How to Make Snow for a Winter Olympics in a Dry City
Wang Feiteng has spent much of his career keeping an eye on China’s glaciers, making arduous treks into the mountains every year to study how to slow their decline in a warming world.
More recently, however, his work has involved a different kind of ice formation. Wang and his team are in charge of the artificial snow needed for the 2022 Beijing Winter Olympics, set to start on Feb. 4.
Beijing and the mountains to its north — where some of the events, including skiing and snowboarding, will be held — are notoriously arid and see very little snowfall in winter. Moreover, temperatures in February could rise below freezing, and there’s a risk of storms that will dust the top layer of snow in sand. As a result, the Beijing games will rely entirely on artificial snow.
As global snow coverage declines due to climate change, more winter sports events are adopting artificial snow. During the 2010 Winter Olympics, host city Vancouver experienced an unusually warm winter that forced organizers to bring in artificial snow. The Games in Russia’s Sochi and South Korea’s Pyeongchang also could not rely on natural snow.
A recent study, which assumed current global greenhouse gas emissions, concluded that only one of the previous 21 Winter Olympics host cities would have the right climate condition to host the games again by the end of the century.
China does not have a rich history in winter sports. They have only recently become popular among the wider public, picking up only after Beijing won its bid to host the 2022 Games, in 2015, and pledged to “motivate 300 million people to become involved in ice and snow sports.”
Two years later, in 2017, an expert team of the International Ski Federation — the organization responsible for several major Olympic skiing and snowboarding competitions — toured several ski resorts in China and found they didn’t have any pistes that met their standards.
Better artificial snow was needed for the Olympics. Wang, 32, is a glacier researcher at the Chinese Academy of Sciences and one of a handful of people in China who study how snow changes over time after it falls to the ground. He has spent years observing snow on glaciers and researching how to best preserve snow to slow down glacier melt. But prior to joining the Olympics snow service team in 2016, Wang didn’t know much about making artificial snow — as did barely anyone else in China.
The Olympic snow service team has spent the past four years racing to figure out how to make snow good enough for world-class sporting events that will be held in climate conditions unlike others. Different competitions require various snow textures, and it took the team several winters, numerous experiments in frigid weather, and a trip to Pyeongchang to work out the recipes for the best artificial snow.
Since last November, Wang and his team had been loading cannon-like snowmaking machines with water. These cannons shoot out ice crystals and water droplets, which combine to form snow when it lands on the ground. Mounds of human-made flakes are now piled up near the venues that will host races such as big air, ski jumping, and alpine skiing. Over 70 gold medals will be handed out for games on snow during the 2022 Winter Olympics.
Wang’s work now consists mostly of meticulously checking on the snow piles, measuring their grain size, temperature, and density to make sure they are optimal for the Games ahead.
Speaking with Sixth Tone over the phone from Beijing, Wang discusses the technology involved in making snow for the Games, how climate change poses a challenge, and how his Olympic job compares to his usual research. The interview has been edited for brevity and clarity.
Sixth Tone: What do you need to make artificial snow?
Wang Feiteng: All that’s needed is water, which is put through the snow cannons where the water combines with air to make snow. But different games require different snow densities.
For games like cross country skiing and Nordic combined, we want snow that’s the most similar to fresh, natural snow, which has a density of around 200 kilograms per cubic meter. For big air events, we want less powdery snow with a density of around 400 to 500 kilograms per cubic meter.
Snow for alpine skiing events, including downhill and slalom, is the most difficult because its density has to reach 650 kilograms per cubic meter. We call this type “icy snow,” for it is almost as hard as ice so skiers can race at their top speed, but needs to remain snow so skis and snowboards can still carve into it.
To make icy snow, we use pumps to inject water into the artificial snow on the ground to produce snow grains of the right size to reach the desired snow slope density. The process is harder than it sounds because multiple environmental factors such as temperature and wind can affect the snow quality. We spent years running tests to figure out the optimal combination of parameters for the weather in Beijing, like water pressure and injection time.
Sixth Tone: Is all the snow for the Games already made?
Wang Feiteng: Yes. The games are about to start, so we had all the snow made last November and December, during the coldest time of the year.
One reason is that snowmaking cannons work the most efficiently when the temperature is below -10 degrees Celsius. More snow could be produced with the same amount of water compared to slightly warmer weather. Beijing is beginning to warm up, so running the cannons now would be more resource-intensive.
All the snow is stored outside in empty spaces near the venues and covered with large reflective pieces of cloth, so sunlight doesn’t melt the snow.
The snow density changes as the snow is piled up because of factors like changes in temperature and gravity. We have taken that into consideration when we make the snow. For example, if we’re making snow to be used in two months, we will make snow that’s lighter, which will become denser as it sits in a pile. I have studied how snow on glaciers changes over time for years, so this is where my expertise comes in.
Sixth Tone: Does Beijing’s climate pose a challenge to maintaining snow quality for the Games?
Wang Feiteng: We have designed contingency plans for different weather events like snow, rain, and sandstorms. If any of that happens, it will change the snow condition on the slopes’ surface. We will need to scrape the top layer of snow off and replace it with a new layer of stored snow.
Fresh, natural snow isn’t actually good for the competitions except for events like cross-country skiing that use a more natural snow track. For high-speed alpine skiing, the fluffy natural snow is actually dangerous. Because of the differences in density, the natural snow layer would have low friction against the icy snow layer underneath, increasing the risk of an avalanche.
Sixth Tone: Does climate change bring challenges to snow service?
Wang Feiteng: Certainly. For one, a warming climate means there’s less time for snowmaking cannons to work efficiently. The majority of ski resorts in the world use artificial snow, so the impact is significant. Ski resorts would also have to shorten their open season, because snow melts quickly. It’s not great when we want to encourage more people to participate in these winter sports.
Sixth Tone: Is making snow for the Winter Olympics difficult work?
Wang Feiteng: It isn’t compared with glacier research. Even though we have to conduct experiments outdoors in winter, we usually work at ski resorts, which are very close to cities and have modern amenities.
When I go on expedition trips to glaciers in China’s northwest in the summer, which is also frigid cold, we go to regions that are usually uninhabited and undeveloped. Most of the time, we have to hike on ice for hours, sleep in tents, and spend days without a phone signal.
So, compared to that, working on snow service for the Winter Olympics is not very hard work.
Sixth Tone: What makes you proud?
Wang Feiteng: To be honest, before I’m tasked with snow-making for the Games, I simply assumed there would be no obstacles in hosting the Winter Olympics, especially considering our country’s economic strength. But after I started working in this area, I realized China had barely any experience, no talent, and no technology to provide snow service for the Games. We have institutions for training professional skiers and snowboarders, but no one researched snowmaking scientifically.
We had to start from scratch. But now, I’m proud to say that we are the first team in China to study snowmaking, including snow storage, for sporting events. We published the first scientific papers in this area in China and trained the first group of graduates to do research in the field.
Editor: Kevin Schoenmakers.
(Header image: A Winter Olympic staff inspects tracks at a sporting site in Zhangjiakou, Hebei province, Jan. 29, 2022. An Lingjun/People Visual)