The latest study into climate change appears to confirm what environmental experts have long suspected; that the world's temperature is rising.This content was published on September 7, 2000 - 17:15
The study, compiled by an international team of researchers, compared historical weather records from all over the world. They show that temperatures are rising, and affecting the way lakes and rivers freeze.
The study also shows that the most significant changes have taken place in the past 150 years, suggesting a correlation with the industrial revolution, which vastly increased emissions of man-made gases into the atmosphere.
Here in the Alps, experts from the World Glacier Monitoring Service have for years been observing the behaviour of the alpine ice fields. Glaciologist Martin Hoelzle, of the Swiss Federal Institute of Technology, says their research seems to support the global warming theory.
"What we can say is that the glaciers, especially in the Alps, are retreating very fast. They are losing a lot of mass."
The upper Grindelwald glacier is a popular attraction for visitors to the Bernese Alps, but Hoelzle says it is a prime example of how glaciers are shrinking.
"Just 15 years ago the ice came right down to the trees," he said. "Now we have to climb 980 steps up the rock to reach it. In 1850, you could see the glacier from the village of Grindelwald itself. As it crept down, it knocked over trees in its path."
Hoelzle has no doubt that climate change is responsible for the glaciers' retreat. "It is certain that the climate is changing, and getting warmer," he said. "What's more difficult to say is whether human activity is responsible. But there is very strong evidence to show that what we do is at least partially to blame."
So could alpine glaciers disappear altogether? Martin Hoelzle thinks this is unlikely. "Certainly a major glacier like the Aletsch glacier will survive the 21st century," he said. "Nevertheless its retreat is dramatic; it has lost around 2.5 square kilometres since 1815 - this is a huge loss of mass."
The consequences of shrinking glaciers could be severe. "In central Asia glaciers are the primary source of fresh water in summer," said Hoelzle. "If they carry on shrinking, the reduced supply could cause serious drought. And here in Switzerland they supply the hydro-electric power stations with water in summer, so here too we could have problems."
But what worries Hoelzle most is what the glaciers' retreat is telling us about the state of the world's climate.
"The glaciers are an indicator of climate change. If they are shrinking it means the climate is changing. And that means our entire environment and weather system will change, with possibly very severe consequences, such as increased storms and flooding."
by Imogen Foulkes
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