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Does any of that water, though, ever make it onto the Earth's surface? I'm guessing not, or only miniscule amounts over geologic time through volcanism. For al

Does any of that water, though, ever make it onto the Earth's surface? I'm guessing not, or only miniscule amounts over geologic time through volcanism. For all intents and purposes, I think only counting "surface" water is more useful and intuitive. It's essentially any water that can participate in the hydrologic cycle on Earth, and that water locked beneath the crust doesn't really "matter" for what I think the intended purpose of this graphic is.

dredmorbius 2y ago
The fundamental problem with complex phenomena is in defining the domain(s) of interest. If we want to talk about the total amount of H2O around, on, or in the Earth then inclusion makes sense. If we want to talk about water interacting with the surface environment (atmospheric, sea, ice cap, fresh, and subsurface aquifers and tectonic water), then splitting those into distinct categories probably also makes sense. In which case we can also show the subsurface water. How much mantle water does make it to the surface over time is a good question. I've no idea though I'd suspect that some does through geothermal and tectonic activity. The more interesting question might be how we'd determine this (all but certainly through isotopic composition), and if a net flux could be determined. Over geological time, additional reservoirs of water are significant simply because surface water boils off into space over time, with estimates I've seen of up to 25% of Earth's original allotment having done so over 4.5 billion years or so. As the Sun eventually grows warmer, this rate will increase. At the same time, tectonic activity will slow. Note that there's a fair bit of water transport through the lower crust / upper mantle as oceanic plates subduct under continental plates, with the water absorbed into the oceanic plates playing a major role in volcanism at those plate boundaries, e.g., along the "Rim of Fire" surrounding the Pacific basin.
- Symmetry 2y ago
  Earth is lucky to have a strong magnetic field and ozone layer limiting the loss of hydrogen to the solar wind. Mars, for example, has lost much more of its allotment.
card_zero 2y ago
We don't have access to any part of the planet below a depth of 2.5 miles, so the image should compare the volume of accessible water to the volume of accessible Earth, except then it would fail in its dishonest mission to make people say "gosh that sphere looks relatively small compared to the other sphere, I must restrict myself to ten-second showers." Even if it was accessible water to accessible non-water I don't really see how the metric is relevant in any decision making. Is it warning against a half-baked plan to mix water with every available cubic meter of soil or rock? Because there wouldn't be enough water to do that crazy thing? Thanks, I'll bear that in mind.
- sverhagen 2y ago
  >We don't have access to any part of the planet below a depth of 2.5 miles Given how many miles I can travel over land or through the air, 2.5 miles _into_ the earth is amazingly shallow in similar ways to how the article already anticipated my amazement of how small the spheres of water were.
- outop 2y ago
  You seem really upset about what to me looks like a quite neutrally presented fact. There are lots of interesting aspects to this picture which don't have anything to do with criticizing you or the length of your morning shower.
- dcow 2y ago
  It’s just an interesting infographic that is factually correct. You can disagree that the chosen facts are relatively the best ones, but, not everything has to have an agenda. Calling facts dishonest because they make you uncomfortable is what I consider yucky.
- lenocinor 2y ago
  I think a neat follow-up image would be a sphere containing the top 2.5 miles of Earth’s crust for comparison to the water.
berkes 2y ago
The article has a strong focus on "available to humans" and "that humans depend on". Many of the water beneath the crust is exactly that, pumping it up is an important source of drinking water. (In my country, the Netherlands, it's the primary, almost only, source of drinking water)
- globular-toast 2y ago
  The Netherlands doesn't pump water from beneath the crust! Groundwater is included in the larger freshwater sphere. Water in the mantle would be an additional sphere (not sure if it's freshwater or saltwater).
  - berkes 2y ago
    TIL. I did not get that that from the article. Thanks for correcting me. I simply presumed that water that's pumped from layers 100m or lower below the surface, water that's sometimes 10.000 years "old", wasn't surface water. But it makes sense to lump it in there too.
    - globular-toast 2y ago
      The crust is about 40km thick. The deepest anyone has ever dug is ~12km[0]. It is quite weird to think we live on this crust which has a gigantic mass inside that we can't get to. [0] https://en.wikipedia.org/wiki/Kola_Superdeep_Borehole https://en.wikipedia.org/wiki/Kola_Superdeep_Borehole
      - dotancohen 2y ago
        If you think that's weird, you'll love this. Go look at another human. There's a skeleton in there!
- autoexec 2y ago
  PFAS have reportedly contaminated water everywhere on Earth including the water in springs, confined aquifers, and even the rain that falls. Is the water pumped from beneath the crust in the Netherlands poisoned too or have you guys got the last of the good stuff?

