When the French entrepreneur Jacques Mouflier visited the remote Alpine village of Val d’Isère in 1935, he saw the future before him. “A miracle is going to happen,” Mouflier told his young son, as he gestured towards the mountains encircling the village. “Ski champions from every country will come to compete where we’re standing right now.”

He was right. In 1948 Val d’Isère produced France’s first Olympic ski champion, and ever since, professional athletes have flocked to the village, which sits 1,850 metres above sea level, to train and compete. They are joined by tens of thousands of amateurs. Last year the resort sold 1.3m ski “days” to tourists, and more Britons visit Val d’Isère each year than any other ski resort in the world.

For a long time, the source of Val d’Isère’s enduring attraction – aside from its almost oppressively picturesque surroundings, five-star hotels and 300km of pistes, each one as groomed as a Surrey garden – has been that it is, in the parlance of the skiing industry, “snow certain”. Year in and year out, the arrival of the first snowfall, in mid-November, was as reliable as a Swiss watch. In 1955, when the resort began hosting an annual ski competition called the Critérium de la Première Neige (“the competition of the first snow”), its organisers boasted that Val d’Isère was the only French resort able to guarantee snow throughout December.

Villagers claim to be able to predict the year’s coming snowfall by the berries on the local rowan trees. Plump clumps in summer promise deep snow in winter. For decades, the branches drooped under the berries’ weight. But in the mid-1980s, locals began to notice a change. The date of the first snowfall began to drift later. Patches of bare ground appeared on slopes that, in previous years, had been covered in an uninterrupted white drift. Some ski seasons would have an abundance of snow; others, a scarcity. More consistent was the retreat of the Pissaillas glacier, whose run-off water feeds the surrounding forests; each year it withdrew a little farther up the Pointe du Montet mountain, which dominates the jagged horizon. By 2014, snow was arriving so late to Val d’Isère that, for the first time in its history, the Critérium de la Première Neige was relocated, to a more snow-reliable resort in Sweden.

For reasons scientists don’t fully understand, the Alps are warming faster than the global average. The 1.4C rise in the average global temperature since the end of the 19th century has translated into a 2C rise in the Alps. In the past hundred years, the number of hours that sunshine hits the mountains each year has increased by 20%. The heat and light cause snow to melt, or not to fall at all. In 2017 the Swiss Federal Institute for Snow and Avalanche Research recorded that less snow fell in the Alps during the winter months than in any year since 1874. In April a report by the European Geosciences Union showed that 90% of glacier volume in the Alps – an essential source of drinking water, crop irrigation and ski runs – could be lost by the end of this century.

For the Alpine ski industry, which hosts 35% of the world’s ski resorts across eight countries, and serves an estimated 120 million tourists each year, this is potentially an extinction-level event. Val d’Isère is one of the mountain range’s highest resorts, so it will be one of the last to feel the full effects of the climate catastrophe. But farther down the mountains, the disappearance of snow has already begun to devastate the ski industry, as well as the communities that rely on it.

Since 1960, the average snow season has shortened by 38 days, while “seasonal drift” has pushed the coldest weather from December to the early months of the year, throwing the ski season out of sync with the lucrative Christmas holidays. In November 2017 the EU launched the Prosnow project, whereby scientists advise Alpine resorts on how to “maintain the same season duration with 30% less snow”. Such efforts have not been entirely successful. According to some reports, as many as 200 ski resorts now stand abandoned across the Alps, where bankrupt hotels have been left unoccupied, and forsaken ski lifts dangle in the wind.

The disaster encroaching on Val d’Isère has been obvious to Olivier Simonin, the director of tourism at the resort, since the infamous 2006-7 season, when a scarcity of snow caused a 7% decline in revenues across Alpine resorts. This September, for the first time, the French ski industry’s main union, Domaines Skiables de France, held an emergency meeting of directors from France’s most important resorts to discuss the existential challenges they face. Twenty-five directors attended the meeting, which was held in the valley of Chambéry. The mood, according to Simonin, was sombre. “This is now the main topic of conversation among us,” said Simonin. “Nobody wants to die.”

