Not much
How Much Water is On Earth?
In this illustration, the blue ball represents the volume of all the water on earth, relative to the size of the earth. The tiny speck to the right of the blue ball represents Earth’s fresh water. CREDIT: David Gallo/WHOI
If Earth was the size of a basketball, all of its water would fit into a ping pong ball.
How much water is that? It’s roughly 326 million cubic miles (1.332 billion cubic kilometers), according to a recent study from the U.S. Geological Survey. Some 72 percent of Earth is covered in water, but 97 percent of that is salty ocean water and not suitable for drinking.
“There’s not a lot of water on Earth at all,” said David Gallo, an oceanographer at the Woods Hole Oceanographic Institution (WHOI) in Massachusetts.