The Greater Aletsch Glacier, a journey into the melting heart of the Alps

In the heart of Switzerland lies the largest glacier in the Alps, the Greater Aletsch Glacier. However, climate change is threatening its very existence.

In 1674, residents of Fiesch, a village in the Swiss canton of Valais at the feet of the Greater Aletsch Glacier – the largest in the European Alps – established a Catholic ritual to ask the heavens to stop this and the nearby Fiescher Glacier from advancing, and therefore threatening their safety. The pilgrimage has been held every year on the last day of July for the past 340 or so summers.

After reaching its peak extension in the mid-1800s, the Aletsch Glacier began receding and has continued to do so at an accelerating pace. In 2009, in recognition of this new turn of events, the local parish petitioned the Vatican to alter the ritual to ask for the glaciers to stop melting instead. “Glacier is ice, ice is water, water is life,” the new prayer, approved by the highest Catholic authority, invokes.

A decade later, in September 2019, a funeral ceremony was held to mark the disappearance – or death – of the Pizol Glacier in Switzerland’s Glarus Alps, about a hundred kilometres northeast of Fiesch. Hundreds of people came together to commemorate what was left of the ice body, one of the first to be excluded from annual measurements of Swiss glaciers. 

Performing rituals, ceremonies and spiritual pleas are just some of the ways that communities are trying to cope with the seemingly relentless loss of Alpine glaciers. These landscapes aren’t only key to the well-being of the environment but shape the way of life and culture of entire societies. Their vulnerability to the onslaught of anthropogenic climate change is increasingly evident as glacier loss accelerates in relation to the rise in global temperatures. A process whose social, environmental and even emotional consequences are huge, and a vivid visual manifestation of the stress our planet is enduring. 

Aletsch Glacier
Aerial view of the Greater Aletsch Glacier as seen from the Konkordiahütte September 2019 © Kevin Kok

“Glaciers show very clearly how the climate is changing,” explains Matthias Huss, a glaciologist at ETH Zurich and head of Glacier Monitoring Switzerland (GLAMOS). “They’re much better in visualising what climate change does than just a temperature graph, for example”. As we struggle to come to terms with the ongoing climate crisis, the stark reality of glacier loss is a canary in the coal mine warning us of the irreversible consequences of global warming.

The Greater Aletsch Glacier

In the heart of the European Alps, these facts are particularly glaring. Konkordiaplatz, or Concordia Place, is the convergence point of four glaciers concordia is the Latin word for harmony and union, literally “with (one) heart” – which join at 2,700 metres above sea level to become the Greater Aletsch Glacier. This vast expanse of ice, part of a Unesco World Heritage Site, is over 20 kilometres long, up to 800 metres deep and around 80 square kilometres large. It contains over a fifth of the total ice volume in the Swiss Alps and is by far the largest glacier in the European Alps.

Yet it has already retreated by over 3 kilometres since 1870 and is expected to lose at least half of its volume by 2100 according to the most optimistic projections. In worst-case climate scenarios – in which greenhouse gas emissions continue unabated – it could virtually disappear by the end of the century

With the retreat of the Aletsch, we risk losing the heart of one of the world’s most iconic mountain ranges.

The melting heart of the European Alps

Iconic among the features of the Aletsch Glacier is its long, meandering ice tongue. Framed by five 4,000-metre peaks, it stretches out from the Konkordiaplatz for 14 kilometres. 

Having already receded by about a kilometre since 2000, the tongue is expected to retreat by a further twelve by the end of the century according to the most optimistic predictions, in which the meteorological conditions of the last decade remain stable. Even in this scenario, most of the mighty mass of pearly white and frosty blue ice could be reduced to piles of morainic debris.

These are just some of the sobering conclusions presented in a 2019 study published in the Journal of Glaciology by Huss and Guillaume Jouvet, a senior researcher at the University of Zurich, which looks at the impact of different climate scenarios on the Aletsch Glacier by the end of this century.

