’Valais is an ideal laboratory to study climate change impacts’

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Jérôme Chappellaz © Jean-Yves Vitoux, Institut polaire français IPEV
Jérôme Chappellaz © Jean-Yves Vitoux, Institut polaire français IPEV
Exploring the climate crisis with Jérôme Chappellaz, environmental scientist and academic director of ALPOLE at EPFL.

Addressing global warming will require politics, industry and academia to develop new, innovative ways of working together, says Jérôme Chappellaz, head of the Ferring Pharmaceuticals Margaretha Kamprad Chair in Environmental Sciences at EPFL. The academic director of EPFL’s Alpine and Polar Environmental Research Centre (ALPOLE) in Sion, regards the canton of Valais as an ideal laboratory to study impacts of and solutions to address our shrinking Alpine glaciers. We spoke with Chappellaz about his concerns and hopes for the future, both in Switzerland and around the world.

Jérome Chappellaz, will there still be ice in Switzerland in 2100?

It depends on how much greenhouse gases we emit into the atmosphere. If we stabilize our emissions and limit warming to the 1.5-degree target set at the COP21 climate conference, then only half of our glaciers will disappear. If we keep emitting 40 billion tons of CO2 per year, many mountain ranges, including the Alps, will be ice-free. From now until 2100 is a micro-slice of history. What we emit into the atmosphere today will remain for a long time. The climate system is relatively sluggish - the glaciers in Greenland and Antarctica haven’t yet caught up with our current atmosphere. These systems are slow and can take decades, centuries, even millennia to respond.

What would be the concrete impact of a snowand ice-free Switzerland?

Most obviously there are anecdotal impacts: We are used to Alpine landscapes covered in snow and ice. It’s hard to imagine our valleys without dominant glaciers. Then there are the practical consequences: our glacial water stores will no longer be available to feed human activities like agriculture in spring and summer.

Couldn’t we simply build more dams?

We could, but we may already have reached a limit in terms of suitable valleys. Remember: the changing climate isn’t just affecting the cryosphere; it’s also changing rainfall patterns. In western Switzerland, we’re likely to see a decrease in summer precipitation, more extreme rainfall events and longer, more intense droughts.

Would you say it’s too late for us to reverse course, then?

2023 could be the first year in which global average temperatures reach 1.5°C above pre-industrial levels. Granted, this would just be a single year, not a multi-year average. But we are talking about a target set for 2100! Our greenhouse gas emissions are not decreasing enough. Even during COVID-19, global CO2 emissions dropped by less than 5% - despite severe economic slowdowns and travel limitations. That should put things into perspective.

That makes it difficult to have an optimistic outlook.

If the earth was the Titanic and the citizens of our planet were the passengers, we scientists would be the lookouts who notice the approaching iceberg. As long as the captains - our governments, and affluent economic players - continue to debate who is the most powerful and what music should play in the ballroom, there’s no reason for us not to hit the iceberg.

I feel like we need to focus on intergenerational responsibility. How will people tomorrow judge their parents’ and grandparents’ actions?

Jérôme Chappellaz

How do we know for sure that humans are to blame for the observed warming?

The science behind the greenhouse effect is well known. The first person to anticipate its existence, in 1824, was Joseph Fourier, the famous French mathematician. In 1861, John Tyndall of Ireland measured the absorption of infrared energy by water vapor and CO2. Then, in 1896, Svante Arrhenius of Sweden calculated surface temperature changes for a doubling of atmospheric CO2 concentration, predicting a 3-degree temperature rise.

That relation still holds true today.

Yes, but that isn’t to say that we know everything. Like, how is the excess heat that stays on Earth transformed, and at what speed? Glaciers in Antarctica and Greenland are losing mass, but we still don’t know just how much and when tipping points might be reached. If the floating glacier tongues rupture, we could see a major increase in sea level. The melting of the Antarctic glaciers at Pine Island and the Twaites "doomsday" glacier could raise the sea level by 15 meters.

What do you say to those that argue that the climate has always been changing?

That misses the point. The question should be: at what speed and magnitude is warming taking place? And what capacity does humanity have to adapt? In this century, the temperature could change by up to 5°C. The last comparable natural major heating event started 20,000 years ago and took 10,000 years to unfold. Back then, we lived in small mobile tribes who could move to better environments. Today, where can we go?

In your expeditions, you’ve seen major transformations at the poles. Can you give us examples?

In Antarctica, the biggest change has been the heat. The French Antarctic station at -67 degrees southern latitude had rain in 2014, 2017 and last year. When it rains on baby penguins, whose fur is not waterproof, they freeze to death. And at the German-French polar station in Svalbard, researchers used to cross the fjord on a skidoo in winter. Today this is no longer possible because the fjord no longer freezes. We’ve seen North Atlantic fish species compete with the Arctic ones. This is impacting indigenous human populations too.


When we feel powerless, we convince ourselves that the problem is not as bad as it sounds. It’s a survival instinct.

Jérôme Chappellaz

What types of solutions are out there?

Reduce greenhouse gas emissions! Geoengineering, for example, might also generate solutions by directly reducing atmospheric CO2 levels. At EPFL, researchers are currently working on solutions at the laboratory scale. But even when there is a scientific breakthrough, it can take decades to scale up solutions for real-world deployment. So far, we have not found a miracle solution.

The evidence is overwhelming, and yet polls suggest that climate skepticism is on the rise. Why?

In my view, it comes back to our natural reflex of denial. When we feel powerless, we convince ourselves that the problem is not as bad as it sounds. It’s a survival instinct. It would be interesting to have social scientists analyze the past four decades since the first IPCC report was published in 1990. This first report stated that it was highly probable humans were causing global warming. Today it’s a certainty. Still, some, including industry groups with major economic influence, continue to argue that the science is not yet settled. This casts doubt on the scientific findings.

What would be a sane way to deal with the situation?

Most people understand the situation but feel powerless. Sure, they could retreat into a cave and live as hermits, but even that wouldn’t make a difference. So, should we pull out the vodka and dance our final dance? Of course not. I feel like we need to focus on intergenerational responsibility. How will people tomorrow judge their parents’ and grandparents’ actions?

You are the academic director of ALPOLE, EPFL’s Alpine and Polar Environmental Research Center. What role do you see the center playing?

ALPOLE’s expertise spans physics, chemistry and biology from high-altitude Alpine phenomena to polar regions. This diversity lets us build bridges between the relevant disciplines. Additionally, with the canton of Valais, we have an ideal experimental playground.

The challenge is to motivate researchers in fundamental sciences to contribute to practical solutions. We need to create a local laboratory of sorts to test ideas with businesses, energy producers and politicians that benefit the local community. The canton of Valais seems motivated to evolve beyond skiing, tourism and wine to spearhead scientific innovation in adapting to the changing climate.

Assuming we succeed in finding a way to manage the challenges that lie ahead, where do you see the seeds of that solution today?

We can see some of it in our universities. Students are making it clear that they don’t just want to be excellent engineers who are good at math and robotics but also seek meaning in their professional lives that rests on planetary challenges. For them, businesses that make millions while negatively impacting water, natural resources and social peace are no longer acceptable. Here, schools like EPFL need to take charge. We’re walking a tightrope. As we train engineers to develop the technologies of the future, we also need to cultivate responsibility in our future scientists. The two are not incompatible.