Snow cannons! Every year they ensure that the winter sports season starts on time. Most of the ski resorts supplement the amount of natural snow on their slopes with artificial snow. On this page, we explain how snow can be produced and how this technology interacts with our natural environment.
The technique of making artificial snow
Especially in autumn, when there hasn’t been much snow yet, or in spring, when the snow is already melting, the slopes that have been made with artificial snow can be easily recognized. The whole landscape is green and brown except for a few white stripes.
Artificially produced snow consists of water that is extracted from nearby streams and (storage) lakes and is pressed through the fine nozzles of snow machines at high pressure. This produces tiny droplets, which, when cold, freeze as soon as they come out of the nozzles. As grains of ice they fall to the ground. The drier and colder it is, the better snowmaking works.
Photo: Hartmut Wimmer, Outdooractive Editors
Properties of artificial snow
Slopes that consist of artificial snow are often very hard. Artificial snow flakes are much smaller and more compact than natural ones. The entire snow cover has a higher density which also means that artificial snow melts much more slowly than natural snow.
Effects of artificial snow on our vegetation
Experts from the Institute for Snow and Avalanche Research investigate how artificial snow affects soil and vegetation. On the one hand, the research results show that the additional amounts of snow protect plants from injury by ski edges or groomers. In comparison, slope levelling – i.e. straightening the ground – has a much harsher effect on vegetation than snowmaking.
On the other hand, making artificial snow means that slopes melt later than natural snowfields, so the start of summer for flora is delayed. As a result, the vegetation composition can be disturbed in the long term. Plants that manage to develop in a short time will displace those that need more time to produce fruit and seeds.
Another disadvantage is that more water is consumed per season for snow-making on the ski slopes in the Alpine region than is used by a city of 1.5 million inhabitants within a whole year. The production of artificial snow uses as much electricity as a city of 500.000 inhabitants consume in a year.