Icy canaries in the greenhouse
Mountains are crumbling, glaciers are disappearing: the Alps are undergoing rapid change - triggered by rising temperatures. How will the mountains change over the next few years? And what are the main consequences of this for people's lives?
A mountain range is crumbling – at least a little bit: In the last century summer of 2003, more than 1000 cubic meters of rock fell on the Swiss Matterhorn, now on the Eiger more than two million tons of rock are threatening to fall into the valley. Even if these are only two events - albeit very striking in the media - they are still exemplary for the current developments in the Alps.
Europe's central high mountains are already groaning under the consequences of rising temperatures - caused by man-made climate change, almost all scientists agree. The clearest indication that something is happening in the Alps is provided by the region's large and small glaciers: in the last 150 years they have lost more than half their former area, with loss rates increasing significantly in the last decade. As in 2003, the ice giants could again lose five to ten percent of their total volume this summer.
According to new model calculations, the Alps could even be almost completely ice-free by the end of the century. According to Wilfried Haeberli, one of the authors of the study, only giants like the Aletsch Glacier in Switzerland or ice fields beyond the 4000 meter mark could at least partially survive until then - as residual frozen "corpses from days gone by", according to the researcher.
The melting of the glaciers sends out a clearly visible and understandable signal, even for laypeople, that an increasingly rapid change is taking place in the alpine and global environment
(Wilfried Haeberli) For the expert from the University of Zurich, the ice tongues in the greenhouse earth are something like the proverbial canaries as the miners' "alarm system": "The main significance of the glacier melt for science is not only the loss of an important landscape element. Rather, it sends out a clearly visible and understandable signal, even for laypeople, that an increasingly rapid change is taking place in the alpine and global environment." With this demonstration object, present and future generations can clearly see which of the forecast climate scenarios will actually occur.
A long-term risk
But the great thawing has consequences far beyond this illustrative character - and the clearest ones are currently on the east face of the Eiger. Because with the disappearance of the glaciers, their lateral mountain flanks lose their abutment. This leads to relaxation in the rock and pressure relief fissures open up. Meltwater and rainwater are now increasingly penetrating these cracks, which on the one hand can further loosen the rock itself, but on the other hand, when it freezes again, it also develops strong explosive power due to expansion. Such processes take place in the large valley glaciers, some of which still hold the adjacent slopes firmly.
According to Haeberli, this increasing instability will continue to concern the residents and visitors of the Alps long after the last patch of ice has long since disappeared. Changing the stability of mountain flanks is a long-term process. Some rockfalls of the past millennia can still be an indirect result of the great glacier retreat at the end of the last ice age. And on the Eiger, too, it took decades from the disappearance of the Grindelwald glacier to the slippage of parts of its eastern flank today.
For alpinists and mountain hikers, the potential for danger increases in certain regions
(Werner Bätzing) On the other hand, the small glaciers and ice fields on steep slopes cause completely different problems, according to Haeberli: If the ice retreats, it exposes large amounts of debris, which in the event of heavy precipitation - or even just a small shift of a stream bed - suddenly when mudflows can go down into the valley. Just recently, a German tourist fell victim to such a mudslide in the Swiss Corvatsch area. Similar difficulties also arise from the loss of permafrost, which up to now has been a permanent form of freezing that has made rock and rubble areas in the high mountains waterproof and thus increases their stability.
Most of these changes affect the high mountain regions beyond the tree line and therefore pose less of a problem for the permanent settlements in the Alps for Wilfried Haeberli and Werner Bätzing from the University of Erlangen-Nuremberg: "In this respect it works in the majority of cases not about clearing individual areas completely. However, in certain regions frequented by alpinists and mountain hikers, the potential for danger increases," says Bätzing, who has been documenting the cultural-geographical change in the Alps for years.
Trust in technical solutions
The operators of ski lifts, who are feeling the loss of the glacier on their own wallets, are currently directly affected. Last year, for example, the news made headlines that the operators of the ski area on the Gurschen Glacier near Andermatt wanted to protect their source of income from the sun with special films. During the last decade and a half, the glacier surface in the area of the Gemsstock mountain station had dropped by twenty meters, so that the distance had to be bridged with an artificial ramp. Without these access roads, which are expensive to maintain, or the equally expensive tarpaulins, winter tourism on glaciers would no longer be possible in some places – but according to calculations by Haeberli's research group, the supposedly "eternal" ice will probably be over for good from around 2020 or 2030.
Almost ten percent of all cable cars in Switzerland are also built over permafrost: locations that are likely to be increasingly shaky in the future. Experts reckon that the Corvatsch cableways alone will cost ten million francs in additional costs due to damage to the facilities over the next ten years – not counting possible losses in the tourism business. However, the operators trust that these difficulties can be completely managed.
A point of view that the inhabitants of the Alps have now fully adopted, as Werner Bätzing notes: "For about a generation, an 'urban' way of dealing with the dangers of the high mountains has also developed in the Alps, which the Responsibility for the stability of one's own environment - for example one's own valley as a living and economic area - is no longer perceived oneself, but passed on to specialists who are supposed to search for and implement technical solutions. If something does happen, you see this as an insured event or a failure on the part of the politicians."
And since the vast majority of locals would like to stay on site, they call for the problem areas to be technically secured in order to rule out risks as far as possible or at least minimize them - an attitude that the two geographers believe must change again in the future. Purely technical strategies are extremely expensive and yet cannot guarantee 100% safety, as the recent deadly rockfall on the Gotthard motorway showed despite slope structures.
Full speed into the curve?
Science, authorities and the population should therefore work together much more closely and find solutions that are as locally adapted as possible. And a closer look at the mountains is now necessary again, supported by modern technical means such as high-resolution satellite images, precision surveying and computer models.
In this context, Werner Bätzing warns against political groups exploiting the issue of danger as an instrument: "They question the decentralized settlement of the Alps and claim that a decentralized settlement and economic structure in the Alps is in principle too expensive - above all also because of the costly safeguarding of residential areas and transport routes against natural disasters. A pseudo-argument: because one actually wants to concentrate government spending on the metropolitan areas and withdraw funding from the area, but this cannot be said so clearly for political reasons."
Away from these political skirmishes, however, time is already running out to find solutions for the affected Alpine areas, because the speed at which climate change is changing mountain nature is increasing. At the same time, the intervals between catastrophic events are becoming shorter, such as in the case of the two so-called "century" floods that hit Switzerland in 1999 and 2005. The time window for decisions is shrinking, the degrees of freedom for choosing suitable measures are decreasing.
We're approaching a bend at night and in fog, and it would be wise to slow down and turn on the headlights
(Wilfried Haeberli) But not only in Wilfried Haeberli's opinion is there no way around reducing human greenhouse gas emissions: it is the only realistic and effective measure. Adaptation is essential for survival, but slides or ramps are short-term band-aids at best. A fundamental rethink and far-sighted action is urgently needed. Or as the Swiss researcher puts it in an image: "We drive at night and in fog towards a curve that we don't know exactly how tight it is. It would be sensible to slow down and turn on the headlights. Instead, we accelerate and hide the future. This reduces the room for manoeuvre: If you are too fast or the curve is too narrow, you can perhaps only decide whether you want to fly out of the curve with your eyes open or closed."