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All of Earth's water in a single sphere (2019)

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Re: All of Earth's water in a single sphere (2019)

#221

Post by DaoVeles »

jvanderbot wrote: post #170
sfink wrote: post #59

I long assumed that the Earth is a "water planet" because water is mostly what you see from a distance. It wasn't until I did the math that I realized that is really about wet rocks in space vs dry rocks in space. Earth isn't made of water, it's just a damp rock. Or a bowling ball that you squirted a dozen times with a spray bottle.

There are moons out there that are more like giant snowballs - so much water that it dwarfs even our reserves.

There was an old sci-fi trope that the reason aliens attack earth is to get at our water.

The problem with that was, 1. there are better sources of water (the oort cloud) and 2. they aren't stuck in an gravity well.

Re: All of Earth's water in a single sphere (2019)

#222

Post by nvader »

nwiswell wrote: post #111
oorza wrote: post #98

Earlier quoted context omitted.

Closer to a bowling ball that picked up a drop of beer from your hands.

This didn't sound right, so I did the math. The volume of all water is 1,386,000,000 km^3, which is then 1.386e+21 liters, or right about the same number of kilograms. The mass of Earth is about 5.972e+24 kg. So the percent fraction by mass is 0.0232%. A "drop" is typically estimated at 1/20th of one mL, which is then 0.05 grams. We can estimate the mass of a small-ish bowling ball at 5kg, or 5000 grams. 0.05 / 5000…

A dash.

Re: All of Earth's water in a single sphere (2019)

#223

Post by globular-toast »

berkes wrote: post #220
hn_throwaway_99 wrote: post #178

Earlier quoted context omitted.

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 in…

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)

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).

Re: All of Earth's water in a single sphere (2019)

#224

Post by autoexec »

berkes wrote: post #220
hn_throwaway_99 wrote: post #178

Earlier quoted context omitted.

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 in…

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)

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?

Re: All of Earth's water in a single sphere (2019)

#225

Post by vixen99 »

dredmorbius wrote: post #159

NB: The infographic and articles are based on a 1993 publication. More recent research, from about 2017, suggests that there's about as much water in Earth's mantle as in all the oceans, so we either need another drop roughly the volume of the first, or the second drop should be greatly expanded. See: "There’s as much water in Earth’s mantle as in all the oceans" (2017) https://www.newscientist.com/article/2133963-th…

Seems that Jules Verne (1867) in 'Journey to the Center of the Earth' was onto something when he invented his subterranean ocean.

Re: All of Earth's water in a single sphere (2019)

#227

Post by hoseja »

sfink wrote: post #59

I long assumed that the Earth is a "water planet" because water is mostly what you see from a distance. It wasn't until I did the math that I realized that is really about wet rocks in space vs dry rocks in space. Earth isn't made of water, it's just a damp rock. Or a bowling ball that you squirted a dozen times with a spray bottle.

It is quite incredible that there is just enough water for a continuous ocean and also dry land, not either just a couple ponds or a waterworld.

Re: All of Earth's water in a single sphere (2019)

#228

Post by Lautzi »

kevinkeller wrote: post #32

Largest ocean in our solar system isn't even on Earth, apparently: > ... Ganymede’s ocean is even bigger than Europa’s—and might be the largest in the entire solar system. “The Ganymede ocean is believed to contain more water than the Europan one,” he says. “Six times more water in Ganymede’s ocean than in Earth's ocean, and three times more than Europa.” https://www.scientificamerican.com/article/overlooked-ocean-..…

The largest ocean in the solar system actually is on Jupiter [1]. The gas planet has an absolute massive amount of liquid hydrogen on its "surface". But yeah, liquid hydrogen isn't water, so it might be the biggest ocean, but not the biggest ocean made out of water in our solar system :).

[1]: https://science.nasa.gov/jupiter/jupiter-facts/ (Under "Structure")

Re: All of Earth's water in a single sphere (2019)

#229

Post by hoseja »

Sparkyte wrote: post #76
kevinkeller wrote: post #32

Largest ocean in our solar system isn't even on Earth, apparently: > ... Ganymede’s ocean is even bigger than Europa’s—and might be the largest in the entire solar system. “The Ganymede ocean is believed to contain more water than the Europan one,” he says. “Six times more water in Ganymede’s ocean than in Earth's ocean, and three times more than Europa.” https://www.scientificamerican.com/article/overlooked-ocean-..…

We could probably terraform Mars if we crashed Europa into Mars.

If we could crash Europa into Mars we'd have capability to terraform Mars in a more reasonable manner.

Re: All of Earth's water in a single sphere (2019)

#230

Post by sverhagen »

card_zero wrote: post #215
hn_throwaway_99 wrote: post #178

Earlier quoted context omitted.

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 in…

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…

>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.

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