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Quick Hit: Water ball

by Sarah Scoles

You may have seen this, as it's a few days old, but it's a hit-home visualization, so I thought  I'd share it anyway.

Below, you will see the Earth and a gigantic blue War-of-the-Battleship-Alien-Worlds marble hovering above it. Do not be fooled, though. This is no ordinary War-of-the-Battleship-Alien-Worlds marble. It's the sphere you could make if you gathered up all water on the Earth and, you know, made it into a sphere.

The USGS made us this graphic in order to make us go, at once, "Gee whiz, that's a lot of water!" "Gee whiz, Earth is big!" "Gee whiz, that's not a lot of water compared to how much Earth there is!"

As Gizmodo says, "The sphere includes all the water in the oceans, seas, ice caps, lakes and rivers as well as groundwater, atmospheric water, and even the water in you, your dog, and your tomato plant." Especially your tomato plant.

This sphere has a diameter of 860 miles, or approximately the distance from Brooklyn to Atlanta (this globe shows it spanning some distance in the West and Midwest, but as an Easterner, I have a hard time knowing what "from Salt Lake City to Topeka" really means).

The sphere's volume is approximately 332,500,000 cubic miles, more than Pluto's main moon Charon.

If you took all this water and slopped it across the US (and stopped it from slipping off the coasts and into Canada), the continental states would be covered 90 miles deep in water.

Other cool facts you can glean from the USGS data include

  • 97.54% of Earth's water is salty
  • 0.0001% of it is in you, me, your mom, that tree over there, and chinchillas.
  • 68.6% of the fresh water is in ice caps and glaciers. So it's a good thing they're melting!
  • Psych.
  • Of fresh water that is liquid, 99% is groundwater and thus largely inaccessible.
  • If that liquid fresh water were made into a sphere, it would have a diameter of about 170 miles (20% of the all-water sphere's diameter). However, that diameter means that the sphere would contain only 0.7% of the original sphere's volume.

Mostly, this, to me, makes the point that while we think of Earth as "Earth's surface" because that's the part we walk on and interact with, it's got that whole center going on. We're used to hearing "The Earth's surface is 70% water! Land is in the minority!" and so we (or at least I) in my everyday life go about thinking about how much water there is. But when you compare it to how much stuff is underneath all our feet, and how many miles it takes you to get from East Toyko to West Toyko if you start by going East, there is hardly any water at all.

Check out the USGS's webpage on this topic, which includes a table detailing the water content. You can mess around with the numbers and come up with your own mind-boggling percentages, such as 0.000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000000000000000001% of the water in the world is frozen in wooly mammoths that are frozen in glaciers.



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    As the students it is the prior duty of the students to provide with the enough respect to the teachers. As if they give respect to them they will love to the students and will spend more time in making understandable concept to the students and this will be the better ...
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