“Switzerland’s glaciers could vanish completely by 2100”

Daniel, how old were you when you saw a glacier for the first time?
Daniel Farinotti: It must have been in 1987. We went on a family trip to the Rhonegletscher. There’s a photo of my dad, sister and me with the glacier.

Can you remember what kind of impression it made on you?
I don’t have an active memory of this because I was still a small child. But judging by my facial expression in the picture, I was cold [laughing].

Will our grandchildren and their children live to see Switzerland’s glaciers?
It depends whether we manage to cut global greenhouse gas emissions quickly. If we continue as we have done to date, practically all the glaciers in the Swiss Alps will vanish by 2100. On the other hand, if we achieve our goal under the Paris Agreement and stabilise global warming between 1.5°C and 2°C, our grandchildren could still witness at least a quarter of the ice in Switzerland.

What would that mean specifically?
At least the glaciers above roughly 3,300 metre of altitude would still survive. Even part of the Aletschgletscher, with its three majestic ice streams, would still exist, albeit much shorter and thinner. But it’s already too late for many of the smaller glaciers at lower-lying altitudes.

What is the current state of Switzerland’s glaciers?
A sad one. Since the year 2000, glaciers in Switzerland have lost almost 40 percent of their volume, and the loss is accelerating. The last few years have been particularly bad: in 2022 and 2023 alone, 10 percent of Switzerland’s glacial ice was lost due to record-high summer temperatures.

These figures are hard to grasp.
Framing the loss in terms of area may help: since my family photo was taken at the Rhône Glacier in 1987, over 300 km² of glacier area has been lost– that’s almost three and a half times the size of Lake Zurich.

Why are the glaciers melting so rapidly?
The main reason is clearly the changing climate. Since the 1970s, the average temperature in the Swiss Alps has risen by 3°C. As a result, the glaciers are melting more rapidly and drastically during the summer. Changes in winter precipitation only play a secondary role.

What are the consequences of glacial retreat?
The global melting of mountain glaciers and the ice sheets in Greenland and Antarctica are significant contributors to rising sea levels. In a study, we estimated that glacier melt caused up to 21 percent of the sea level rise recorded between 2015 and 2019. Depending on the climate scenario, global sea levels could rise by half a metre to a metre by 2100 – which would be disastrous for people living in coastal regions. And even though Switzerland is landlocked, it could be affected by waves of migration associated with sea level rises.

Does the melting of glaciers also affect the water supply?
Yes, glacier melt leads to a partial loss of regional fresh water resources. Take the water supply in the Indian subcontinent, for example, which is fed not least by glaciers in the Himalayas. If these glaciers shrink, water could become scarce in certain periods and regions.

What does glacial retreat mean for Switzerland?
In terms of water availability, this would definitely affect Switzerland too. In the short term, the melting of glaciers implies an increase in meltwater, but this effect is only temporary as the ice reserves will eventually be used up.

And what then?
In the long term, Switzerland will have less water at its disposal, including for agricultural irrigation and the conservation of ecosystems. As well as the Alpine valleys, this will also affect the major rivers of Central
Europe such as the Rhine, Rhône, Po and Danube, all of which are currently fed by considerable amounts of melt water, especially during dry periods in summer.

What does this mean for hydropower?
We assume that it will still be possible to fill the reservoirs in future. However, the inflow of water will move from high summer to spring and decline in quantity in the long term. The management of these reservoirs will have to take these changes in the water balance into account.

Can we do anything to counteract the retreat of glaciers?
Yes – reduce our greenhouse gas emissions as rapidly as possible. This is the only effective and sustainable way of protecting glaciers. And what’s so great about this approach is that it also reduces a range of other risks, such as heat waves, heavy precipitation, droughts, forest fires, biodiversity loss and so many more.

What about technological interventions? You often see glaciers covered with white fabric.
For the last 20 years or so, the ice of certain glaciers in Switzerland has been covered with white fabric – so called geotextiles. On a localised basis, this method can prevent 50 to 70 percent of melting. However, interventions of this kind are very expensive and cannot be scaled up in size. You cannot save entire glaciers by doing this. Furthermore, the side effects and environmental impact have barely been investigated. Laying out these pieces of fabric is therefore not a “solution” to global glacial retreat.