Virtual water

Water consumption to produce one kg beef
Water consumption to produce one kg beef
Image Credit: C. Studer
Water consumption to produce one cup of coffee
Water consumption to produce one cup of coffee

Virtual water was defined at the beginning of the 1990s by Professor J.A. Allan as „water embedded in commodities“ [6].

Virtual water is an important tool for calculating the real water consumption of a country.

Water consumption is the sum of domestic consumtion and virtual water import (import of products) minus virtual water export (export of products) of a country. The global volume of virtual water flows related to the international trade in commodities is 1.600 km3/yr.

About 80% of these virtual water flows relate to the trade in agricultural products, while the remainder is related to industrial products.