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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)

#12
post #9

Wouldn't a cube be a better choice for visualizing volume? A more complete version would do it alongside with minerals, biomass, etc

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 only gets worse as we graduate from cylinders to spheres.

We can all visually see which sphere is bigger, but cannot come close to estimating how much bigger one is than another.

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

#13

Can’t help but want to build that. Apparently all the mined gold in the world would fit inside a 5 m diameter sphere. Spheres are suspicious in hiding weight.

I've heard something like this before, but 5m is too small. The gold council reckons it's a little larger than that: https://www.gold.org/goldhub/data/how-much-gold

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

#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)

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

#18
post #5

The height of the sphere isn’t easy to visualize, should over lay height of water over Americas area

I'm trying to visualize the amount of water here, but it's hopeless unless an elementary student can calculate how many oil drums it would fill or football fields it would cover to a depth of one yard.

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

#20

Can’t help but want to build that. Apparently all the mined gold in the world would fit inside a 5 m diameter sphere. Spheres are suspicious in hiding weight.

The World Gold Council says:

> If every single ounce of this gold were placed next to each other, the resulting cube of pure gold would only measure around 22 metres on each side

So that can't possibly be right, you must be off by a factor of 10 or so at least—Wolfram Alpha says a 30m diameter sphere.

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