And THIS Tiny Sphere is All the World's Water *That We Can Use*

By Veronique Greenwood | May 18, 2012 2:46 pm

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.

  • jaykimball

    Thanks Veronique. As the tiny sphere shows, fresh water is very precious thing. As the population has grown to over 7 billion people, well on its way to 10 billion by 2100, it takes a lot of water to grow the food that feeds us all. For those readers interested in learning more about water scarcity in the US, see:

    It is the second most read article at 8020 Vision. Interestingly, the number one article is on fracking, which poses increasing risk to clean water in communities around the world, especially in the US Northeast.

    Jay Kimball
    8020 Vision

  • sam

    Err, this is a deeply misleading way to think of things. If you take the entire human race and roll it up into a ball, how big is it? For 7 billion people weighing 150lbs at a density of 1g/cm^3 I get a sphere with diameter of about 0.6 miles. That’s a pretty tiny ball of human for so much water…

    (By the way, I do think maintaining our fresh water supply is an important problem, I’m just pointing out that this is not an instructive way to think about it).

  • jaykimball


    Regarding your analogy about how much space humans take up – Yes, humans take up a remarkably small amount of physical space. I have heard it said that all people, standing shoulder to shoulder, would take up about the state of Texas. Doesn’t seem like much. But what is important, in my view, is what we 7 billion people do on our little planet. Turns out that to feed, cloth, entertain, drive, etc. consumes vast amount of resources and leaves a path of pollution that goes way beyond the minimal space we occupy.

    Focusing in on fresh water, even though the average American has inside them about 44 liters of water, we consume about 1,000 liters per day inside the home, and outside the home. So even though we confine a small space, and contain a small amount of water, human activity has resource requirements far beyond the cubic centimeters we take up on the planet.

    For more on this, see:

    That article examines, even if the population stopped growing today, what happens as the developing world “wants their MTV” and to live the American lifestyle? The second chart in that article, showing per capita energy use, is a great example of how consumption rises with affluence.

    Jay Kimball
    8020 Vision

  • Iain

    We can use the oceans, desalinate, but we don’t have the will because there is so much other (cheaper) available water. Shock tactics may work for the uneducated or unwilling to investigate, however I don’t believe shock tactics are a good approach here.

  • SGTG

    Guess we’ll have to start looking around for asteroids that *may* have a chance of holding *usable* water. Has anyone looked into this yet? If so, give a link. That calculation about the human race rolled up int a ball was pretty cool. I never knew that the human race would only take up a size approximately the state of Texas.

  • Vorn

    That’s a lot bigger sphere than I thought it’d be…

  • MoGlee

    And THIS tiny ball is earth in the solar system, to put the ridiculousness in perspective:

    Can someone put up spheres indicating:
    1. All forest life
    2. All non-human, non-plant life
    3. All humans
    I bet they would be smaller!

  • Avattoir

    Oooo, keep going with this theme!

    How about making a same-density “mass” ball comparison of all planetary surface water with (against, versus) the planet’s oxygenated surface-to-space atmosphere? By crikey, that’d be a eyeball goggler!

    Also, taking the comment about on how much fresh water the average member of the modern fathead hominid ape species uses daily, how about taking that amount (The commenter says 1,000 litres, but if the actual number is smaller, va naturale!), multiplying it (expanding it) by 7 billion, then comparing the various blobs of Blobby Earth, Blobby Earth Water, Blobby Fresh Water, and Blobby Average Daily Fathead Use of Fresh Water.

    Then how about a blobby for the fresh water replacement rate? A blobby depicting the planet at the same density all the water blobbies?

    Plus – don’t forget the marketing: Blobby paper weights, Blobbleheads, and, of course, Blobby water marks!

    (Tho you’ll have to deal with this:

  • Aidan

    It seems incomprehensible to think this graphic is accurate, I always thought of the Earth’s surface being almost nothing but water, and deep at that but…

  • jaykimball


    Yes, it seems like with all the oceans, there is water just sitting there. But to desalinate takes massive energy. Energy is increasingly expensive. California is investing $6 billion in water storage tanks to capture rainwater runoff, because that is cheaper than desalination.

    One of the most effective things we can do is get better at conserving. Drip irrigation rather than brute force sprinkler and field flooding, for example. Smart use of waste water. For example, there are 66 golf courses in Palm Springs. On average, they each consume over a million gallons of water per day. That needs to change. They should be using gray water. Palm springs is a desert. Fresh water is precious. No need to waste it keeping a chemical-laden lawn perfectly green.

