Q: I’m a beginning downhill skier from Colorado who recently had the chance to hit the slopes out East, in Maryland of all places. Yes, there’s something there that somewhat resembles a mountain. (OK, it was more of a very large hill, but I still had a blast). Since I’m accustomed to skiing in high-elevation locales where it naturally snows, I was a bit confounded as to how this perfectly lovely mini-mountain in Maryland was completely covered in powder, even though the area immediately around it was snow-free. I’m guessing the answer is snow that’s artificially produced on-site — either that or they truck it in from Vermont — but I’ve never been quite sure as to how that works. Care to fill me in?


A: Although I’m anything but a seasoned ski bunny (blame poor coordination and the fact that even riding the chair lifts frightens me), I grew up in a family of skiers and snowboarders in Washington state, where just 90 minutes or so from my home were some pretty serious mountains on par with what you’re used to in Colorado. Like you, I was astonished when I laid eyes upon my first East Coast ski resort (it was in New Hampshire). Not that it was in any way less than adequate when it comes to winter recreation, just very much topographically different … more gently sloping than vertical in nature. And like you, I wondered “sure, it’s cold out but not snowing, and I’m certainly not in ‘the mountains,’ so where in the hell did all this snow come from?”


The answer? Snow guns! Snow guns, also known as snow cannons or snow machines, are devices that produce the white stuff using — no surprise here — water and pressurized air. The use of snow guns is quite common at ski resorts in need of supplementary snow, or all of the snow as is the case in climate-controlled indoor ski slopes. And yes, even resorts in not-so-vertically-challenged areas — the Cascades and the Rockies — use snow guns from time to time to ensure the consistency of the top level of snow.


The act of artificial snowmaking was born in the early 1950s at a resort in New York’s Catskill Mountains and has become more advanced and more efficient since then. Still, despite being heavily computerized and much more efficient in recent years, snowmaking is a tricky process that involves nucleators (proteins that ensure a maximum amount of water droplets freeze and turn to snow before reaching the ground), chilly temperatures combined with low levels of humidity (measured by the wet-bulb temperature), and a heck of a lot of energy and water to replicate what a snow cloud would normally do.


Most of the energy in snowmaking operations is consumed by electric water pumps that move water from a reservoir through a pipeline to the snow guns; an air plant that produces cool, pressurized air and moves it through a separate pipeline to the snow guns via hydrant stations placed along a ski trail; and by the snow guns themselves, which often, but not always, require electricity to power a fan with nozzle attachments that propel a snow-ready mist at a greater distance before it reaches the ground. (These are usually called airless or fan guns because they don’t require compressed air.) Depending on the type of snow gun, and yes there are a few types, the device may be installed close to the ground or high up on a tower.


Snowmaking at a ski resort is serious business, and despite the simple elements involved — water and air — it can get quite complicated and more science-y than you might think. HowStuffWorks has a great overview on the technical and meteorological particulars of artificial snowmaking. And aside from ski resorts, I’m guessing you’re wondering if one can actually make snow with a snow gun at home? Yessir, for anywhere between $400 and $1,000 (plus the cost of accessories like pumps and compressors along with electricity), you can blanket your very own backyard with the white stuff and create Frosty, the machine-produced snowman, using a residential snow cannon. But just like large-scale snowmakers, Mother Nature still has to fully cooperate on the temperature and humidity fronts when it comes to creating an artificially induced winter wonderland.


— Matt


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Photo: Max Mayorov/Flickr; MNN homepage photo: Shutterstock

Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.

What's the story with fake snow?
Ski resorts make snow with snow guns, which use water and pressurized air.