This article originally appeared on Outside
On December 21, patrollers at Colorado's Steamboat Resort erected warning signs across the mountain for the throngs of skiers and snowboarders attracted by historically deep powder. The fluffy snowdrifts had transformed every hole and depression on the mountain--specifically the moats surrounding trees--into deadly traps. The placards warned visitors that they could suffocate in one of these holes.
Just three weeks later, a 65-year-old man from Kentucky was skiing with his son near Steamboat's Morningside Park when he tumbled into a tree well. Patrollers found the man within a few minutes of the mishap and performed CPR, but it was too late.
At his home in Seattle, Paul Baugher read about the Steamboat incident and then logged the information into his records. Baugher, 68, is the global expert in a skiing death called Snow Immersion Suffocation (SIS). Two thirds of these cases involve skiers or snowboarders falling into tree wells and choking to death. Since 2001, Baugher has logged every publicized case of SIS in the United States. By his count, the Steamboat incident was the 90th in-bounds death at a U.S. ski resort of this nature since he started keeping track. That's an average of between 4 and 5 SIS deaths at resorts every year.
During the 2021-22 ski season, 57 people died at U.S. ski areas, according to a report from the National Ski Areas Association. This was up from the ten-year average of 40 deaths per year. The leading cause of death was high-speed impacts with trees. Three deaths occurred in 2021-22 from SIS. The previous season seven people died.
"It's more prevalent than people think," Baugher told Outside.
The fuzzy green branches of a pine tree often obscure the well created by the trunk, which can be several feet deep, depending on the height of the snowpack. Loose snow in the pit can act like quicksand for an unlucky person who falls in headfirst. Gravity simply pulls a person's body downward, until the loose snow covers his or her airways to the nose and mouth.
When Baugher was the head of ski patrol at Washington State's Crystal Mountain Resort--a position he held for 30 years--he performed an improvised experiment to study how people react when in an SIS situation. He had ten patrollers--five skiers and five snowboarders--volunteer to be dropped in tree wells filled with powder to see if they could save themselves. The subjects were placed at different inverted angles while wearing their ski or snowboard equipment. Each volunteer wore a safety harness, and could signal to the safety crew for a speedy removal.
"The degree of inversion was the biggest factor in being able to save yourself," Baugher said. "The angle that was closest to horizontal--three out of ten could recover. If you were over 30 degrees, you weren't coming out on your own. Everybody else, no matter if they got their skis off, had to be yanked out."
Baugher said the test confirmed some of the assumptions that he and other patrollers had about how snow immersion kills people. Baugher said the test subjects who were able to get a hand in front of their mouths to create an air pocket lasted the longest before signaling for rescue. Those that moved around did more harm than good.
"Struggling made it worse and often compromised their airwaves quicker," Baugher said. "And you can't stay down there very long. A minute was about the longest anyone could last."
This winter, Baugher has been scanning the web for news of skier fatalities with a careful eye. In his opinion, the historic snow totals in California, Utah, and parts of Colorado have created the deadly recipe for SIS, and he's been reaching out to resorts to remind officials to warn skiers. Baugher has seen patterns emerge in his research into SIS fatalities, and he believes skiers can avoid disaster by learning from his work.
Conditions are most dangerous when there is at least 24 inches of unconsolidated snow in and around trees. This often happens in the 48 hours after a major storm, Baugher says. Fatalities often happen in peak ski season, when temperatures are too cold for surface snow to melt in the sunshine.
Baugher also says the accidents tend to happen in the afternoon--when skiers have tracked out the new powder on cut trails and then head into steeper terrain and glades searching out fresh lines.
"People want to get into steeper and narrower stuff, and that brings you closer to the trees," Baugher says. "People's legs are tired but they still want to get the powder."
Typically, it's a forward-momentum fall that propels a skier into a tree well. Perhaps they bury a tip, or get snagged on a sapling, but their speed takes them toward a tree, and their body's momentum pushes more snow into the depression. And Baugher says a high number of the fatalities involved skiers who were in a group but got separated in the glades.
"Skiing with a partner doesn't work if you don't keep them in sight," he says.
So, what advice does Baugher have to stay safe?
Know the risks. If it's a powder day and you want to ski the glades, understand the dangers that are present in-bounds.
Always ski trees with a partner and stay in visual and auditory contact.
Agree to have regular regrouping points during the descent.
If you fall toward a tree, grab at branches or the trunk to keep yourself from plummeting into the well
If you fall in, don't struggle. Try to keep an air way clear and wait for your partner to help.
Have a clear conversation with your skiing partner prior to the run about everyone's responsibilities. "The old saying 'there are no friends on a powder day' can be lethal," Baugher says.
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