    There’s a good movie that just came out that takes a good look at water, what we should know, and how to manage the resource better. The movie is called Last Call at the Oasis. Here’s more on that:

    There is a stunning image of Lake Meade, which supplies water to Las Vegas, and electricity too. Check it out.

  • BP

    Is this simply the volume of all the known lakes and rivers or does this also include water in the atmosphere and underground?

    Also since rivers have a flow that changers but never stops over a season, does this represent a moment in time or a day, a month, a year?

    Neat graphic, but I like to see it adjusted for real values :)

  • ohgoodgrief

    Fortunately, water is recycled constantly by nature itself, so you may be drinking the same water molecule that a man in India flushed down the drain. 😉

  • Brandoch Daha


    His point about the total mass of humans on the Earth is that intuition and emotion tell us nothing useful about these things. They’re great if you’re a comment spammer trolling for money from people who are easily panicked and stampeded, but then you’re just a scam artist, and not everybody wants to be one of those.

    Numbers are meaningless without scale and context. What are you comparing it to? When somebody tries to panic me by yelling giant scary numbers, I ask him what he’s comparing it to. If all I get is another rehearsed pitch full of non sequiturs, emotional appeals, and numbers without context, I just say “no herbal v14gara for me, thanks” and I go on about my business.

  • Johann Amadeus Metesky

    One reason why I’m glad to be living in Michigan.

  • onlyme

    And no mention is made of the fact that fresh water supply continually renews itself through such amazing processes as rain and snow. Yeah, there is need for recycling and conserving, but as with almost all “green” propaganda, alarmism rather than data is the approach taken in presentation. It is hard to scare people with the facts, especially when there is no basis for fright inherent in the facts.

  • jaykimball

    BP: That is the volume of water in lakes, rivers, and underground. Atmospheric water is minimal – about .001% of total water. Water in rivers is the total volume of all rivers at a point in time. Sometimes heavy rains swell a river, but the river flows to the sea and adjusts back to a nominal level. See the link to 8020 Vision, above, for details about the source data.

    Brandoch Daha: You said “Numbers are meaningless without scale and context. What are you comparing it to?” The comparison is to the Earth. We superimpose the water spheres over the Earth to compare the relative volumes. Looking at an ocean on the surface of the Earth, but not knowing how deep the ocean is, relative to the Earth, one can have the vague impression that there is more than meets the eye. By collecting the water into spheres, we can compare them on an equal footing.

    onlyme: Regarding your comments on rain and snow, the spheres above account for the rain and snow. For the source data, follow the links above. We generally access our fresh water through groundwater, lakes and rivers. Snow melts and moves to the rivers. Snowpack is in decline, so river flow is in decline too. Some estimates suggest that most of the snowpack in the Rockies will be gone by 2050. This will have profound impact on the Colorado river and all the agriculture and municipalities that depend on it’s flow. So you are right, conserving and recycling are really important.

    As snowpack and river flows decline, we are drawing on groundwater more. But that is not sustainable. In the US, 21 percent of irrigation is achieved by pumping groundwater at rates that exceed the water supplies ability to recharge.

    The US south is drying up. From Florida to California, fresh water is in decline. For example, by 2020, California will face a shortfall of fresh water as great as the amount that all of its cities and towns together are consuming today. As I mentioned above, California is investing $6 billion in water storage tanks to capture rainwater runoff, to supplant the water lost from snowpack and river flow declines. That’s a good thing. It takes time to adapt to the changing climate. Clean safe water is so basic to everything – drinking, agriculture, etc. – that it is good that governments around the world are paying attention to this and planning accordingly.

  • Lauren

    I’m not sure I understand the accusations of “alarmism” here. The spheres correspond to hard numbers/data. There are no dramatized claims or interpretations of date. Volume is measurable.

    Also, to sam: That water has to supply WAY more than the human race – like all of other living things on Earth. I doubt the volume of humans even comes close to the volume of total living things on the Earth.

  • Gary

    The illustration is still misleading. All of the water is represented as a sphere in comparison to the entire earth. All life, not just human life, exists on or very near the surface. If you were to take all of the land surface to a depth of say 1/2 mile and all of the ocean water you would have a sphere only slightly larger than the water sphere.

