).
Let's not forget that each molecule of water that evaporates — from a lake, from the ocean, from your skin — spends about 9 days floating in the atmosphere before returning to the Earth as precipitation.
Geoff, thanks for finding "The Big Thirst," enjoyed this post.
Anyone interested in the Las Vegas story can get a little taste from an excerpt from the book posted here:
http://www.marketplace.org/topics/life/big-book/excerpt-big-thirst
Charles Fishman
The Big Thirst
http://www.thebigthirst.com
cnfish@mindspring.com
That is incredible. You always hear about the fact that water covers 70% of the earth's surface. I would guess that the volume of water would be much greater.
But that is a tremendously big sphere of water! If you made a similar sphere of all the plant and animal life on Earth (including people) it would be be just a few miles in diameter — far smaller compared to the water sphere than the water sphere is compared to the Earth!
Source (wikipedia)
Yeah, spooky, but … does it mean anything? Sure, the volume of water compared to the volume of the planet is small, but so what? If you discarded everything below the surface of the planet you'd get a much more balanced image – and even that wouldn't mean anything. Maybe a graphic showing the mass of all the inhabitants of earth v. all the water on earth – that might mean something. But I doubt it.
If you discarded everything below the surface of the planet you'd get a much more balanced image—a balanced image of what? Showing the entire planet is the whole point of this comparison.
Charles, nice to see you here; I enjoyed your book.
Contrary to many modern pessimists, the water of the Earth should *not* be considered a finite resource, for all intents and purposes. The problem of purifying/desalinating/distilling water is a trivially soluble one, and the water used by human beings isn't exactly destroyed in the process.
Chin up, world!