Thursday, 18 September 2008
Glaciers are spiritual places
The Franz Josef Glacier, like all the other Glaciers in New Zealand, is rapidly shrinking. Photo: Bob McKerrow
To stand on a glaciers and feel its power as it grinds, flows, shakes and rests, is to feel power like no other. To see glacial mills, worn mountain sides and sweeping morraines is to observe the work of glaciers over millions of years. They are spiritual places and for me, places of pilgrimage.
I have been visiting the Tasman, the Fox, the Franz Josef, Brewster and Bonar Glaciers since 1966 and in just over 40 years they appear to have almost halved.
Most of New Zealand's glaciers are now the smallest they have been since records began - and they continue to shrink at a rapid rate.
The National Institute of Water and Atmospheric Research, which made the discovery, said global warming was the main culprit.
WARMING SIGN: Marion Glacier in Arawata Valley has recently withdrawn from its proglacial state. Most of New Zealand's glaciers are the smallest they've been since records began.Photo:Trevor Chinn
Between April last year and March this year, glaciers in the Southern Alps lost about 2.2 billion tonnes of permanent ice - the equivalent in weight to the top section of Mt Taranaki. It is the fourth highest annual loss since monitoring began 32 years ago.
Graham Saddle which connects the Franz Josef Glacier, via the Rudolf Glacier, to the mighty Tasman Glacier. Photo: Bob McKerrow
The total ice for the glaciers now comprises an estimated 44.9 cubic kilometres - the lowest on record. The volume of ice dropped by 50 per cent during the last century.
Niwa principal scientist Jim Salinger said glaciers were fed by snow, but because of the La Nina weather system over New Zealand, more easterly winds and warmer than normal temperatures during the period, there was less snow in the Southern Alps and more snowmelt.
Peaks at the Head of the Tasman Glacier. Photo: Bob McKerrow
Dr Salinger said while the glaciers were sensitive to changes in wind and precipitation as well as temperature, global warming was a big factor in their shrinking.
"It's one of the clearest signs that our climate is warming and that [the shrinkage] is a definite physical response. To have that amount of melting you would have to reduce the precipitation at least by a half or more or warm a degree," he said.
The retreating Tasman Glacier. Photo: Bob McKerrow
"They are definitely a sign of warming. There is no doubt about it. You get a very rapid loss of snow and ice and that's what's been happening."
"We know that precipitation has not gone down in the Southern Alps. In the last quarter of a century it's gone up. So to make them retreat you've got to have more melting, which is higher temperatures.
"This is certainly a definite sign of warming in the New Zealand area."
Niwa has surveyed 50 glaciers in the Southern Alps for the past 32 years, recording the height of the snowline at the end of each summer. On average the snowline this year was 130 metres above where it would need to be for the glaciers not to shrink, Dr Salinger said.
It was unlikely the glaciers would disappear entirely, as that would require a temperature rise of 7 degrees Celsius and no snow even at the top of our highest mountain, Mt Cook.
But they would continue to retreat. Another sign of warming were 12 glacial lakes, including ones at Marion Glacier and Tasman Glacier.
Looking from Castle Rocks Hut across the Franz Josef Glacier to the Southern Alps of New Zealand. Photo: Bob McKerrow
What moves me most is mountain landscapes and my dream of being a snow flake wafting from the sky. To fall on a mountain pass or a col, or even top of a mountain peak. To later to be part of a bergschrund, a snowy arete, a snow field, a neve, a glacier, a crevasse and in my anger and power, an avalanche. And then when I melt, that long trip down the river to the sea. The processes of snow, ice, glaciers, and mountain geology fascinate me and have drawn me back in awe time and time and time again. While reveling in the beauty of the mountains it reminds me our life on this earth is as ephemeral as a snowflake.
The Franz Josef Glacial neve taken from Almer Hut. The Southern Alps of New Zealand in the background. Photo: Bob McKerrow
I once could ski like the wind down mountainsides in New Zealand, France, Austria, Italy and Switzerland. I often repeat the runs in my mind. What keeps me traveling and working these days is the anticipation of seeing something new and the sense of awe evoked by architecture, landscapes, people and their cultures. To close my eyes and to look back at the history behind these special places, provides a sense of place and purpose in my life. Frequently the kaleidoscope of contrasts, from awe to awfulness, between pomp, power and poverty, and death; which I see almost daily in my work, wearies me greatly. Every year I return to New Zealand and visit the mountains to restore by soul, and rest my burnt body.
The Waiho River Valley which was covered by ice 15,000 years ago.
Special thanks to Tom Cardy of The Dominion Post to quote from his recent article.