14 Feb 2012:
‘Virtual Water’ Reliance
Puts Nations at Risk, Study Says
A new study calculates that about one-fifth of all water goes toward the production of crops and commodities for export
, part of a global phenomenon known as “virtual water” that researchers say
Click to enlarge
Arjen Hoekstra and Mesfin Mekonnen, PNAS
The virtual water balance, per country
could place pressure on finite water supplies in some nations. Using worldwide trade indicators, demographic data, and statistics on water use, researchers from the University of Twente in the Netherlands mapped the world’s water footprint, including patterns of trade they say are creating disparities in water use. According to the study, published in the journal Proceedings of the National Academy of Sciences
, many desert and island nations are becoming increasingly dependent on water from other countries, as they import not just food products but the water needed to produce it
. The nations most reliant on this virtual water include the island nation of Malta, which is 92 percent dependent, Kuwait (90 percent), Jordan (86 percent) and Israel (82 percent). Some of the most water-rich nations — including the U.S. and Japan — are also among the biggest importers because the products they import require so much water to produce.
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