Unlike the islanders of Kiribati, whose homes will be swallowed by the Pacific Ocean in the coming years, or the farmers of rural Bangladesh, whose crops fail whenever their fields are flooded by saltwater, the Alpine ski industry, which turns over billions of euros every year, is disproportionately well-equipped to fight for its survival. And resorts like Val d’Isère have invested tens of millions of euros in the most straightforward solution imaginable: when the snow stops falling, it’s time to make your own.

“You need four things to make snow,” Pierre Mattis told me in September as we toured the control centre of the snow-making operation he runs in Val d’Isère. “Water, air, cold and talent.” One morning in 1995, Mattis, who was then a 28-year-old ski-lift engineer, was told he was being redeployed to look after the resort’s handful of snow machines. Four years later, he began building his snow-making factory, or atelier neige, installing a 70km network of pipes beneath the mountain that now, after years of expansion and improvement, can cover 65 sq km of slopes in artificial snow at the touch of a button. It is one of the most sophisticated snow-making operations in the world.

The first snow-making machines in Europe appeared in Italy in the early 1980s, just before the locals in Val d’Isère began to notice the seasons shifting. (In 1963 snow-making equipment was installed at Mar Lodge in Scotland, but the project was abandoned after two seasons as the water kept freezing.) As winters with unreliable snow became more common in the Alps, so did the machines. Most were based on a design by a Pennsylvanian man named Herman K Dupré, who in 1968 had fitted a water sprinkler to an air compressor system he bought at a scrapyard. Dupré pumped the air and water at high pressure through a lance-like nozzle to create a fine spray that, at sufficiently low temperatures, turned to snow before it hit the ground. The HKD snowmaking system, as Dupré named his invention, became the industry standard. The first one arrived in Val d’Isère not long before the snow-scarce winter of 1986.

Warm winters had occurred before the mid-1980s, Robert Steiger, an economist and tourism researcher at the University of Innsbruck, told me, “but at that time Alpine communities had not been so dependent on ski tourism.” Today, 95% of Italian, 70% of Austrian, 65% of French and half of Swiss ski resorts are reliant on snow machines for their continued survival, according to estimates from Claus Dangel, CEO of Bächler, a snow-machine maker that supplies more than 200 resorts across the Alps.

It takes an awful lot of technology, water and energy to manufacture the amount of snow that might have naturally blanketed the Alps two or three generations ago. Mattis’s control centre in Val d’Isère is housed in a cavern chiselled into the mountainside, like the bunker of a Bond villain. It is large enough to house some 40 double-decker buses, and home to six 10ft tall pumps, water filters, and a phalanx of computer screens – all maintained by Mattis’s 12-member “snow team”.

Snow cannon in the Swiss Alps. Photograph: Simon Parkin

Using software developed in-house, the team controls a vast network of snow machines via a bank of 10 computers. Like the timer on a boiler, the software allows the team to set “on” and “off” periods for the snow machines, ensuring a consistent covering of snow throughout the season. Forecasts fed into the bunker from weather stations on the mountains help the team to adjust their schedules. During the ski season, three people monitor the system throughout the night, like security guards watching over a bank vault. They check the correct positions of the cannons in relation to the prevailing wind, watch the quality of snow, and ensure that the pump rooms are working satisfactorily. If a patch of ground appears in the melting snow, they can cover it before sunrise.

The snow is shot on to the mountains at a speed of 250km/h via 650 snow cannons. Ten years ago the cannons could be spaced 80 metres apart from one another and still create an unbroken blanket of snow, but climate change has since forced Mattis to cut that distance in half. The system has to be continually upgraded to keep pace with the effects of climate change. The current iteration was completed in 2014 at a cost of €2m, and can produce 8,000 cubic metres of snow per hour – eight times the capacity of five years ago. The plant is one of the largest in the Alps, and differs from most of its rivals in that all of the equipment (bar HKD’s nozzles, which are imported from Quebec) was designed in-house. Mattis claims his system is unique as it allows the team to control the density of the snow on a sliding 10-point scale, enabling him to create a more compact, “faster” snow, ideal for professional competitions.

