James P. Lombard: Weblog Archives
September 21, 2004
Virtual Water
This article in The Guardian explains the idea of "virtual water", or the idea that global trade in grains and food also trades the water used to irrigate or produce the crops. In essence, it makes sense to grow crops in regions of the globe where the climate is best suited for maximum productivity and then traded to water-scarce areas. An excerpt from the article:
Water is present in the food we produce, as well: not as an ingredient, but as an element in its production (remember, 90% of water consumption takes place during food production).
To understand the full implications of that, take the case of the desert regions of the Middle East and North Africa. Those areas entered a period of dangerous strategic water deficits in the early 1970s. If ever there was a good time to suffer a severe water shortage, that was it.
The early 1970s saw the farmers of North America and Europe putting staple grains on the world market at half their production cost. They are still doing that, aided by production and export subsidies that will be difficult to unpick within the next 20 years. It takes so much water to produce those vast mountains of grain that when they are exported they amount, in effect, to a global trade in water. That process can spectacularly fix water shortages. It takes 1,000 tonnes of water to produce a tonne of grain, so by importing grain, water-scarce economies can avoid the stress of trying to develop their own water sources for food production. And because 20% of the world's agricultural production is traded internationally, farmers and traders can move this "virtual water" in volumes and over distances beyond the wildest imaginings of engineers.
The trade in virtual water addresses the biggest water challenge for both individuals and nations facing water scarcity: how to use water to produce enough food. Virtual water also eases the pressure that irrigated agriculture places on water in the environment. It is true that large-scale irrigation is an inefficient use of water, but the trade in virtual water means those regions where irrigation is crucial can put water back into the environment.
Posted by: jlombard at 08:21 AM
Category: Policies
