How much water and air sustains the Earth?

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By Science Alert Staff

 

This amazing graphic reveals the incredibly delicate balance that maintains the Earth as the only known habitable planet in the universe.

Created by Félix Pharand-Deschênes, CEO of the non-profit science communication organisation, Globaïa, this graphic shows the 1.4087 billion cubic kilometres of water in the world - including oceans, ice lakes, rivers, clouds, and ground water – in relation to the 5,140 trillion tonnes of air in our atmosphere. The air has been gathered up into a perfect sphere at sea-level density. The grey Earth in the background is to scale.

And here’s an earlier visualisation, with of all the Earth’s water, to scale, ranging from largest source to smallest source:

earth-water

Image: US Geological Survey

15 COMMENTS

  1. Earth is a rocky planet in the inner Solar-System, where it was accreted from planetesimals which had had most of their water and volatiles blasted off them by the Solar Wind and solar radiation – followed by a period when the larger consolidated inner planets continued to have their volatiles blasted off by those same energetic particles. (Earth is still losing atmosphere today from those same effects.) In the outer Solar System, it is too cold, the sunlight too weak, and the gravity of the giant planets too strong, for atmospheres to be lost.
    If anything, the outer Solar-System is gaining gas from that blasted off planets in the inner orbits near the Sun.

    The scientific hypotheses are that Earth reacquired its atmosphere and oceans, from volcanism and cometary bombardments, providing the thin coverings of atmosphere and water we have to day.

    There is a simple link on the formation of the Solar-System here:-

    http://astroclock2010.wordpress.com/cosmic-timeline-17/

  2. Wow!! Talk about a wake-up call. An image is worth a thousand words and this one is clear and unequivocal. One can only hope it gets across and contributes in educating climate deniers about the imminent danger we’re all facing. If that doesn’t work then I’m afraid nothing will.

  3. I wonder how dense those two spheres are in the air and water comparison. I had a look at the link, and it does specify the density of the air sphere as being what it would be at sea level density, which is elaborated in a comment later as:

    Average sea-level pressure is 101.325 kPa (1013.25 mbar) or 29.921
    inches of mercury (inHg) or 760 millimeters (mmHg)

    They quote Wikipedia as a source. Another comment says water is relatively incompressible, but water pressure increases quite quickly after only a few miles of depth, and the ball must be several hundreds of miles in diameter at least. Presumably the density of the core of the water ball would cause the volume to shrink a bit?

  4. Some recent findings published in June indicate that there may be significant volumes of water deep in the Earth’s mantle, albeit locked within minerals at that depth/temperature/pressure, which may even exceed the volume of water in the oceans:

    If just one percent of the weight of mantle rock located in the transition zone is H2O, that would be equivalent to nearly three times the amount of water in our oceans, the researchers said.

    This water is not in a form familiar to us — it is not liquid, ice or vapor. This fourth form is water trapped inside the molecular structure of the minerals in the mantle rock. The weight of 250 miles of solid rock creates such high pressure, along with temperatures above 2,000 degrees Fahrenheit, that a water molecule splits to form a hydroxyl radical (OH), which can be bound into a mineral’s crystal structure

    These new findings (based on lab simulation and analysis of how seismic shockwaves propagate through the mantle) are consistent with another recent finding of a mineral called ringwoodite (that is stable down at deep mantle temperatures/pressures and can lock water into its structure) within a diamond sourced from the deep mantle. The joy of science – every day’s a school day and all that.

    The only downside I can see to these new findings are that biblical literalists can proclaim “so that’s where all of Noah’s flood water went!” Oh dear, just checked, and its already happening

  5. Steve_M Jul 11, 2014 at 1:06 pm

    Some recent findings published in June indicate that there may be significant volumes of water deep in the Earth’s mantle, albeit locked within minerals at that depth/temperature/pressure, which may even exceed the volume of water in the oceans:

    Wet sea-bed sediments have been sliding down into subduction zones for “quite a long time” – although some water comes back up in magma and explosive volcanism.
    http://en.wikipedia.org/wiki/Subduction

    • Hello Alan,
      If you read the links I provided you’ll realise that the implications are that there’s a lot more water at significantly deeper mantle depths than previously demonstrated by the available data. This is above and beyond what is already known about water associated with decending slabs and crustal subduction. Although its often been surmised that there could be a lot of water deeper down in the mantle, it has now been demonstrated that water is present in appreciable volumes at depths down to the mantle transition zone, and these are significant new developments.

      • Although its often been surmised that there could be a lot of water deeper down in the mantle, it has now been demonstrated that water is present in appreciable volumes at depths down to the mantle transition zone, and these are significant new developments.

        Your earlier post quoted Ringwoodite as having a water content of water – 1.5 per cent of its weight, and linked a diagram of an upper and lower mantle with a transition zone.

        However, my linked Wiki article, mentions steep-angle subduction of plates which have “lost buoyancy, and shows a diagram of convection currents in the mantle going down as far as the Outer Core. http://en.wikipedia.org/wiki/Subduction#mediaviewer/File:Oceanic_spreading.svg – Is this incorrect?

        • Hi Alan,
          I think the Wikipedia diagram you have linked to is perhaps a little simplistic and should be used for a general idea only. The truth of the matter is that there is still a significant degree of uncertainty associated with mantle convection. The subducted oceanic crust is associated with earthquakes to a certain depth – enabling the progress of the descending plate to be directly ascertained/imaged. But below that there is more often than not no clear evidence as to how deep they go. There are tantalising glimpses of deep mantle structure which may indicate that some slab segments may each the bottom of the mantle, but there is also evidence (from clear compositional differences between shallow mantle vs deeper mantle derived magmas) to suggest that circulation/mixing between the upper and lower mantle is limited. So – still very much an area of active study and learning (although the scales are tipping towards whole mantle convection).

          As you said in your initial comment – a lot of the water associated with the descending slab is lost at relatively shallow depths, acting as a ‘voliate’ and causing partial melting – the source of the magma for oceanic (an continental) arc volcanism which recycles the water back to the hydrosphere. Any remaining water has been usually assumed to have been used up in metamorphic mineralogical changes before it reaches the mantle transition zone, largely ruling out the transfer of water to the deeper mantle.

          These new studies/findings that I linked to in my earlier post suggest that, in fact, water is still actively involved in mineralogical changes and melting at the mantle transition zone and that there is likely to be significantly more of it down there than previously thought. This also raises the prospect of longer term/larger scale water circulation involving the deeper mantle than was previously assumed.

          • Tried a couple of edits and the formatting of the links went all wrong! Hopefully it still reads ok. This is the second time this has happened to me – I obviously need to get the hang of this new commenting system and the 10 minute edit rule!!
            [EDIT} – its now sorted itself out again and all looks how it should… strange

  6. At 11 miles up, a little more than the horizontal distance I drive to work, 80% of the Earths atmosphere would be beneath me.

    It has long intrigued me the way that we differently interpret vertical and horizontal distances.

    If we are told, for example, that diver goes 300 ft down into the ocean, we think “Wow, that’s a long way down,” when the truth is that it is the distance across a parking lot, and is not considered far at all.

    I see this as an evolutionary adaption from when we came down from the trees, and our ability to estimate a vertical jump became less important than our ability to compute an horizontal distance, running maybe to a place a lion could not reach.

  7. I think an additional infographic that is sort of a 3D Venn diagram would be cool. It would show the sphere of air and the sphere of water and the overlap of the amount of water that is actually in air. Anyone ever see anything like what I’ve described?

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