This technology comes at a major financial and ecological cost. Today, one in every 20 euros spent anywhere in Val d’Isère goes into the snow factory, covering energy costs, staffing, maintenance and upgrades (a hidden “artificial snow” tax that is continually increasing). Although snow machines are becoming increasingly efficient, a typical snowmaker still uses about the same amount of energy as a boiler in a family home. When multiplied into the tens of thousands across the Alps, snowmakers become something of a self-defeating invention: they worsen and sustain the climate problems they’re supposed to solve.

And yet, for life in the Alps as we’ve come to know it, they remain essential. Steiger’s most recent simulations suggest that unless every ski resort in the Alps installs state-of-the-art snowmaking facilities like the ones Mattis operates at Val d’Isère, by the 2050s up to half will no longer be able to sustain their businesses. Only the wealthiest resorts, like Val d’Isère – where chalets can sell for more than €23,000 per sq metre, five times the average cost of property in London’s most expensive borough, Kensington and Chelsea – are able to make the necessary investments to continually update and retool their snow-making facilities.

Less-moneyed resorts rely on a cheaper source – snow farming, whereby snow is gathered or made in January and February, when manufacturing snow costs less than in warmer months. The snow is then placed under a 40cm layer of wood chippings, which absorb and release moisture and keep the snow cool, compact and manageable during the summer months. The wood chippings are then removed at the end of October, allowing the snow to be deployed on the slopes in time for the skiing season.

Artificial snow, be it farmed or sprayed, is not only the would-be saviour of the ski industry, however. This is a region where, as the International Commission for the Protection of the Alps, Cipra, puts it, “there is an urgent need for innovative ideas and solutions”. One Dutch professor believes artificial snow may also hold the key to saving glaciers, in the Alps and beyond – along with the communities that rely on them for their food and water.

On the morning of 11 July 2000, after a night of unexpectedly heavy summer snow, Hans Oerlemans went to check his weather station on the Morteratsch glacier, near the village of Pontresina, Switzerland, 400km north-east of Val d’Isère. The Morteratsch is one of the largest glaciers in the Alps, and a popular attraction for sightseers and thrill-seekers, many of whom come to ski along its 6km back. Since 1860, though, the glacier has shrunk by 2.5km – an average of nearly 16 metres per year.

Oerlemans believes lessons learned by studying the Morteratsch can aid anyone interested in saving snow and ice across the Alps. A Dutchman who grew up in Utrecht, Oerlemans is tall and handsome, and wears the thin-rimmed glasses of a Hollywood therapist (studiously removing them for photographs). He has been studying glaciers since 1980, when he earned his PhD from Utrecht University, where he is an emeritus professor. His weather station on the Morteratsch, which he personally built in 1995, was one of the first in the world designed to measure the effects of climate change on glaciers. By monitoring the Morteratsch’s vital signs – fluctuations in the depth and temperature of its ice, as well as the ambient humidity – he hoped to solve a number of basic, yet unanswered, questions. “If the climate becomes one degree warmer,” he told me recently, “what happens close to the surface of a glacier: do you have 1 metre more of ice melt, or 10cm, or 10 metres? Nobody knew.”

Hans Oerlemans in the Swiss Alps. Photograph: Simon Parkin

When Oerlemans crested the mountain that overlooks the Morteratsch that July morning two decades ago, he expected to see the glacier in its state of typical summer resplendence – a great frozen river, flowing in imperceptible slow-mo down the mountain. Instead, he saw nothing but snow, covering the glacier in a half-metre-deep drift. In the weeks that followed, he noticed something even more surprising in the weather station readings: the glacier’s thaw had halted almost entirely.

Two processes melt ice: the transfer of heat from warm air, and solar radiation from the sun. Oerlemans’s readings suggested that the latter had a much greater effect than scientists previously understood. The covering of snow from the unseasonable summer storm had apparently acted as a reflective shield, fending off enough solar radiation that it was equivalent to dropping the air temperature by a full degree. He wrote up his findings in a paper published in 2004 by the International Glaciological Society. Then, for a while, he put what happened to the back of his mind.

