One of the few Limits to Growth that actually is a limit rather than some sort of scarcity meme.
However even this should be beatable if some smart people can do the deep dive into the wonder and magic (okay, chemistry and physics) that is H2O.
We'll be hearing about virtual water with increasing frequency, right now there are only 298,000 hits in a Google search....Unfortunately for the credibility of the would-be prophet (moi) the number of hits returned by a Google search has decreased to 244,000.
From the BBC:
While historic winter storms have battered much of the US, California is suffering its worst drought on record. So why is America's most valuable farming state using billions of gallons of water to grow hay - specifically alfalfa - which is then shipped to China?
The reservoirs of California are just a fraction of capacity amid the worst drought in the state's history.
"This should be like Eden right now," farmer John Dofflemyer says, looking out over a brutally dry, brown valley as his remaining cows feed on the hay he's had to buy in to keep them healthy.
In the dried-up fields of California's Central Valley, farmers like Dofflemyer are selling their cattle. Others have to choose which crops get the scarce irrigation water and which will wither.
"These dry times, this drought, has a far-reaching impact well beyond California," he said as the cattle fell in line behind his small tractor following the single hay bale on the back.
"We have never seen anything like this before - it's new ground for everybody."
California is the biggest agricultural state in the US - half the nation's fruit and vegetables are grown here.
Farmers are calling for urgent help, people in cities are being told to conserve water and the governor is warning of record drought.
But at the other end of the state the water is flowing as the sprinklers are making it rain in at least one part of southern California.
The farmers are making hay while the year-round sun shines, and they are exporting cattle-feed to China.
The southern Imperial Valley, which borders Mexico, draws its water from the Colorado river along the blue liquid lifeline of the All American Canal.
It brings the desert alive with hundreds of hectares of lush green fields - much of it alfalfa hay, a water-hungry but nutritious animal feed which once propped up the dairy industry here, and is now doing a similar job in China.
"A hundred billion gallons of water per year is being exported in the form of alfalfa from California," argues Professor Robert Glennon from Arizona College of Law.
"It's a huge amount. It's enough for a year's supply for a million families - it's a lot of water, particularly when you're looking at the dreadful drought throughout the south-west."...MORE