How Much Water is on The Earth -- Really?

This drawing shows the size of a sphere that would contain all of Earth's water in comparison to the size of the Earth. The blue sphere sitting on the United States, reaching from about Salt Lake City, Utah to Topeka, Kansas, has a diameter of about 860 miles (about 1,385 kilometers) , with a volume of about 332,500,000 cubic miles (1,386,000,000 cubic kilometers). The sphere includes all the water in the oceans, seas, ice caps, lakes and rivers as well as groundwater, atmospheric water, and even the water in you, your dog, and your tomato plant. Image courtesy: USGS/Public Domain

I know, I know. I always seem to be harping on water - it's availability; drinkability; distribution; conservation vs pollution; use vs misuse; and, on and on ad nauseum. I have been saying for a long time now that water will become the new currency; and, if you can't afford to pay, you die of thirst - that simple.

It's hard for those of us who are still able to turn on a tap and have clean, clear drinkable flow right into our glasses to believe that lives have been lost in the effort to obtain good, clean drinking water. Click here, or here or even here.

Maybe this will put some things into perspective.

While it looks like the planet's surface is covered mostly in water, the fact is there is very little water on this planet when you compare it to the size of the planet as a whole. The USGS created this image to give us a little perspective.

USGS states, "About 70 percent of the Earth's surface is water-covered, and the oceans hold about 96.5 percent of all Earth's water. But water also exists in the air as water vapor, in rivers and lakes, in icecaps and glaciers, in the ground as soil moisture and in aquifers, and even in you and your dog. Still, all that water would fit into that "tiny" ball. The ball is actually much larger than it looks like on your computer monitor or printed page because we're talking about volume, a 3-dimensional shape, but trying to show it on a flat, 2-dimensional screen or piece of paper. That tiny water bubble has a diameter of about 860 miles, meaning the height (towards your vision) would be 860 miles high, too! That is a lot of water."

It may be a lot of water, but almost all of it is not usable for us. Over 96% is saline water in the oceans, and of the fresh water that's left, most of that is locked up in ice at the poles, is underground were we don't reach it, or is in the atmosphere.

Perhaps this will give us some perspective on how truly precious a resource water really is. Please conserve whenever possible and don't pollute this diminishing resource.