3 Answers

http://ga.water.usgs.gov/edu/earthhowmuch.html

Just how much water is there on (and in) the Earth? Here are some numbers you can think about:

If all of Earth's water (oceans, icecaps and glaciers, lakes, rivers, ground water, and water in the atmosphere was put into a sphere, then the diameter of that water ball would be about 860 miles (about 1,385 kilometers) across, a bit more than the distance between Salt Lake City, Utah to Topeka, Kansas. The volume of all water would be about 332.5 million cubic miles (mi3), or 1,386 million cubic kilometers (km3). The picture at the top of this page illustrates this. A cubic mile of water equals more than 1.1 trillion gallons. A cubic kilometer of water equals about 264 billion gallons.
About 3,100 mi3 (12,900 km3) of water, mostly in the form of water vapor, is in the atmosphere at any one time. If it all fell as precipitation at once, the Earth would be covered with only about 1 inch of water.
The 48 contiguous United States receives a total volume of about 4 mi3 (17.7 km3) of precipitation each day.
Each day, 280 mi3 (1,170 km3)of water evaporate or transpire into the atmosphere.
If all of the world's water was poured on the United States, it would cover the land to a depth of 90 miles (145 kilometers).
Of the freshwater on Earth, much more is stored in the ground than is available in lakes and rivers. More than 2,000,000 mi3 (8,400,000 km3)of freshwater is stored in the Earth, most within one-half mile of the surface. But, if you really want to find freshwater, the most is stored in the 7,000,000 mi3 (29,200,000 km3) of water found in glaciers and icecaps, mainly in the polar regions and in Greenland.

According to the book of Genesis, water covered the whole of the Earth and wiped out all humans except Noah and his family. Yes, some people actually believe this. ( Not me).

Trillions upon trillions of tons, just in the oceans that cover over 70% of our world.

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