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New Zealand's glaciers are shrinking. Startling pictures taken from space 17 years apart show the extent of the retreat of the Tasman, Hooker and Mueller Glaciers in the Southern Alps.
The first picture was taken by a Nasa satellite on December 30, 1990, and the second picture was taken on December 6, 2007.
During the 20th century, the volume of ice in the Southern Alps dropped by 25-30 per cent, glacier length retreated by 38 per cent on average, and the area of ice covering the alps shrank by 25 per cent, glaciologist Dr Trevor Chinn said yesterday.
"It's a result of climate warming. How much you wish to attribute to man-made effects is anybody's guess."
He said the statistics were alarming. "I work on glaciers and my job is disappearing down the river."
There are 3144 glaciers in the Southern Alps. However, some steep glaciers such as the Stocking and Franz Josef glaciers have stopped retreating over the past 30 years. "They are fluctuating about a constant size," he said.
So should we be concerned about the retreating glaciers? "It depends what you want. If you are a boatie, it's great [because the lakes will get bigger]. If you are a climber wanting to go up the valley, it's a nuisance because all the tracks have fallen in. If the big glaciers like Franz Josef and Fox retreat, it will have a bad effect on the tourist trade," he said.
He said there had been regional warming of about 1C since the end of the 19th century.
But Dr Chinn said he didn't have an opinion on whether the shrinking of the glaciers was a good or bad thing.
"As a scientist I don't have an opinion on whether it's good or bad [because that's] emotional, and as a glaciologist, I'd like to see the ice-age return."
