Artificial snow and Europe's ski season

by Kirsty McCabe, FRMetS

Climate change is already affecting Europe’s snow season, with the use of artificial snow makers on the rise. During the Andorra Weather Meeting, I asked Nico Fornes, snow area technical director of Pal Arinsal and Grandvalira Soldeu-El Tarter, to find out more.

How do artificial snow machines work? Do you still need certain weather conditions?

• We spray pressurised water and air through the nozzles of the snow cannons (7 bars for air and over 20 bars for water). No other additives are used.
• Once sprayed, the finest water droplets quickly form tiny ice crystals. While suspended in the air, the remaining water droplets encounter these newly formed crystals, triggering their own freezing process before reaching the ground as snow.
• We require a wet-bulb temperature of -2°C to begin snow production.

Have you had to use the artificial snow machines a lot this season?

• Snow production this season is similar to recent years.
• In recent years, we have worked hard and invested significantly to produce only the snow we need. To achieve this, all our snow groomers are equipped with snow-depth sensors, giving us precise information about the state of the slopes.

How does it compare to last year?

Last year was challenging. We had to produce about 20% more snow than usual. This season, we hope to stop production early and stay within the average of the last six years.

Are you using artificial snow makers more?

• Usage is increasing. What we notice most is the reduction in production windows (hours available with wet-bulb temperatures below -2°C) and more pronounced temperature fluctuations.
• Each year, we must be better prepared to make the most of the available cold hours.

Is artificial snow the new normal? How long have you been using it?

• Our snowmaking system has expanded over the years. The first snow cannons were installed in the early 1990s.
• Today, we have over 600 snow cannons, covering 66% of the ski area.

Thanks to Nico Fornes and all the team at Pal Arinsal Grandvalira Resorts Andorra.

Further reading:

• Climate change is causing significantly warmer winters across Northern Europe. An analysis from Climate Change assessed how warming temperatures, attributed to climate change, have affected the number of days above freezing during the winter months over a ten year period. In the UK there has been a significant increase in winter days with minimum temperatures above freezing, a nationwide average of 11 "lost winter days". Losing winter's chill affects snowfall, winter sports, water supplies, spring allergies, crops and more.
• No patches of snow from winter 2023/2024 survived to winter 2024/2025 in Scotland, the last Scottish snow patch melting fully on 18 October. This is the ninth time such an event has occurred since reliable records were started in the mid-1840s.