The World's Air and Water Supply, Visualized

[Demeter]

http://www.nakedcapitalism.com/2008/02/world-water-visualized.html

Left: All the water in the world (1.4087 billion cubic kilometres of it) including sea water, ice, lakes, rivers, ground water, clouds, etc.

Right: All the air in the atmosphere (5140 trillion tonnes of it) gathered into a ball at sea-level density. Shown on the same scale as the Earth.

[tridim]

1. Wow!

The "Earth is 70% water" statement is kind of misleading looking at that graphic.

It's crazy to imagine that that tiny ball of water was the soup that all of Earth's life arose from.

[edhopper]

2. The world is not 70% water.

70% of the Earth's surface is covered by water. There is a BIG difference.
The depth of that water is a small fraction of the Earth's diameter. That is why so little of the earth is water.

[tridim]

3. Right, that's why I posted..

If you ask the average person how much of the Earth is water, they'll say 70%. People tend to think surface, and not volume.

Few realize how precious and rare water actually is.

[Demeter]

4. When You Look At It This Way, It's Possible That All Our Water

came from comets, as has been hypothesized.

[Canuckistanian]

5. That's amazing

Especially the size of the water ball, but I guess it makes sense.

But I knew that our atmosphere was thin on that scale. Astronauts have said that they can see the thickness of the atmosphere from space and it's a really, really thin covering.