Japan's Tsunami Rips Icebergs Double the Size of Manhattan

When icebergs break off into the polar seas, scientists usually have to work backwards to figure out why--they try to piece the clues together to figure out what caused an event that already happened. But in March, NASA scientists were able to follow the wake of the Japan tsunami over 8,000 miles, through the Pacific and Southern Oceans, until it snapped off several icebergs from Antarctica--icebergs that together are about as big as not one but two Manhattans (the island, not the drink). 

              Icebergs have long been suspected to have a link with seismic activity, but the creation of icebergs is usually a sudden and mostly unpredictable event, the culmination of lots of pressure over decades or centuries. 

             The Tohoku Tsunami, triggered by the earthquake off the coast of Japan this past March, was a tremendous enough seismic event that cryosphere specialists immediately knew that tracking the wave could provide the first visual proof that this connection exists.

             Tohoku didn't disappoint. Eighteen hours after the tsunami struck Japan, the wave--now only about a foot high--met the Sulzberger ice shelf, a 260-feet-thick sheet of ice extending from Antarctica's land mass towards New Zealand. The Sulzberger ice shelf is no brittle sheet of ice, either, having not moved in nearly half a century.

             Despite the relatively short height, the continuous pressure was massive enough to snap off several huge pieces of ice, one of which is about four by six miles in surface area--roughly the same size as the other chunks combined, and close to Manhattan's 23-square-mile surface area.

            Using satellite imagery (including some help from MODIS), the scientists were able to see the calving, or breaking off, in nearly real-time.  It's definitive proof that a big enough tsunami can have huge effects, not just on the immediate site but even a hemisphere away. 

by "environment clean generations"

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Posted in: iceberg,japan,manhattan,tsunami

Solution to drought: icebergs in dry areas

Towing Icebergs to Fight Drought A 30-ton iceberg could provide water to half a million people for up to a year. A computer simulation shows that this is doable.You may have heard of this scheme before: during periods of serious drought, a huge tugboat or fleet of tugboats could be tethered to an iceberg and hauled to areas where water is scarce, providing drinking water and irrigation stores to stave off famine. The idea was originally floated by an engineer named Georges Mougin in the 1970s, and though it was laughed out of development back then, it’s enjoying a kind of renaissance today. 

            Dassault Systemes, the french software developer, has built a computer model of Mougin’s idea. And after 15 engineers ran the problem through their models, they found that the idea is more or less perfectly feasible. Towing an iceberg from somewhere around Newfoundland to the northwest coast of Africa would only take around five months and could still retain more than 60 percent of the iceberg’s mass. The downside: it would cost about $10 million.

           The simulation accounted for the costs associated with fitting a huge insulating sleeve around a seven-ton iceberg, towing it across the Atlantic via tugboat and kite-sail (at a speed of about one knot), and then distributing the water inland from the coast. A real-world attempt would likely call for a much larger iceberg--a 30-ton iceberg could keep half a million people in drinking water for a year--but the fundamentals, the model says, are sound.

           Since some 40,000 icebergs break away from the polar ice caps each year anyhow, it would make productive use of the fact that we’re all slowly drowning (though few of those ‘bergs are big enough to be worth towing). And it could help deal with serious drought-related human disasters like the one currently unfolding in Somalia.

For his part Mougin is reportedly re-energized by models. At 86, he’s raising funds for a real-world attempt at making his idea a reality.

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Posted in: drought,dry,iceberg,water