Snow gun

Snowmaking is the production of snow by forcing water and pressurized air through a "snow gun," also known as a "snow cannon", on ski slopes. Snowmaking is mainly used at ski resorts to supplement natural snow. This allows ski resorts to improve the reliability of their snow cover and to extend their ski seasons from late autumn to early spring. Indoor ski slopes often use snowmaking. They can generally do so year-round as they have a climate-controlled environment.

The use of snowmaking machines is becoming increasingly common as changing weather patterns and the rising popularity of indoor ski resorts create a demand for snow beyond that which is provided by nature. Snowmaking machines have addressed the shortage in the supply of snow, however, there are significant environmental and cultural costs associated with the artificial production of snow.

According to the European Environment Agency, the length of snow seasons in the northern hemisphere has decreased by five days each decade since the 1970s, thus increasing the demand for the production of artificial snow. Some ski resorts use artificial snow to extend their ski seasons and augment natural snowfall, however there are some resorts that rely almost entirely upon artificial snow production. Furthermore, artificial snow was used extensively at the 2014 Winter Olympics in Sochi, and the 2018 Winter Olympics in Pyeongchang to supplement natural snowfall, and provide the best possible conditions for competition.

The production of snow requires low temperatures. The threshold temperature for snowmaking increases as humidity decreases. Wet bulb temperature is used as a metric since it takes air temperature and relative humidity into account. Snowmaking is a relatively expensive process in its energy use, thereby limiting its use.

Art Hunt, Dave Richey, and Wayne Pierce invented the snow cannon in 1950, but secured a patent sometime later. In 1952, Grossinger's Catskill Resort Hotel became the first in the world to use artificial snow. Snowmaking began to be used extensively in the early 1970s. Many ski resorts depend heavily upon snowmaking.

Snowmaking has achieved greater efficiency with increasing complexity. Traditionally, snowmaking quality depended upon the skill of the equipment operator. Computer control supplements that skill with greater precision, such that a snow gun operates only when snowmaking is optimal. All-weather snowmakers have been developed by IDE.

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Wikipedia