Snow on order – NRC

The weather can’t be forced, not even for the Winter Olympics. For white slopes, the Games depend on more than two hundred snow cannons. Because there is hardly any snow in the area for snow sports at this time of the year.

It is not the first time that there is a shortage of natural snow during the Games. In 1980, snow cannons were used during the Games in the American Lake Placid. Sochi (2014) and Pyeongchang (2018) relied heavily on artificial snow. Even the normal winter sports areas can hardly do without snow cannons.

The blazers you see next to the slopes are only part of the snowmaking process, says Michael Mayr per zoom. He is a sales manager at the Italian company TechnoAlpin supplying the snow cannons for the Games. Artificial snow machines, he says, simply turn water into snowflakes. Snow production starts with collecting water in a reservoir. That water is filtered to prevent the snow cannons from getting clogged. Since the water temperature has to be around freezing when it enters the snowmaking, in some cases it is cooled first. Mayr: “In some ski areas, the water comes from nearby streams. Then cooling is not necessary.” Then the filtered, cold water is pumped up the slopes through pipes, to the snow cannons that line the slopes.

In the snow cannons, water and air are blown out through small holes under high pressure, creating a mist of small water droplets. They freeze into snow. This only works if the environment is cold enough (it may be a few degrees above zero) and the humidity is low. Under those conditions, some water droplets evaporate, extracting heat from the surrounding air. This gives other droplets the chance to freeze into snow crystals. These crystals grow into snowflakes because the other droplets freeze to them. Snowmakers can speed up this process by, for example, blowing air out at a higher pressure. Expanding air cools, causing the fog to freeze faster. Snow cannons make several tens of cubic meters of snow per hour.

It is of course not sustainable. Calculated in November The Guardian that about 185 million liters of water are needed for the Games – more than 70 Olympic swimming pools full. And each snow cannon is rated at a few kilowatts — the equivalent of five to ten washing machines. Added to this are the energy costs of cooling and pumping the water. The machines use a few hundred liters of water per minute.

The artificial snow also has advantages. “We can produce the snow precisely – wetter for alpine skiing and drier for biathlon and cross-country skiing,” says Mayr. He used to be a snowboarder, but now he skis. „I like the snow we make for freestylelocations. I think our snow for alpine skiing is too icy.”