 Radio Script 2001 __________________ Avalanche!
STORY: Jill Fredston spends her winter days either teaching people about the dangers of avalanches or, all too often, digging people out of them. Fredston is an avalanche specialist and codirector of the Alaska Mountain Safety Center, based in Anchorage. She says more people are getting into trouble in the backcountry. FREDSTON: "The number of fatalities nationwide has been increasing. That makes sense because there's more and more back country travelers out there in the winter and equipment has gotten better and better, so we're jumping into terrain that we didn't use to (go into)." It used to be that the backcountry was accessible only to those people experienced enough to ski or climb into it. While Fredston used to get calls to rescue trapped skiers and climbers, she says snowmachiners are now the ones getting into the most trouble. FREDSTON: "The statistic that's really been changing in recent years is that we're having more and more snowmachiners getting caught. These snowmachines are powerful. They can travel into steep terrain under a broader variety of snow conditions. We've had quite a few more fatalities in recent years. In the old days you had to be a pretty good rider to get up into country that could potentially kill you. Now, sometimes the people I dig out of the snow, are people for whom it might be their first day on a snowmachine." In Alaska, 13 snowmachiners died in avalanches in just a six-week period during 1999. Last year, seven people died. And so far this year, three people have been killed. Fredston, who's been teaching avalanche safety for 20 years, says most of the snowmachiners who died were practicing what's called "highmarking." That's where a snowmachiner races up steep a mountain slope as high as possible. The maneuver is risky because it can trigger an avalanche that can kill the highmarker as well as onlookers. FREDSTON: "I think the most important thing to remember is that avalanches don't happen by accident. They happen for reasons. We tend to portray them, the media portrays them, as these freak events—that avalanches come roaring out of the mountains and nail us as innocent victims. About 95 percent of the time it's our weight on or near the slope that causes the problem." Fredston says that in a way, this is good news, because it makes it possible to teach people how not to be the avalanche trigger. FREDSTON: "We tend to think too much like people when we're in the mountains. We make our decisions based on human factors like, 'Well, there's a track on the slope, so it must be fine.' Or, 'It's a blue-sky day, what could happen to me?' Or, 'I've been here a hundred times before and nothing's ever happened.' Really, when we're in the mountains we need to think like a mountain." Fredston says avalanches happen as a result of the interaction between three variables. First is the terrain. Is the slope steep enough to carry a slide? Next is the snow: The snowpack consists of a combination of strong and weak layers. Finally, weather plays a role in avalanches. Fredston says understanding the variables is key to seeing the clues to an avalanche. FREDSTON: "Most of the time when I go to an accident site, the clues are all around. It's not a matter of there were just one or two and they were very subtle. It's usually three or four or five. The best one of all is that there are avalanches on similar slopes, facing a similar way, and of a similar angle. That clue isn't always there, but when it is we don't want to ignore it. There are whoomphing noises—the collapse of a weak layer. There are shooting cracks, indicating that the slab is wound up, that it has elastic energy like a rubber band. That makes it possible to propagate a fracture across the slope. Maybe the snow is really wind-loaded. In other words maybe strong winds have redistributed the snow. You need to be particularly suspicious of these leeward slopes. Maybe there's hollow-sounding snow. That says there is a less-dense, weaker layer." Although Fredston has seen her share of tragedy on Alaska's mountains, she doesn't believe highmarking should be banned. She says there are ways to make it safer. FREDSTON: "One of the scenarios we see all the time in snowmachiner accidents is that one person goes up the slope and gets stuck. Another person then comes to help, and now you have 1,000 pounds of force all tweaking the snowpack in the same place. Or the person comes up above that stuck person and is going to turn down and help them and ends up triggering a slide down onto the person below." Fredston's advice: let the stuck person dig himself out while you watch from a safe distance and prepare to lend a hand if an avalanche occurs.
OUTRO: This is Arctic Science Journeys Radio, a production of the Alaska Sea Grant Program and the University of Alaska Fairbanks. I'm Doug Schneider. Audio version and related Web sites Thanks to the following individual for help preparing this script:
Jill Fredston, Codirector Arctic Science Journeys is a radio service highlighting science, culture, and the environment of the circumpolar north. Produced by the Alaska Sea Grant College Program and the University of Alaska Fairbanks.
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