dredmorbius 2y ago

The fundamental problem with complex phenomena is in defining the domain(s) of interest. If we want to talk about the total amount of H2O around, on, or in the Earth then inclusion makes sense. If we want to talk about water interacting with the surface environment (atmospheric, sea, ice cap, fresh, and subsurface aquifers and tectonic water), then splitting those into distinct categories probably also makes sense. In which case we can also show the subsurface water. How much mantle water does make it to the surface over time is a good question. I've no idea though I'd suspect that some does through geothermal and tectonic activity. The more interesting question might be how we'd determine this (all but certainly through isotopic composition), and if a net flux could be determined. Over geological time, additional reservoirs of water are significant simply because surface water boils off into space over time, with estimates I've seen of up to 25% of Earth's original allotment having done so over 4.5 billion years or so. As the Sun eventually grows warmer, this rate will increase. At the same time, tectonic activity will slow. Note that there's a fair bit of water transport through the lower crust / upper mantle as oceanic plates subduct under continental plates, with the water absorbed into the oceanic plates playing a major role in volcanism at those plate boundaries, e.g., along the "Rim of Fire" surrounding the Pacific basin.

Symmetry 2y ago
Earth is lucky to have a strong magnetic field and ozone layer limiting the loss of hydrogen to the solar wind. Mars, for example, has lost much more of its allotment.

card_zero 2y ago

We don't have access to any part of the planet below a depth of 2.5 miles, so the image should compare the volume of accessible water to the volume of accessible Earth, except then it would fail in its dishonest mission to make people say "gosh that sphere looks relatively small compared to the other sphere, I must restrict myself to ten-second showers." Even if it was accessible water to accessible non-water I don't really see how the metric is relevant in any decision making. Is it warning against a half-baked plan to mix water with every available cubic meter of soil or rock? Because there wouldn't be enough water to do that crazy thing? Thanks, I'll bear that in mind.

sverhagen 2y ago
>We don't have access to any part of the planet below a depth of 2.5 miles Given how many miles I can travel over land or through the air, 2.5 miles _into_ the earth is amazingly shallow in similar ways to how the article already anticipated my amazement of how small the spheres of water were.
outop 2y ago
You seem really upset about what to me looks like a quite neutrally presented fact. There are lots of interesting aspects to this picture which don't have anything to do with criticizing you or the length of your morning shower.
dcow 2y ago
It’s just an interesting infographic that is factually correct. You can disagree that the chosen facts are relatively the best ones, but, not everything has to have an agenda. Calling facts dishonest because they make you uncomfortable is what I consider yucky.
lenocinor 2y ago
I think a neat follow-up image would be a sphere containing the top 2.5 miles of Earth’s crust for comparison to the water.

berkes 2y ago

The article has a strong focus on "available to humans" and "that humans depend on". Many of the water beneath the crust is exactly that, pumping it up is an important source of drinking water. (In my country, the Netherlands, it's the primary, almost only, source of drinking water)

globular-toast 2y ago
The Netherlands doesn't pump water from beneath the crust! Groundwater is included in the larger freshwater sphere. Water in the mantle would be an additional sphere (not sure if it's freshwater or saltwater).
- berkes 2y ago
  TIL. I did not get that that from the article. Thanks for correcting me. I simply presumed that water that's pumped from layers 100m or lower below the surface, water that's sometimes 10.000 years "old", wasn't surface water. But it makes sense to lump it in there too.
  - globular-toast 2y ago
    The crust is about 40km thick. The deepest anyone has ever dug is ~12km[0]. It is quite weird to think we live on this crust which has a gigantic mass inside that we can't get to. [0] https://en.wikipedia.org/wiki/Kola_Superdeep_Borehole https://en.wikipedia.org/wiki/Kola_Superdeep_Borehole
    - dotancohen 2y ago
      If you think that's weird, you'll love this. Go look at another human. There's a skeleton in there!
autoexec 2y ago
PFAS have reportedly contaminated water everywhere on Earth including the water in springs, confined aquifers, and even the rain that falls. Is the water pumped from beneath the crust in the Netherlands poisoned too or have you guys got the last of the good stuff?