Sunday, June 5, 2011

Icebergs: Delivering Fresh Water

Towing icebergs to places desperate for water is something of a non-urban myth. The idea sounds good on the surface. The planet is running short of freshwater, and gloomy forecasts predict a 30 percent rainfall decrease around the globe. Meanwhile, tens of thousands of big, purely freshwater icebergs crack off Greenland and Antarctica every year, only to drift into warmer waters and melt.
The notion of harnessing these massive, glassy natural resources is hardly new. In 1773 Captain James Cook brought small icebergs aboard The Resolution to replenish fresh water supplies. Towing bergs north or south has been seriously talked about in this century since the 1950s.
Unfortunately, every time a visionary entrepreneur floats a plan for navigating all that solid freshwater to parched markets, the H2O innovator is stymied by 1) the high cost of the towing and 2) the unacceptable amount of ice lost along the route.
Still, new iceberg theorists pop up every few years. The latest proposal comes from a University of Cambridge professor of ocean physics named Peter Wadhams. Wadhams claims to have partners in Canada and France who want to use tugboats to lug bergs from Newfoundland to the Canary Islands.
“It would be very nice to try it out and see if it works,” said Wadhams.
The group, which is of course looking for investors, bases its optimism on a hi-tech virtual map study illustrating the combination of ocean currents and winds, the anticipated melt rate and the tugboat’s fuel consumption. Coating the underside of the iceberg with an “insulating geotextile material” to reduce melt rate is a new twist on previous notions of wrapping them in sailcloth or Kevlar.
A team of 15 at Dassault Systems, a French software company, put the virtual imaging together. It estimated that a 7 million ton iceberg would take 141 days to reach the Canaries, and would lose 38 percent to melting. A test is estimated to cost upward of $10 million.
Five years ago, Britain’s biggest water supplier—Thames Water, which delivers to 13 million people—announced it was considering a plan to drag bergs from Greenland or northern Scandinavia across the North Sea. After factoring in costs, disruption of shipping lanes and that damn problem of ice melting as it reaches warmer climes, the plan was quietly dropped.
In 1977, scientists from 18 nations gathered at the International Conference on Iceberg Utilization at Iowa State University trotted out a similar idea. The event was organized and paid for by a nephew to the king of Saudi Arabia, a place desperate for new water sources, then and now.
The idea of Prince Mohammed al Faisal—and his Iceberg Transport International company—was to wrap a 100-million-ton iceberg off Antarctica in sailcloth and plastic and tow it with a fleet of tugboats back to the Arabian Peninsula. The trip was estimated to take eight months and cost $100 million.
At the time, the math suggested that the high costs would still be cheaper than desalinating water close to home, typically the Saudi’s primary access to fresh water. It was also thought that the American public—sucker that it is!—would pay for unique bottled iceberg water. To support his dream, Prince Faisal delivered a mini iceberg from Alaska to Iowa, by helicopter, plane and truck, where it was chipped and put into cocktails.
A Time magazine report of the day quoted a representative of the U.S. Army Cold Regions Research and Engineering Laboratory who was hardly optimistic: “Once you get north of the equator, you’ll have nothing but rope at the end of your tow.”
But maybe one day will be the ultimate cold day in …. and towing icebergs will finally make sense.

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