12 May 2015

Watch 2 years of glacier retreat in 15 seconds

by Tom at Franz Josef Glacier Guides

Incredible footage of Mother Nature on the move.

A time-lapse video released by the Franz Josef team shows astounding changes that have occurred to Franz Josef Glacier over the last two years.

Footage shot from remote webcams between December 2012 and January 2015 condenses 25 months of glacier movement into less than a minute and gives a visual explanation of how much the glacier is changing.

The web cams are a joint initiative between Franz Josef Glacier Guides and The Department of Conservation and assist the operations team at Franz Josef to determine the status of the glacier for the daily heli hike trips.

So, what does a glacier do over 25 months?

Well, quite a lot.

Cave at Franz Josef Glacier

Have a look at the appearance of a “cave” in the terminal face of the glacier. You can see that the tongue of the glacier becomes unstable and subject to rockfall and ice collapse. This is the reason we no longer hike over that section of the glacier.

When the video is sped up you get an idea of not only the rate of retreat of the glacier, but also the loss of ice volume and depth that has occurred over 25 months.

River of ice

In the second part of the video, sped up time lapse footage gives an incredible visual demonstration of what we mean we say the glacier is always on the move. On our trips the guides talk about a glacier being a river of ice. This video shows what we mean; you can see the icy flow cascading down the steep mountain, just as a river flows.

Franz Josef Glacier, New Zealand

A few facts on Franz Josef Glacier movement:
  • Since the late 1880’s Franz Josef Glacier has had an overall retreat of around 3 kilometres.
  • There have been a number of advance periods during this time, with the most recent advance occurring between 1983 and 1999.
  • Since 2008, Franz Josef Glacier has been in a period of retreat, and has lost around 800 metres of length.
  • Glaciers advance and retreat as a part of a natural cycle.
  • A glacier is dependent upon a fine balance of accumulation and melting. If there is high accumulation (snowfall) then the glacier grows, and if there is high melt then the glacier retreats.
  • Franz Josef Glacier is a highly sensitive glacier. So, in theory a few massive snowfall years could trigger another period of advance.
There’s no denying that Franz Josef Glacier looks very different to how it did two years ago.

Similar changes are occurring to our neighbour Fox Glacier and many other glaciers throughout the Southern Alps. At Franz Josef Glacier Guides, we reckon it’s so important to educate people on how a glacier works and get some discussion going on what is happening to this changing landscape, and why.

Whether it’s climate change or the natural cycle of the glacier, the important thing is that people are talking about what is happening to this precious environment. Don't you think you should come and see it for yourself?