While the volume of water contained in Earth’s oceans seems like a lot, and it certainly is on a human scale, both the ocean and atmosphere are merely thin shells surrounding the solid parts of our planet. If every drop of water in the world was collected in a sphere, it would be just 869 miles in diameter. The illustration above shows a comparison of the volume of water and the size of Earth. The ball of water seems shockingly small, with a volume of only 338 million cubic miles (1.41 billion km3).
Water on the left, air on the right
via The Resilient Earth.