At 12kms, Fox Glacier is the longest of the awe-inspiring New Zealand West Coast glaciers. At its head, soaring peaks of over 3,000m (10,000ft) dominate the vista. These include Aoraki (Mt Cook) and Mt Tasman. This mighty moving river of ice falls 2,600 metres, or a little over 8,000ft, on its journey from the base of the Southern Alps to the West Coast. The second biggest of the West Coast Glaciers is our neighbour the Franz Josef Glacier, at 10kms long. The Franz Josef Glacier flows in a north west direction and travels over quite a steep gradient.New Zealand’s West Coast glaciers are unique and probably the most accessible glaciers in the world, as they terminate amongst temperate rainforest just 250m above sea level. So special is this mountain environment, that it forms part of the South Westland World Heritage Area.
Fox and Franz Josef Glaciers move fast…
The unique combination of climate and shape means that Fox and Franz Josef Glaciers move at approximately 10 times the speed of other valley glaciers around the world. At Fox Glacier this is due to the funnel-like shape of the glacial valley and the huge nevé, the snow accumulation area, at the top of the glacier. Fox Glacier’s nevé is 36 square kms, bigger than the whole of Christchurch City!
…and is currently retreating
Glaciers constantly advance and retreat, held in delicate balance by the accumulation of snow gained in the upper glacier and ice melting in the lower part. An increase in snowfall at the nevé will result in the glacier advancing. Correspondingly, a faster melt will result in the glacier retreating. Overall Fox and Franz Josef Glaciers were advancing from 1985 until 2009, and are curently in a retreating phase.