Water & air - nothing else!

Formation of natural snow

Both natural snow and technical snow consist exclusively of the elements water and air. Snow develops from finely condensed droplets of water which form in the clouds through the cooling and oversaturation of atmospheric air. At very low temperatures, small ice crystals are formed and are drawn to the ground by gravity. As they fall through different layers of air over the course of several minutes, ice crystals grow along their axes, forming typical snow crystals.
The Snow crystals mass together to form snow flakes. Depending types of natural snow are formed ranging from powder and corn snow to wet spring snow.

Basic principles behind snow-making technology

In the same way as natural snow, technical snow consits exclusively of the elements water and air. The only difference is that technical snow is produced by a machine. It is therefore incorrect to talk to "artificial snow". Artificial snow is in in fact plastic or polystyrene snow made for the theater or films. The correct term for snow made from snow-making equipment is "technical snow".
Technical snow is produced by pelicating the natural snow formation. Regardless of the type of snow gun (fan guns or lances), water is atomized into tiny droplets using nozzles. The finely atomized mist strikes the finely atomized water/compressed air mixture which leaves the nucleation nozzles and contains the "nuclides" (= snow cores). The fan gun turbine projects the nuclides and fine mist into the ambient air. As the water/air mixture falls, it freezes into snowflakes.

Climate requirements for technical snow-making

Several parameters must be observed to make snow. The term "snow termperature" is used to refer to the "wet bulb temperature". The wet bulb temperature results from the dry bulb temperature (= the temperature that can be read on a standard thermometer) and the relative atmospheric humidity expressed as a percentage. Due to the wind chill, the wet bulb temperature is always lower than the air temperature. The dryer the ambient air, the greater the difference in temperature. At 100% atmospheric humidity no more water can evaporate and the wet bulb temperature equates to the dry bulb temperature. A low dry bulb temperature and low atmospheric humiditiy provide the optimum confeditions for making snow. The higher the atmospheric humidity, the more unfavorable the conditions for making snow, as the ambient air is already humid and can only absorb a small additional amount of humidity or no more humidity. On snow guns, the wet bulb temperature is measured by the weather station. At the start of the snow season, marginal temperatures very frequently prevail and this represents a major challenge for snow making and snow quality. Ever since it was founded, TechnoAlpin has always been concerned with making snow under these extreme conditions.
If the wet bulb temperature drops, more snow can be produced faster. Also the water temperature plays an essentail role in efficient snow making and producing good quality snow, and ideally is slightly aboce freezing point. If the water is too warm, cooling towers are used to reduce the water to the right temperature.

Snow-making on ski runs...

• helps to offset fluctuations in snowfall during the season.
• enhances skiing safety by assuring a consistent, very high level of snow quality.
• enables skiers to use ski runs close to the valley and the main downhill runs.
• provides snow cover for patchy areas – such as ridges, edges, sunny slopes and entrances – on pistes which are otherwise well covered with snow.

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