Aletschgletscher, Aletsch Glacier
Aerial view of the Konkordiaplatz, Greater Aletsch Glacier 1949 © E-Pics Bildarchiv / Wikimedia Commons

“A significant ice body, with glaciers still coalescing at Konkordiaplatz, will resist climate change until 2100,” in the case of a moderate emissions scenario, in which ambitious mitigation efforts to keep global temperature rises within 2 degrees compared to pre-industrial levels, as set out by the Paris Agreement, are pursued. Yet the Aletsch could still lose 57 per cent of its volume, 31 per cent of its surface area and 56 per cent of its length compared to 2017.

The glacier is predicted to lose a median of three quarters of its ice volume if, instead, we fail to hit the Paris target and temperatures increase by 2 to 4 degrees relative to 1960-1990. The emblematic glacial tongue – which continues to mesmerize visitors who flock to this unique area – would be completely disintegrated, with ice bodies found only above 3,000 metres above sea level.

Practically none of the glacier would be left if emissions continue to rise without control, leading the planet to heat by 4 to 8 degrees. Even the Konkordiaplatz, where the glacier is currently up to 800 metres thick, would become ice-free.

Our results confirm that a substantial wastage in ice volume and length of Great Aletsch Glacier has to be expected by the end of the 21st century, regardless of the considered climate scenario.

Jouvet and Huss, Journal of Glaciology 2019

The consequences of global warming are already well underway here, in the heart of the Alps, and putting a break on glacial retreat is anything but simple. Even if the international community were to succeed in coalescing around serious, concrete climate action and stop emissions from rising, the Aletsch Glacier would continue to retreat.

Whereas smaller glaciers can respond rapidly to changes, for better and for worse, large glacial masses such as this one have a long response time to climatic factors.

“Voluminous glaciers … are valuable indicators of long-term climate trends, since they’re almost insensitive to short-term swings, such as those that caused many small glaciers in the Alps to advance in the 1920s and 1980s,” write Jouvet, Huss and other researchers in a 2011 study.

The effects of global warming in the Alps

The trend seen in the Aletsch region is a microcosm of what is happening to all of the Alps’ glaciers. “By 2050, those below 3,500 metres above sea level will lose their accumulation area and, hence, are condemned to disappear,” explains Michael Zemp, professor at the University of Zurich and Director of the World Glacier Monitoring Service (WGMS). More than half the ice volume is expected to disappear by mid-century even if CO2 emissions were to stabilise and regardless of our actions to tackle the climate crisis.

Since 1850, the volume of ice in the Alps has halved, with 17 per cent of the decline occurring since the turn of the new millenium. As temperatures have increased in recent decades – with the past six years being the hottest since records began – changing weather patterns and summer heat waves have left an indelible mark.

Since 1960, Swiss glaciers alone have lost enough water to fill the whole of Lake Constance, with significant repercussions such as the disappearance of the Pizol Glacier, the collapse of the Turtmann Glacier in Valais in August 2020 and the emptying of the glacial lake on Plaine Morte. The past decade has been the worst for glacial retreat in the Alps since observations began, with almost 2 per cent of Switzerland’s total glacier volume having melted over the course of 2020 alone.

“Alpine glaciers are expected to shrink even more quickly over the coming decades,” Huss points out. Huss and researchers Harry Zekollari and Daniel Farinotti have applied climate simulations to investigate what lies ahead in terms of glacier loss. 

Under a conservative scenario, which forecasts a rapid stabilisation of atmospheric CO2 levels up to the end of the century, the European Alps are expected to lose two thirds of present-day glacier volume and area. When considering the most pessimistic warming scenarios, the 2019 study indicates that these mountains could be largely ice-free by 2100.

“Although we will still lose many parts of big glaciers due to the current imbalance with the present climate, we can save at least some parts of glaciers if we stay below 2 degrees warming,” Zemp explains.

While scientists’ projections offer a bleak image of the future, they simultaneously present a window of hope: the decisions we take today regarding our emissions pathways can have a significant impact which can be measured objectively in terms of how much of glaciers we’re able to save. 

