Human appropriation of renewable fresh water
Postel, S.L.; Daily, G.C.; Ehrlich, P.R.
Science 271(5250): 785-788
1996
ISSN/ISBN: 0091-7729 DOI: 10.1126/science.271.5250.785Document Number: 310035
Humanity now uses 26 percent of total terrestrial evapotranspiration and 54 percent of runoff that is geographically and temporally accessible. Increased use of evapotranspiration will confer minimal benefits globally because most land suitable for rain-fed agriculture is already in production. New dam construction could increase accessible runoff by about 10 percent over the next 30 years, whereas population is projected to increase by more than 45 percent during that period.