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About the Campaign Water is Life Save Water Resources Quiz Gallery |
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| EARTH WATER SUPPLY |
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From the graphs above we can see the proportions of the Earth’s water supply. About 97% of all water is in the oceans, and the remaining three percent is Freshwater. The majority of the latter, about 69%, is locked up in glaciers and icecaps, mainly of Greenland and Antartica; and the remaining, almost all of it is below our feet as ground water. No matter where on Earth we stand, chances are that, at some depth, the ground below is saturated with water. Of all the freshwater on Earth, only about 0.3% is contained in rivers and lakes, known as surface water. Considering that most of the water we use in everyday life comes from rivers, we make use of a tiny portion of the available water supplies. The vast majority of the fresh water available for our uses is stored on the ground we stand.
From the chart below we can statistically envision the water supply of the world and the proportion that each source contributes towards its existence.
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One Estimation of Global Water Distribution
Water Source |
Water Volume (in cubic meters) |
Water Volume (in cubic kilometers) |
Percent of Freshwater |
Percent of total water |
| Oceans, Seas, & Bays |
321,000,000 |
1,338,000,000 |
-- |
96.5 |
| Ice caps, Glaciers, & Permanent Snow |
5,773,000 |
24,064,000 |
68.7 |
1.74 |
| Groundwater |
5,614,000 |
23,400,000 |
-- |
1.7 |
| Fresh |
2,526,000 |
10,530,000 |
30.1 |
0.76 |
| Saline |
3,088,000 |
12,870,000 |
-- |
0.94 |
| Soil Mositure |
3,959 |
16,500 |
0.05 |
0.001 |
| Ground Ice & Permafrost |
71,970 |
300,000 |
0.86 |
0.022 |
| Lakes |
42,320 |
176,400 |
-- |
0.013 |
| Fresh |
21,830 |
91,000 |
0.26 |
0.007 |
| Saline |
20,490 |
85,400 |
-- |
0.006 |
| Atmosphere |
3,095 |
12,900 |
0.04 |
0.001 |
| Swamp Water |
2,752 |
11,470 |
0.03 |
0.0008 |
| Rivers |
509 |
2,120 |
0.006 |
0.0002 |
| Biological Water |
269 |
1,120 |
0.003 |
0.0001 |
| Total |
332,500,000 |
1,386,000,000 |
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100% |
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Source: Gleick, P. H., 1996: Water resources. In Encyclopedia of Climate and Weather, ed. by S. H. Schneider, Oxford University Press, New York, vol. 2, pp.817-823.
Thus we see that the water available to us in the world is 1,386,000,000 (1 billion, three hundred and eighty six million cubic kilometers) out of which ground water composes of merely a 23,400,000 (twenty three million, four hundred thousand cubic kilometers), a 1.7% of the total water supply. However it is worth noting that this small source of water supply makes up 99% of total usage of water, the rest 1% coming from other sources. Therefore though the water supply may be abundant and seem perpetually renewable, the amount that is fit for human utilization and consumption is limited.
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