We think of Earth as watery – the blue planet. But how much water is there, and where exactly is it held?

As well as the obvious places like the oceans, large stores of water can be found in some surprising corners of the planet – even beneath the world’s driest deserts.

It's difficult to imagine how much it all adds up to, but the Earth Unplugged team have a thirst for answers, and so decided to tot up the numbers for our planet’s most precious resource.

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