This autumn, as Oerlemans and I took a bobbing cable car up to a viewing station overlooking the glacier and mountain-top restaurant – home to “probably the most expensive plate of spaghetti in Europe,” he said – he explained what happened next. About five years after his paper was published, the villagers in Pontresina learned about an experiment in which polyester fleece has been used to cover snow to preserve it during warm weather. They laid the fleece on to the glacier in two-metre wide strips, like a blanket shorn from a massive sheep. “They put it out in the middle of May, and covered the ice till September,” he said. Not only did the fleece blanket stall the effects of melting, it actually reversed them: measurements showed that, over the course of the summer, ice in some of the areas under the fleece grew in thickness by up to two metres.

When news of this ice reversal reached Oerlemans, he immediately thought of the weather station reports following the heavy snow drift in July 2000. If it were possible to cover a glacier in a protective barrier during the spring and summer months, might this counteract a century of decline? “The scale is totally different,” Oerlemans recalled. “You could not use fleece on a glacier the size of the Morteratsch, which moves, because it will be destroyed quickly. But, I thought: it might just be possible to use artificial snow.”

Oerlemans at the Morteratsch glacier. Photograph: Simon Parkin

To test the theory, in the summer of 2017 Oerlemans and his team sprayed a 2.5 metre-deep blanket of artificial snow over a small section of the Diavolezzafirn glacier, one of the Morteratsch’s diminutive neighbours. The experiment, which ran to the autumn, was successful: further melting was prevented, and in some places the ice even grew.

With positive results in hand, Oerlemans and his collaborators began to consider the much greater challenge of how to blast a sufficient amount of artificial snow over the much larger expanse of the Morteratsch. Snow cannons such as those installed in Val d’Isère could not be placed on to the glacier, as they would be caught in the slow-moving current of the ice and torn from their pipes.

Instead, Oerlemans and his colleague Felix Keller considered using a cable car equipped with a snow machine to travel above the glacier, dropping artificial snow as it went. (Oerlemans and Keller’s partnership is not short on creative thinking – the pair also play in a two-piece tango band called Tango Glaciar and often splice musical performances into their lectures on glacial retreat; once they even performed on a glacier, which one onlooker drolly likened to the musicians on the Titanic stubbornly playing while the ship sank.) This idea stalled when it came to supplying a moving cable car with the necessary water to make the snow. Finally, in a eureka moment, the team settled on an ingenious invention: a “snow rope”, stretched in a zigzag pattern across the width of the glacier, hundreds of feet across. Acting like a sprinkler system, the rope could deposit snow from altitude while the glacier trundled conveyor belt-like beneath it.

After two years of preparatory studies, finding willing engineering partners and filing patents, on 1 October 2019 Oerleman received a 2m Swiss franc grant from the Swiss Innovation Agency to begin work on his extravagant snow blanket scheme. “We have passed the point of no return,” Oerlemans told me. “It’s no longer just theory; it’s happening.”

On a warm morning this past summer, I hiked with Hans Oerlemans along a dirt path from the village of Pontresina up to the Morteratsch glacier. Perhaps to convince sceptical visitors of the scale of the Morteratsch’s retreat, the village council had erected 2.5 metre-tall markers along the path to show how far downhill the tip of the glacier stretched in certain years. With an accumulating sense of dread, we walked from the marker for 1865, which sits close to a car park at the base of the mountain, and past the ones for 1940, 1960, 1980. The farther we walked, the farther away the next marker was – the glacier’s retreat was accelerating over the decades. The effect was like trekking along a countdown to the oblivion of the glacier, or perhaps even our own.

Along the steep-sided valley carved out by the glacier over millennia, the cliff walls most recently vacated by the shrinking floe are packed with “dead ice”, a dark grey substance that looks like granite. Dead ice poses a major threat to sightseers because it can cause massive rock falls; last summer a boy ignored a set of warning signs and wandered less than 50 metres from the main tourist path. He was crushed to death by a falling boulder.

