The unusual case of the 'growing' glaciers

Description

Around the world, from Greenland to Antarctica, glaciers are melting and retreating. The cause? Rising temperatures.

But between 1983 and 2008 some New Zealand glaciers bucked the trend – they were getting thicker and longer.

Franz Josef Glacier on the West Coast was a stand-out – it regained half the ground it had lost in the previous seven decades. This was good news for tourists who flocked to see the glacier, but it left glaciologists from NIWA and Victoria University of Wellington wondering. What was going on? What was causing some glaciers – but not others – to grow?

The answer, says Andrew Mackintosh from Victoria University’s Antarctic Research Centre, was a period of cooler temperatures around New Zealand and the Tasman Sea.