Yet, rivers and lakes are the sources of most of the water people use everyday. Fresh surface-water sources, such as rivers and lakes, only constitute about 22,300 cubic miles (93,100 cubic kilometers), which is about 1/150th of one percent of total water. Another 30 percent of freshwater is in the ground. And, of the total freshwater, over 68 percent is locked up in ice and glaciers. Notice how of the world's total water supply of about 332.5 million cubic miles of water, over 96 percent is saline. Of the small amount that is actually freshwater, only a relatively small portion is available to sustain human, plant, and animal life. The left-side bar chart shows how almost all of Earth's water is saline and is found in the oceans. Here is a bar chart showing where all water on, in, and above the Earth exists. Right bar: Only the portion of freshwater residing in surface water (rivers and lakes, etc), snow and ice, and relatively-shallow ground water.Left bar: All water, freshwater and saline, on, in, and above the Earth.If you check back in a million years, no doubt these numbers will be different! You may know that the water cycle describes the movement of Earth's water, so realize that the chart and table below represent the presence of Earth's water at a single point in time. Earth's water is (almost) everywhere: above the Earth in the air and clouds, on the surface of the Earth in rivers, oceans, ice, plants, in living organisms, and inside the Earth in the top few miles of the ground.įor an estimated explanation of where Earth's water exists, look at this bar chart. You've heard the phrase, and for water, it really is true.
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