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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)

#251

Post by lazide »

ahazred8ta wrote: post #169
nwiswell wrote: post #111

Earlier quoted context omitted.

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…

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.

Alas, the atmosphere it could hold would be insufficient to avoid it all vaporizing.

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

#254

Post by px43 »

Mistletoe wrote: post #127
ianburrell wrote: post #117

Earlier quoted context omitted.

It would make Mars warmer. It would melt all the ice and CO2. It would give Mars an ocean. Of liquid rock. This is assuming that it doesn't destroy Mars completely. There might be enough fragments to make Solar System dangerous place and destroy life on Earth. Europa is the size of our Moon. Colliding it with Mars would be similar to the collision that formed our Moon.

But would it stay on Mars? I thought the issue was there was no dynamo in the core, which lets solar winds strip it away. How long would it stay?

At some point I saw a design for a machine you could park at the Lagrange point between Mars and the Sun that would collect solar power and spit out a magnetic field strong enough to deflect enough of the solar winds that we wouldn't need to worry about that.

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

#255

Post by enriquto »

It would be nice to see the "carbon" version of this infography. How much carbon is in the atmosphere as CO_2, in the biosphere as part of living stuff, and buried kilometers underground as gas and oil. Also, how much of that carbon we are pumping per year from underground to the atmosphere+biosphere system, and vice-versa.

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

#256

Post by canibal »

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)

An interesting point, perhaps it's just me, but my initial reaction to this was that, for purposes of comparison, the volume of "usable" or maybe inhabitable land be measured instead, as opposed to the volume of the entire planet including mantle, core, etc. this graphic seems very prone to misinterpretation and usage as a memetic weapon against globalization, as it is.

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

#258

Post by WarOnPrivacy »

rdsubhas wrote: post #234
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…

> The water discovered in the mantle is not in a form familiar to us – it is not liquid, ice, or vapor. Instead, it is trapped inside the molecular structure of the minerals in the mantle rock. IMHO this is not a productive comparison. Hydrogen and oxygen ions inside minerals in rock is far too much of a stretch of imagination to call as water. https://www.earth.com/news/ringwoodite-mineral-confirms-vast...

> Hydrogen and oxygen ions inside minerals in rock is far too much of a stretch of imagination to call as water.

Agreed and to follow that thread to the end: We can't impact that water in a meaningful way.

We can't pollute it in dozens of ecosystem-altering ways.

We can't alter it's ability to host systems that sustain life.

We can't bulk-melt the frozen part & in turn alter the salinity + elevation of a liquid part.

We can't pump dry the parts that we desperately need to remain where they are.

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

#260

Post by veunes »

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's true that while water covers about 71% of Earth's surface, it's just a thin layer compared to the planet's overall volume.
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