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

usgs.gov

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

#21

Post by AnimalMuppet »

margalabargala wrote: post #12
mulhoon wrote: post #9

Earlier quoted context omitted.

Why?

Humans are notoriously terrible about estimating volumes when things are curved and volume functions are exponential. A great example of this done in 8th grade science classes across the US is to put 100ml of water in a 100ml graduated cylinder, 150ml in a 1L beaker, and ask the class which has more. Humans are awful at estimating how much volume the increased radius adds, and usually will say the 100ml. The problem…

Volume functions are not exponential. They are polynomial.

(Fair point that people are lousy at estimating even polynomial functions, though...)

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

#23

Post by moralestapia »

umvi wrote: post #16

> 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)

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.

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

#27

Post by stcredzero »

umvi wrote: post #16

> 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)

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...

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

#28

Post by maushu »

myself248 wrote: post #22

Turn Randall Munroe loose on this idea and be prepared for unspeakable devastation as a tsunami of Lovecraftian proportions wreaks havoc on the planet...

He already did it with a 1km diameter ball (https://what-if.xkcd.com/12/) and the destruction was terrifying. Please keep him away from these other bigger water balls.

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

#30

Post by rmah »

Just a few quick calculations to make it more relatable...

They say the smallest sphere of freshwater lakes and rivers amounts to 93,113 cu km. There are 1 bil cu m per cu km. With a global population of 8.2 bil people, that comes to 11,355 cu m per person. That's a 22.5 meter wide/deep/tall cube (or about 7 or 8 stories tall building).

If we use the sphere that includes groundwater, 10,633,450 cu km. Then we end up with 1,296,762 cu m or a 109m wide cube per person.

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