Pontresina, in the Swiss Alps. Photograph: Simon Parkin

The villagers of Pontresina are distressed by the likely effects of the erosion of the ice on the village’s tourist economy, Oerlemans told me. But not everyone is convinced that his snow-blanket scheme is the best use of 2m francs. “I am sceptical of the entire project,” an employee from the local council said. “It’s such a huge amount of money, and it’s not clear what effect it will have.” Even if the scheme meets expectations, there is a sense that the funding behind the glacier-saving technology has essentially been awarded to prop up the skiing industry, the recreational embodiment of extreme privilege – just like the artificial snow operation in Val d’Isère.

Oerlemans and his team argue, however, that if the wealthy ski resorts of the Alps can facilitate the development of these technologies, they will have a knock-on effect in the coming years, enabling poorer communities around the world to benefit from these advances. The professors’ snow rope system may provide a solution, ensuring the survival, not only of expensive tourist resorts, but also farming communities, such as those in India and Tibet, whose crops are reliant on glacial water. “There are 230,000 glaciers in the world, and it’s unthinkable that you could use our technique on a scale that would, for instance, stop glaciers from contributing to sea-level rise,” says Oerlemans. “But at a local level it could prove invaluable for local economies that depend on melt water from glaciers for their survival.”

That technologies developed for the rich will one day help the poor is a familiar refrain among tech idealists – and a dubious one. “Assuming that western technologies can be easily implemented in developing countries is a bit naive,” said Robert Steiger, from the University of Innsbruck. “Poor regions in poor countries lack the institutional background that is required to implement new technologies and, even more importantly, to provide the knowledge and money to maintain this technology.” Besides, Claus Dangel, the CEO of the snow machine company Bächler, which is currently developing Oerlemans’ snow sprinkler, estimates that the company needs an additional 3.5m Swiss francs to fully develop the system – far more investment than is provided by the Swiss Innovation Agency grant.

Dangel’s hope is to make the system as low-energy as possible, perhaps by using gravity to feed the sprinkler system from lakes high in the mountains, above the snow rope. “We want it to work without using energy,” he told me. “But this is very complicated because you need high water pressure, and the system will probably need to be heated in one way or another, to prevent it from freezing.”

In the long term, it seems unlikely that artificial snow will save even the wealthy Alpine ski industry. Resorts are beginning to consider how they might make more fundamental changes to their businesses in order to adapt to, rather than stave off, the effects of the climate crisis. For many resorts, this means reorienting themselves around non-skiing activities: hiking, mountain bike-riding, nature-watching, sightseeing. “We can see what is coming for us,” said Olivier Simonin, the director of the resort at Val d’Isère. “There will need to be a complete change.”

By 2050 Simonin hopes that 30% of the resort’s income will be derived from activities other than skiing. The number of tourists visiting the Alps during the summer is already increasing year on year, according to the World Wide Fund for Nature. Changes in climate are being matched by changes in what visitors, especially millennials, are looking for. But hiking and other summer activities are less profitable than skiing, so although tourism may endure, the stratospheric revenues of the heavy snow decades may not. “We may have a bit more time compared to others but, then again, we are a big resort,” Simonin said of Val d’Isère. “We have a greater economic challenge in order to maintain our current levels of profit.”

For a few moments Simonin held his head in his hands. “It will require solidarity between the villagers, the resorts, the hotels,” he said, finally. “But people who live in the mountains are hardy. We are used to having to adapt.” Perhaps, he wondered, with a note of surprise at what appeared to be a fresh afterthought, whether in 50 years, people might come to Val d’Isère, not to ski but simply to see snow – human-made or otherwise – precisely because of its scarcity. With a dry laugh, he added, “Maybe the mere sight of snow will become a privilege.”

• This article was amended on 20 December 2019. Owing to a unit conversion error, an earlier version stated that property prices in Val d’Isère were 20 times higher than in Kensington in London. It has been corrected to five times. A reference to an early snow-making programme in Scotland has also been added.

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