Japansk tsunami fik Antarktis til at kælve

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Selv efter at have vandret 13.000 kilometer kunne bølgerne anrette skader

The tsunami caused by the 11 March Tohoku earthquake in Japan crossed the Pacific and broke off large chunks of ice from Antarctica, a study has shown according to BBC online.

Satellite photos show huge icebergs were created when the tsunami hit West Antarctica’s Sulzberger Ice Shelf. This caused 125 sq km of ice to break off – or calve – from a shelf front that has remained stable for the past 46 years.

The work, by a US team, is published in the Journal of Glaciology.

The waves generated by the 9.0 Magnitude earthquake in Japan travelled about 13.000 km across the Pacific Ocean before reaching the Sulzenberger Ice Shelf, causing ice to break off and float into the sea.

The largest of the icebergs measured 6,5 km by 9,5 km and 80 meter in thickness.

The swell was estimated to have been just 30 cm high when it reached the Sulzberger shelf. But the researchers say that over a period of hours to days, the dispersed waves caused repeated flexing of the ice, “fatiguing” the shelf and causing it to fracture.