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umvi parent
> This sphere includes all of the water in the oceans, ice caps, lakes, rivers, groundwater, atmospheric water, and even the water in you, your dog, and your tomato plant.

Does it include water in the mantle? (https://www.bnl.gov/newsroom/news.php?a=111648)

or other non-liquid water for that matter like hydrates (ebsom salts, etc)

dredmorbius
Given that the quantity of water in the mantle is thought to be equivalent to that in all the oceans (large drop), I'd presume not.

The mantle-water research is fairly new, with this report from 2017:

"There’s as much water in Earth’s mantle as in all the oceans"

<https://www.newscientist.com/article/2133963-theres-as-much-...>

The USGS detail pages are based on a 1993 publication, Igor Shiklomanov's chapter "World fresh water resources" in Peter H. Gleick (editor), Water in Crisis: A Guide to the World's Fresh Water Resources (Oxford University Press, New York).

<https://www.usgs.gov/special-topics/water-science-school/sci...> and <https://www.usgs.gov/special-topics/water-science-school/sci...>

marcosdumay
Yep, it's quite misleading since the region where they looked for water at all is an incredibly thin layer on the outside of the planet, but they show it all as if it applied to all of the volume.
DiggyJohnson
There’s nothing wrong with their representation. You’re describing a different comparison.
marcosdumay
It's not bad on purpose if that what you understood.

But the comments here are full of "it's so little!" variants, where if you took the rest of the Crust and smashed as a sphere, it wouldn't be much larger than the water one.

It did evidently mislead a large number of people.

moralestapia
No, it doesn't. It includes all of the water in the oceans, ice caps, lakes, rivers, groundwater, atmospheric water, and even the water in you, your dog, and your tomato plant.
FredPret
"Groundwater" is a little ambiguous - H2O in the mantle is also "ground water", no?
pfdietz
No, that "water" is actually hydroxyl groups in minerals.
chrisco255
No it comes out of the tap as water.
mkl
No tap water comes from the mantle.
4 More Comments →
DiggyJohnson
No, it’s completely inaccessible. Unless you are just playing word games, then sure.
ClumsyPilot
Geologically it probably isn’t. If all surface oceans disappeared, some of that water would likely come out to the surface and form new bodies of water, over millions of years.
moralestapia
It's not. The mantle is hundreds of kilometers further down.
Sparkyte
Same question I've got, but I imagine USGS is only considering reachable surface, atmospheric water.
stcredzero
The sphere for all liquid water seems to be close in size to the asteroid Ceres.

https://lightsinthedark.com/wp-content/uploads/2013/06/ceres...

dylan604
But would this sphere of water have enough mass to hold itself together as a sphere in space? Put aside it freezing into a ball of ice as a thought exercise.
rachofsunshine
The freezing-into-a-ball-of-ice is relevant here. A body that small can't hold on to water vapor at anything a human would consider a reasonable temperature; the average velocity of light gases at human-sane temperatures is high enough to overcome their escape velocity. See [1] for a log-log plot of what gases a body can hold onto - even Mars, which is much larger and denser than a Ceres-sized ball of water, has lost most of its water (although other factors like the solar wind are contributors there).

A cold enough body, though, has a low enough vapor pressure that this isn't relevant even over cosmological timescales. That's why Europa can can have a stable icy surface. It's far enough from the Sun (and has a low enough albedo) that it's very very cold (about 100K), and at that temperature ice doesn't sublimate very much.

TLDR: a Ceres-sized ball of water could hold itself together, but only as long as it stayed water. But it wouldn't be able to. Either it'd be cold enough to freeze over at the surface, or hot enough to evaporate into vapor that would escape.

[1] https://en.wikipedia.org/wiki/Atmosphere#/media/File:Solar_s...

littlestymaar
Given that water gets lighter when cooling down right above its fusion temperature, and that ice is a pretty good insulator. You'd have liquid water below an ice crust for a lot of time. It would eventually freeze entirely and be slowly eaten by the Sun's radiations. But that would take a pretty long time (well on a human scale).
rachofsunshine
Yeah, that's why I specified freeze over and not freeze through, although without doing the math I'm pretty sure it'd still freeze through on solar system timescales without radioactive (as in Earth's own mantle's case) or tidal (Enceladus, Europa, possibly Triton and Ganymede) heating.
littlestymaar
Indeed, it will slowly freeze though and evaporate at the same time.
jesprenj
Freezing? Wouldn't it boil instead due to the low pressure?
rachofsunshine
Depends on the temperature. At Earth-like temperatures, yes, it would. The transition between the two is around 175 K, give or take; below about 150 K ice is quite stable in a vacuum even over astronomical timescales; above 200 K it sublimates rapidly. (Surface liquid water is never stable in a vacuum or thin atmosphere regardless.)

The rate of evaporation ramps up exponentially, from ~irrelevant at the bottom of that range to fast at the top. (For a body of this size, any resulting vapor would be quickly lost at these temperatures, so the rate of evaporation is effectively the rate of water loss as well.)

This is why Jupiter can have icy moons (temperature ~100 K), but ice sublimates quickly on Mars (~200 K).

Retric
Going from a liquid to a gas takes energy, which rapidly lowers the temperature of what remains. Net result most of the water freezes without some external energy source. Sublimation then lowers the temperature of the ice until near absolute zero, again unless there’s some external energy source.
dylan604
i knew there would be someone to just try to get out of the answer by failing to just go with the spirit of the question by being pedantic. even my own attempt at dispel pedantry just allowed for even more pedantry.
Dylan16807
I don't know what you wanted.

If you wanted to ask whether that amount can hold together and become spherical, then just by comparing to Ceres doesn't that make it plenty?

It's not crazy to interpret "hold itself together" as more complex and including vapor escape.

ahazred8ta
The sphere of water would have a surface gravity of 0.016 g, 1.6% of Earth's gravity, 1/10th of the Moon's gravity. So yes, it would gravitate into a ball shape, aside from slowly boiling off if it's inside the orbit of Mars (our 32°F Goldilocks Zone) or freezing if it's farther out.
Pat_Murph
The wording of the legend description says all the war in, on and above the earth so we have to assume that is does take it into account.
dredmorbius
Sources say otherwise, see my immediate prior comment.
YVoyiatzis
Water dissolving and removing There is water at the bottom of the ocean
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