The Science Behind Why You Can Make Snow—Even When It's Above Freezing

Snow is one of the environment's greatest magic tricks, but when Mother Nature's not quite meeting demands, the folks at Hafjell ski resort in Lillehammer, Norway, take matters into their own hands.

While visiting the ski village for the 2016 Youth Winter Olympic Games, YouTuber Tom Scott tackled the science of making snow. The ski resort features about 250 snow guns that pump out the powdery stuff in the form of a well-planned blizzard, keeping the slopes in skiable condition.

The most interesting thing about the snow machines? They work even when the temperature is above freezing. Water and air are forced through nozzles to create a fine mist, and that mist becomes powder instead of rain due to evaporation. When a water droplet evaporates, it pulls in heat from the surrounding environment and cools droplets around it. That process creates nucleation sites and the beginning of snowflake production. If that’s not enough, proteins can also be added to aid the process.

The drier the air, the more water that can evaporate into it, which means that if it’s dry enough, you can actually make snow even if the temperature is above freezing. The converse is also true—high humidity means the temperature needs to be very low, which, as Scott says, is why you’ll never be able to operate a snow gun in the summer.

Hafjell takes its water—a sum of about 30,000 liters (8000 gallons) a minute during a normal season—from lakes at the top of the mountain. See how they recreate the magic in the video above.

[h/t Gizmodo]

Images via YouTube.

By Ben Wittick (1845–1903) - Brian Lebel's Old West Show and Auction, Public Domain, Wikimedia Commons
Photo of Billy the Kid and Pat Garrett, Purchased for $10, Could Be Worth Millions
By Ben Wittick (1845–1903) - Brian Lebel's Old West Show and Auction, Public Domain, Wikimedia Commons
By Ben Wittick (1845–1903) - Brian Lebel's Old West Show and Auction, Public Domain, Wikimedia Commons

Several years ago, Randy Guijarro paid $2 for a few old photographs he found in an antiques shop in Fresno, California. In 2015, it was determined that one of those photos—said to be the second verified picture ever found of Billy the Kid—could fetch the lucky thrifter as much as $5 million. That story now sounds familiar to Frank Abrams, a lawyer from North Carolina who purchased his own photo of the legendary outlaw at a flea market in 2011. It turns out that the tintype, which he paid $10 for, is thought to be an image of Billy and Pat Garrett (the sheriff who would eventually kill him) taken in 1880. Like Guijarro’s find, experts say Abrams’s photo could be worth millions.

The discovery is as much a surprise to Abrams as anyone. As The New York Times reports, what drew Abrams to the photo was the fact that it was a tintype, a metal photographic image that was popular in the Wild West. Abrams didn’t recognize any of the men in the image, but he liked it and hung it on a wall in his home, which is where it was when an Airbnb guest joked that it might be a photo of Jesse James. He wasn’t too far off.

Using Google as his main research tool, Abrams attempted to find out if there was any famous face in that photo, and quickly realized that it was Pat Garrett. According to The New York Times:

Then, Mr. Abrams began to wonder about the man in the back with the prominent Adam’s apple. He eventually showed the tintype to Robert Stahl, a retired professor at Arizona State University and an expert on Billy the Kid.

Mr. Stahl encouraged Mr. Abrams to show the image to experts.

William Dunniway, a tintype expert, said the photograph was almost certainly taken between 1875 and 1880. “Everything matches: the plate, the clothing, the firearm,” he said in a phone interview. Mr. Dunniway worked with a forensics expert, Kent Gibson, to conclude that Billy the Kid and Mr. Garrett were indeed pictured.

Abrams, who is a criminal defense lawyer, described the process of investigating the history of the photo as akin to “taking on the biggest case you could ever imagine.” And while he’s thrilled that his epic flea market find could produce a major monetary windfall, don’t expect to see the image hitting the auction block any time soon. 

"Other people, they want to speculate from here to kingdom come,” Abrams told The New York Times of how much the photo, which he has not yet had valuated, might be worth. “I don’t know what it’s worth. I love history. It’s a privilege to have something like this.”

[h/t: The New York Times]

Name the TV Titles Based on Their Antonyms


More from mental floss studios