RHÔNE GLACIER, Switzerland — On a hotel veranda overlooking Lake Lucerne, Barbara Achrainer sips a latte and, with a sigh, peers at sightseers boarding a tour boat. It's a warm summer afternoon and the hot air over the turquoise water forms a haze that silhouettes the Alps in the distance.
Achrainer has moved from hotel to hotel like this one since late May, when she was forced out of her home. She had just begun a new job as manager of the storied Hotel Fafleralp perched along a mountainside above the village of Blatten. She and her crew were preparing for their first guests of the season when suddenly the workers started running for the exits.
"They yelled, 'We need to leave right now!' And I'm like, 'Why? What, how?' And they literally jumped into their cars and left. And I was like, 'What's going on?'" Achrainer recalls.
Across the valley from the hotel on a peak towering over Blatten, the picturesque Birch Glacier was, unbeknownst to the casual observer, on the move. Scientists noticed it was starting to slide down the mountain faster than it had in decades, on a trajectory so dangerous that they rapidly persuaded the local government to immediately evacuate the village's 300 people.
A week later, as predicted, the glacier broke loose. Video shot by visitor Vitus Brenner shows the glacier crashing down the steep mountainside in a dramatic white cloud of ice, rock and sand. Achrainer was working in the hotel above the valley when the lights flickered and went dark. She went outside and hiked to a nearby cliff to see what had happened.
"It was beyond imagination," she says. "The village is there, but there is no village. It's just basically a pile of mud and sand and rocks. You can't relate to that because this is the place where the village is supposed to be."
Blatten's church, town hall and its homes were buried in an instant.
"An event of that size is certainly nothing I've seen in Switzerland before — not in the recent past," says Daniel Farinotti, a glaciologist at the public university ETH Zurich, which had been observing the Birch Glacier for years.
"The $1 million question is, did Blatten happen because of climate change?" asks Farinotti. "And that's a super difficult question to answer because pinpointing such a causality for a single event, that is very difficult. What we can see is that there were elements in this process chain that may well be related to climate change."
The fastest-warming continent
Farinotti and his team at ETH had observed increased rockfall from the glacier for more than a decade, a phenomenon he suspects was caused by warmer temperatures in the Alps in recent years. Temperatures across Europe are increasing at twice the average global rate. And glaciers in the Swiss Alps have lost nearly two-thirds of their ice over the past century.
Farinotti has been studying these rapid changes for years. According to his team at ETH Zurich, Switzerland's glaciers lost half their volume between 1931 and 2016. But then, in the next six years alone, they lost an additional 12% of their ice.
Wearing crampons, a harness and a backpack full of monitoring equipment, Farinotti leads a team of his students up the pockmarked dirty ice of the Rhone Glacier, the source of the Rhone River, which flows to France. One by one, they carefully leap over crevasses whose icy depths emanate blue light and the echoes of meltwater flowing through a network of cracks and caverns below.
They stop to set up a monitoring station that'll track how quickly this glacier is melting. As his team erects a pole with a GPS receiver and a solar panel, Farinotti peers at the granite mountainsides looming more than 500 feet high on either side of the ice. In 1850 the glacier was flush with those ridges, he says. In the past decade, though, it has melted much faster: Farinotti says the data his team has collected so far shows a stark year-by-year reduction of ice in the Rhone Glacier.
"Where we are standing, we are losing several meters of ice a year," he says. "Maybe 5 or 6 meters in thickness, and in terms of length, it's like dozens of meters a year. That's 2, 3, 4% of the glacier each year."
And at that rate, says Farinotti, "If we stay on track with the climate we have at the moment, then that brings us to a very warm climate. And that would mean that this glacier disappears later this century," he says matter-of-factly. "So by 2100, you wouldn't find any ice anymore."
Farinotti calls glaciers "nature's water towers." The water they've stored for centuries flows down Europe's biggest rivers during the hot and dry summer months, replacing rainwater and snowmelt from the spring.
"If you think of a catchment or an area where you have a glacier and you envisage a very dry, hot summer, well, you will get water because the glaciers are melting," he explains. "If you go to the same area and remove the glacier while in a very dry, hot summer, you don't get a droplet. So the timing at which water will come will change. And this is what the concern is about."
The Rhone isn't the only river whose source is a glacier in the Swiss Alps; the Rhine, the Danube, the Po, the continent's biggest rivers all start here. And when these glaciers are gone, Farinotti says, these rivers will be forever altered.
Preparing for a glacier-less future
Hundreds of miles downstream from the Alps, Steffen Bauer leans over the rail of a tugboat to check the river's depth. Here in Duisburg, a port city on the lower reaches of the Rhine River in western Germany, a massive digital sign reads "250cm" in red neon. "So the normal water level is around 3 meters 50 [centimeters], and now we are 1 meter less compared to the normal situation," he says with a furrowed brow.
Bauer is CEO of HGK Shipping, which builds barges that carry a range of goods up and down the Rhine, the main transportation artery of Germany's economy. He says in recent years, the late summer months have meant record low depth levels on the Rhine. "The low water situation was also in the past, it was always there," he says. "But the problem is that [now] it stands longer, for a longer period we are in this situation. So it's now lasting two, three, up to four months, especially in the late summer, and that's a huge impact."
In the hot, dry summer of 2018, the water level on the Rhine River was so low that barges could no longer navigate the river. That got Bauer thinking about the way Germany builds its barges. "All the barges were heavily constructed to load the maximum capacity. We now need to rethink that," Bauer says.
Since the drought of 2018, Bauer's engineers have been hard at work designing a fleet of low-water barges that can transport up to 600 metric tons of goods in just 1.2 meters — or just over 3 feet — of water. But in an industry that builds just a hundred barges a year, he says it'll take a while to adjust to these new water levels.
Glaciers as climate's poster child
Back on the Rhone Glacier, glaciologist Farinotti's team is preparing to test how quickly water is flowing off the glacier. "First of all we put a salt dilution in the stream there and then we have two measuring points where we measure the salt concentration," explains Michelle Dreifuss, holding a bottle of the solution, "and with that we can examine how much water is coming in a time period."
Dreifuss also adds a visual element to test the water flow — a colored dye. Within seconds of pouring it in, the glacial stream turns bright pink, flowing over a waterfall where the bubblegum-colored cascade disappears into a crevasse. It's a striking visual element for visiting photographers, but for Farinotti, the more shocking visuals can be seen year to year as the glacier recedes before his eyes.
"Glaciers have become a bit of a symbol of climate change just because they are so powerful in visualizing the change," Farinotti says. "When we talk climate change, we are talking about 1 degree of warming of global average temperatures. What does that mean? If you think of heating up your house 1 degree more, I mean, do you feel it? Well, maybe. If you look at what 1 degree of warming does to a glacier, you don't need to be a scientist to figure out, whoa, that's a big change."
It's a big change, he says, that will have a cascade of consequences on rivers, on the ecosystem, and on all of Europe.
Esme Nicholson contributed reporting from Berlin.
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