Is climate change for real? Are all glaciers in the world retreating at the same rate? A recent report by the Indian government suggests that the glaciers in the Himalayas may be bucking the warming trend, but how are glaciers fairing elsewhere?

Switzerland is home to snow-capped mountains, has clean air and is a playground for winter sports. But for how long will this ice last? Global warming is beginning to make its ominous presence felt here at the 23 kilometer long Aletsch Glacier, the longest in the Alps. The melt has begun in the last 150 years the glacier has retreated by about three kilometres.

"What we have observed is that glaciers retreat due to climate impact or the global warming which forces additional melt and glaciers start to retreat," said Andreas Bauder, a Glaciologist at the Swiss Federal Institute of Technology, Zurich.

Each glacier it seems has its very own personality, each responding to climate change differently. To better understand the Aletsch we took an aerial look at this 120 square kilometres icy stretch.

On the ground, glaciologists use simple tools like a long pole and a drill to track the health of glaciers. It is hard work and glaciers don't always reveal their deep secrets easily. Yet, understanding its dynamics is important as the glacier literally supports the livelihoods of thousands of people in the Valley.

The Aletsch glacier, the longest in the Alps, is retreating fast. If the Copenhagen talks don't come with a solution for climate change this glacier may recede and disappear in times to come.