This report presents an estimate on the amount of Earth's renewable fresh water that is realistically accessible to humanity.
| Title | Human appropriation of renewable fresh water |
| Publication Type | Journal Article |
| Year of Publication | 1996 |
| Authors | Postel, SL, Daily, GC, Ehrlich, PR |
| Pagination | p. 785-788: 2 fig., 4 tab. |
| Date Published | 1996-01-01 |
| Keywords | evapotranspiration, international level, runoff, water demand, water quantity, water resources, water use |
| Abstract | This report presents an estimate on the amount of Earth's renewable fresh water that is realistically accessible to humanity. Global water balance estimates are derived from the interpolation of climatic, vegetation, and soil information for different geographical zones. The authors examine what portion of this accessible supply humanity now uses directly, diverts into human-dominated systems, or appropriates and, furthermore, by how much human access to water is likely to expand over the next 30 years. They discuss various methodologies and conclude that humanity now uses 24% of total terrestrial evapotranspi-ration (ET) and 54% of runoff that is geographically and temporarily accessible. Greater investments in pollution prevention would free up accessible runoff (AR) to meet rising human water needs while safeguarding ecological functions. Likewise, greater efficiency of water use, changes in agricultural cropping patterns, and the removal of marginal lands from irrigation could help slow the growth of human appropriation of AR. |
| Notes | 33 ref. |
| Custom 1 | 210, 270 |
