Although water covers approximately sixty-seven percent of the Earth’s surface, less than three percent is fresh water. Accounting for fresh water locked in glaciers, icecaps, or otherwise inaccessible, less than a tenth of a percent of the Earth’s water is available for human consumption. Pollution, population growth, and wasteful irrigation practices they are contributing to a worldwide water shortage. When the clear precious liquid becomes scarce, countries begin to assert claims on fresh water supplies. As a result, drinkable water has become a region of conflict that could eventually lead to greater hostilities between nations.
What is not a cause of a world-wide water shortage?