  • http://Time Tickles

    So global warming isn’t such a bad thing if it increases the water supply, huhhh?

  • rosemary


    Tell that to Texas. Tell that to the Southwest. Tell that to the farmers and ranchers.

    Which water supply is Global Warming increasing?

    Glaciers going in to the sea isn’t helping. Snow pack in the mountains melting away isn’t helping. Extreme rain, flooding farmland and towns, isn’t helping.

    How are you helping? Get busy, or get out of the way…

  • cocoajohn1

    How about making a sphere comparing the amount of USEFUL information we get like this as opposed to all the information that is simply tossed our way?

  • Jonathan Kemp

    interesting annology of human density sphere .6 mi dia., and remember that humans made of mostly water too


    Those of you talking about the rain water “cycle”, rainfall, renewable water supplies, etc are missing the fact that the water we take from Aquifers DOES NOT go back into the drinking supply at anywhere near the rate that we take it out. For one thing, emptying the aquifers cause them to sink, “SUBSIDE” so they will never again hold what they did when we started pumping. Also, evaporated water is just as likely to fall into the ocean, or other unusable areas so we lose some there. Then there is the pollution that occurs as the water we recycle tries to get back down through the ground into an aquifer. Read or watch “Blue Gold” on Netflix to get a more complete view of the problems of fresh water around the world. And if global warming causes the ice to melt there is no reason to believe that we will benefit by having it as potable water. People who worry about “Fracking”, water pollution, and water conservation are not just being alarmist. In many communities water rates are going up, up up, and there is also a timeline in which there is NO more fresh water in an area. Conserving water is upon us now. Do you have children? Where they get to live will be dependent on water. Already in some countries drinking water is owned by private companies and if you don’t pay you don’t get water. Think about that.

  • Jim M

    What % of the total fresh water is recycled as precipitation? Isn’t that the crucial datum? Doesn’t that % define sustainable water usage for the planet? After that it boils down to how you want to allocate it. Trees, crops, drinking water…car wash etc.

  • jaykimball

    Jim M:

    About .001% of water is atmospheric. On a finite planet, with a relatively closed system, it’s not so much that water gets recycled. Mostly the problem is that it gets polluted, or relocated. We want to make sure that we have clean safe potable water for drinking and farming, where we need it.

    But with 7 billion people consuming and polluting at an exponentially increasing rate, that is a challenge. There is less and less clean safe potable water each year, and much of the potential sources are drying up – e.g. snowpack, lakes, aquifers. Mostly that water is going to the sea. And though sea water is plentiful, it takes massive energy to desalinate. And it takes energy to transport the water inland. Energy prices are rising to as global demand for energy, especially from China, increases.

    Wouldn’t it be easier if we just consumed more appropriately to the conditions at hand. Take Palm Springs for example. It’s a desert, and to waste a 18 million gallons a day keeping the golf courses green is not rational. They should at least be using gray water. For more on this, see:

    Human demand for fresh water is impacting the traditional water sources. As is climate change. The aquifers and lakes are being drawn down faster than replenishment. The snowpack is melting.
    By 2025, 1.8 billion
 people will live in conditions of absolute 
water scarcity, and 65 percent of the worlds population will be water stressed.

    These are good things to be thinking about now, because it will take a lot of time and money to adapt to these enormous changes. Not in a panicked fearful way, but in a rational informed way. It’s a finite planet, and we want to make sure we understand the limits and conduct our selves accordingly.

  • Chris the Canadian

    I love living in Canada, where fresh water flows in rivers and lakes and ponds and streams and everywhere you turn. Can’t wait for the mid 21st century when the hottest commodity on the market will just happen to be the one natural resource we happen to have in huge supply, moreso than any other nation in the world.

    Want water? That’ll be 4 bucks a gallon please 😀

  • Jim M

    The 0.001% ? Does that repesent the water in the atmosphere at any given moment? The answer I’m looking for is the percent returned to earth annually as percipitation (fog dew rain snow etc)

  • jaykimball

    Jim M:

    Yes. There is a constant cycle of evaporation, atmospheric storage, condensing into precipitation, absorption by ground, run-off, river flow, etc. The .001% is average held in the atmosphere, at any given moment. You may find this interesting, regarding rainfall:

    There is some stunning video in the article.


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