Bejing 2022 run entirely on artificial snow
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For the first time at a Winter Olympics, athletes will compete entirely on man-made snow – in a region with an average annual snowfall of only 21cm and a year-round scarcity of water
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MAN-MADE SNOW
Estimated 220m litres of water required for Winter Olympics

1 Atomisation High-pressure cold water released as fine droplets

2 Evaporation Droplets cool and expand with change in pressure

Water flow
Weather station
Fan
1 2 3 4

100% renewable energy used

3 Nucleation Bacterial fragments added – around which droplets crystallise

4 Convection Fan cools and disperses crystals
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MAN-MADE v NATURAL SNOW CRYSTALS
Varies by moisture content and temperature


Plates: Man-made crystals have less time in air to grow – simple shapes form dense, granular snowpack

Needles
-10 ̊C
Solid plates
-20 ̊C
Thick plates
-30 ̊C -40 ̊C

Natural powder snow forms in low humidity – extreme cold preserves crystal structure to retain light, fluffy texture


Solid prisms
Moisture-starved, low temperature crystals

Hollow prisms
Fine, granular snow

Sector plates

Saturation

Dendrite: Forms at just below 0 ̊C in supersaturated air, or at -20 to -25 ̊C in lower humidity

Most complex structures formed by crystals falling over longer period

TYPICAL CLOUD SATURATION

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Sources: TechnoAlpin, USGS © GRAPHIC NEWS