Southern Alps glacier loses enough ice to supply NZ with three years' worth of drinking water

A glacier in the Southern Alps has lost enough ice over the past three years to supply New Zealanders with drinking water for the same period.

Brewster Glacier is estimated to have lost 13 million cubic metres of ice in those three years - damage that's putting New Zealand's glacier tourist attractions on a path to extinction.

The glacier, in Mt Aspiring National Park, forms part of the Southern Alps ice storage which has been in decline since the 1970s.

"The staggering thing is that it's just one small glacier," said Victoria University researcher Dr Lauren Vargo.

NIWA climate scientists Dr Andrew Lorrey said he's never seen anything like it in his career.

Overseas, Italy is going to extremes - wrapping a glacier in a 100sqm tarpaulin.

"It's not really a realistic way to stop large-scale glacial melt," Dr Vargo said. "It's just something that can be done for individual glaciers."

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