15 February 2015
The spectacular Fox Glacier in New Zealand is a very popular tourist attraction on the South Island – Wikipedia estimates that around 1000 people visit per day. Sadly, the Fax Glacier is retreating rapidly, in common with most glaciers as they respond to the effects of climate change. And the effects are dramatic – this pair of images, taken ten years apart, shows just how quickly the glacier is retreating:
As the Fox Glacier retreats, the surrounding hillslopes, which consist of glacial till, lose toe support. In consequence they can slip, although this process is surprisingly poorly investigated. Kerry Leith of TU Munich, pointed out via Twitter this really interesting time lapse video of the glacier retreating, which captures beautifully the creep of the slopes as the snout of the glacier transitions through:
In the early part of the video the slopes on the right side of Fox Glacier are moving (comparatively) rapidly. By the end of the video the glacier has withdrawn from this section, and the slopes have stabilised. Thus, as the glacier snout moves up the valley a wave of slope movement moves with it. This process is being replicated worldwide as glaciers retreat in response to global warming.
The video was compiled by Victoria University of Wellington with the support of Fox Glacier Guides, Department of Conservation, Snowgrass Solutions, University of Canterbury and the Marsden Fund.