Sunday, July 27, 2008

Kilimanjaro's Disappearing Glacier Trick

Global warming and Kilimanjaro: where have Kili's glaciers gone?

On August 3rd I will depart for my 8th trip to climb Kilimanjaro located in East Africa in the country of Tanzania. Follow along by signing up for our daily trip dispatches.

Much has been written and discussed regarding the retreating glaciers of Africa's highest mountain. There have been several extensive studies performed recently on the mountain in hopes of gaining some insight as to how quickly they are disappearing as well as whether it can be exclusively blamed on global warming.

Of the 19 square kilometres of glacial ice to be found on Africa, only 2.2 square kilometres can be found on Kilimanjaro. Unfortunately, both figures used to be much higher.

Kili’s famous glaciers have shrunk by a whopping 82% since the first survey of the summit in 1912. Even since 1989, when there were 3.3 square kilometres, there has been a decline of 33%. At that rate, say the experts, Kili will be completely ice-free within the next decade or two.‘We found that the summit of the ice fields has lowered by at least 17 metres since 1962,’ said Professor Lonnie Thompson of Ohio State University. ‘That’s an average loss of about a half-metre (a foot and a half) in height each year.’

The big question, therefore, is not whether Kilimanjaro’s glaciers are shrinking, but why – and should we be concerned? Certainly glacial retreats are nothing new: Hans Meyer, the first man to conquer Kilimanjaro, returned in 1898, nine years after his ascent, and was horrified by the extent to which the glaciers had shrunk. The ice on Kibo’s slopes had retreated by 100m on all sides, while one of the notches he had used to gain access to the crater in 1889 – and now called the Hans Meyer Notch – was twice as wide, with the ice only half as thick.

Nor are warnings of the complete disappearance of the glaciers anything new: in 1899 Meyer himself predicted that they would be gone within three decades, and the top of Kili would be decorated with nothing but bare rock.
What concerns today’s scientists, however, is that this current reduction in size of Kili’s ice-cap does seem to be more rapid and more extensive than previous shrinkages. But is it really something to worry about, or merely the latest in a series of glacial retreats experienced by Kili over the last few hundred years?

Professor Thompson and his team are attempting to find answers to all these questions. In January and February 2000 they drilled six ice cores through three of Kibo’s glaciers in order to research the history of the mountain’s climate over the centuries. (Follow this link to read a BBC report of their work). A weather station was also placed on the Northern Icefield to see how the current climate affects the build-up or destruction of glaciers.

Although results are still coming in from Professor Thompson’s work, early indications were not good. In a speech made at the annual meeting of the American Association for the Advancement of Science in February 2001, the professor declared that, while he cannot be sure why the ice is melting away so quickly, what is certain is that if the glaciers continue to shrink at current rates, the summit could be completely ice-free by 2015.

Whatever the reasons, if Kilimanjaro is to lose its snowy top, the repercussions would be extremely serious: Kilimanjaro’s glaciers are essential to the survival of the local villages, supplying their drinking water, the water to irrigate their crops and, through hydroelectric production, their power; never mind the blow the loss of the snow-cap would deal to tourism.
And these are just the local consequences. If the scientists are to be believed, what is happening on Kilimanjaro is a microcosm of what could face the entire world in future. Even more worryingly, more and more scientists are now starting to think that this future is probably already upon us.

I have personally witnessed a perceptible change in the position of the glaciers in my annual pilgrimage. That being said, last year was the snowiest trip I have experienced with miles of the mountain blanketed in 6 month old snow and ice. This might lead a first timer to believe that the glacial retreat is a myth. But a closer look reveals that the glaciers themselves are indeed moving. And in glacier years, a noticeable change in eight years is a fraction of a second. I am concerned and would urge all to make a concerted effort to accept Al Gores challenge of disconnecting from fossil fuels by 2018. As with most things satisfying will be extremely challenging, but ultimately rewarding.