Something worth fighting for

“Every day, I have something to do with the Aletsch,” says Laudo Albrecht, Director of the Pro Natura Center Aletsch in Riederalp, which has been dedicated to nature conservation in the Aletsch Arena since its founding in 1976. “In the thirty years (since working here), the glacier has become like a friend to me. But this friend is now disappearing”. Glacier decline is a source of emotional distress for Albrecht and those who, like him, are starkly aware of its environmental and social consequences.

Matthias Huss
Matthias Huss measuring ice levels on the Findel glacier in Switzerland © Matthias Huss

As well as contributing to rising sea levels, melting glaciers pose a direct threat to mountain communities especially in the warmest months of the year. In August 2020, the inhabitants of the Ferret Valley in the Italian town of Courmayeur were evacuated due to the potential collapse of Mont Blanc’s Planpincieux Glacier. While the crumbling of 500,000 cubic metres of ice – equivalent to 200 Olympic swimming pools – was averted, these events warn of the risks Alpine communities are increasingly facing.

Glaciers are also key components of the water cycle, acting as sources of freshwater that are replenished and stored in the winter and flow towards the valleys below in the warmer months. The Aletsch’s meltwaters, for instance, feed the Massa River, a tributary of the Rhône River in Switzerland and France, one of Europe’s most important waterways. 

Their economic value, too, is immense, for example as sources of hydroelectric energy and given their importance for the tourism sector. Albrecht knows this well. He accompanies visitors on the Aletsch Glacier to experience its grandeur first hand, which he believes is an excellent way to bring people closer to his friend. 

Upon feeling the awe that this landscape naturally inspires, and with a better understanding of the threats it faces, people are more likely to become invested in the glacier’s future. To get people to care about the fate of our natural heritage, “we shouldn’t begin by talking about climate change,” which can feel abstract, but rather “we should begin with the glacier,” Albrecht believes.

The September 2019 ceremony to commemorate the Pizol Glacier was held with this same spirit. Bringing people physically close to what little was left of the ice mass was a way “to show them what is happening to all mountains,” says Alessandra Degiacomi, head of external relations of the Glacier Initiative, which organised the event. “It’s not just about this glacier, it’s about all glaciers. It’s about all our climate. It’s about our planet,” Huss adds. 

“This was an opportunity to act: walking all the way (to the Pizol), feeling part of a community and seeing up close what we’re fighting for,” in the words of one of the ceremony’s participants, Savannah Goetsch, a biology student at the University of Zurich. 

Climate change is close to my heart because of what we risk losing.

Savannah Goetsch

Far from Alpine glaciers’ ice formations and morainic fields, the Glacier Initiative launched by the Swiss Association for Climate Protection is bringing the issue of glacier loss and its underlying causes to the heart of Swiss politics. In five months after its founding in 2018, the organisation collected around 113,000 signatures in support of a homonymous federal popular initiative – 13,000 more than those required to activate this mechanism, which allows citizens to propose changes to the Constitution.

Proponents of the “glacier initiative” want the goals of the Paris Agreement to be enshrined into Swiss law – therefore obliging national and local governments to abide by them – and that a strategy to reach net carbon neutrality by 2050 (at the latest) be set out. A popular vote on the initiative could be called between 2022 and 2024 depending on the outcome of the consultation process, which began when the popular initiative was officially accepted a little over a year ago.

What lies downstream

It is no coincidence that the Swiss popular initiative demanding concrete action on the climate crisis is named after glaciers. For a country whose culture, society and economy are inseparable from mountain landscapes, these environments represent the most dramatic and concrete symbol of what we stand to lose.

Huss, Zemp, Albrecht, Degiacomi, Goetsch and all their fellow citizens are on the frontline of a struggle that concerns us all. As those closest to the Aletsch and other glaciers, they’re in the privileged position to act as sentinels of the ways in which these landscapes are changing. Yet it is everyone’s responsibility to listen to the facts they present and the pleas they make because glaciers benefit us all and are under all of our watches.

Although these environments key to life on Earth as we know it will inevitably continue to shrink, the extent of this loss is something that still remains within our control, as reducing emissions and limiting global warming will determine their fate. What we do today can shape the future of Alpine glaciers and stop them from losing their beating heart.

Related articles