Western state wages war against ... snow

Colorado rescue workers are grappling with an avalanche rate that,so far, is triple that of last year.

In Colorado, there are at least two types of snow: the kind that stays on your nose and eyelashes, and the kind you blow up.

Waging war against the stuff Frosty is made of may sound extreme, but it's how avalanche technicians at ski resorts make slopes safe for the public. The unenviable job of using explosives while on skis is a particularly important one this winter, as conditions in Colorado and neighboring states are ripe for avalanches.

"We are in the midst of a very big avalanche season right now," says Alan Henceroth, director of mountain operations at the Arapahoe Basin ski area.

Of the more than 1 million avalanches that slide down the world's mountains each year, about 2,000 are reported in Colorado.

The season here typically lasts from December to March, and already this month a higher number than usual have been reported - about 650, more than triple the number during December 1999.

It's too soon to tell if this will be a record-breaking year, but so far, nature has been preparing the right recipe. Recent storms and high winds have deposited heavy accumulations on an earlier weak snowpack, which is so dry and loose it won't stick together - or to the ground.

Today, people in the West are better prepared for avalanches than they were a century ago, when surprised miners discovered that snow can race down a slope at 80 miles per hour. Ongoing education and research -some of it borrowed from Europe -are helping to protect not only backcountry adventurists, but to forecast conditions for the 2002 Olympics in Utah, and map danger zones as Americans increasingly settle far from urban areas.

"I don't think we're looking at a big crisis, but definitely there's more potential for people moving into avalanche terrain than there was 10 to 15 years ago," says Karl Birkeland, an avalanche scientist at the US Forest Service National Avalanche Center in Bozeman, Mont. Nevertheless, he says, unlike in Europe, where avalanches threaten entire communities, "in the United States we have relatively few buildings that are threatened. So the main problem we deal with in the Western US is people recreating in the backcountry."

Ski areas are especially careful at this time of year. No one has perished in an avalanche at a Colorado resort since 1976, thanks to decades-old measures that include lobbing explosives into snow fields by hand and firing them from boxy weapons called avalaunchers, which are mounted on towers or towed behind snow vehicles.

But even with such time-tested combat methods, preventing avalanches is not always easy. Last week, one cut loose at Breckenridge on a path that had been closely watched and tended with explosives.

"It's the first time I've seen something like that happen in my 17 years at the ski resort," says Jack Rueppel, one of Breckenridge's six avalanche technicians.

The ski patrol quickly swung into action, using snow probes and avalanche rescue dogs to make sure no one was trapped underneath the 200-foot-wide slab of snow. That's a luxury not available in the backcountry, where travelers must rely on one another. To help educate the public, the Colorado Avalanche Information Center (CAIC) in Boulder and other groups teach avalanche-awareness courses - which have grown in number in recent decades and are often filled to capacity.

Most avalanches are "slab" avalanches, where a trigger - like new snow or a human - causes a weak layer underneath to give way, sending a top layer, or slab, down the mountain. They usually occur on slopes that are 30 to 45 degrees, or roughly the equivalent of advanced runs at a ski resort, though most happen outside developed ski areas.

"Avalanche control work is very specialized - and it is very hazardous," says Dan Moroz, one of four snow safety coordinators at Copper Mountain ski area. He and his colleagues can often tell what to expect by looking at activity on slopes around the resort. Between Dec. 18 and 19, for example, he spotted 27 naturally occurring avalanches.

Mr. Rueppel at Breckenridge says the work can be mentally challenging, and sometimes frightening. "The bottom line is we do work with explosives in a very hostile environment," he says, adding that they are not just a bunch of guys "who didn't get enough firecrackers as kids."

One way safety is enhanced is by better prediction tools. One of the latest imports from Europe - the Swiss Nearest-Neighbors Avalanche Forecasting Model - has been installed at the Snowbasin Ski Area in Utah, where some of the 2002 Olympic ski events will be held, and at other US locations.

"It's a really sophisticated way to look through old avalanche and weather databases to come up with the most likely scenario for today," says Mr. Birkeland.

But CAIC director Knox Williams says there is still plenty to be learned about avalanches. "We've been looking at these for 50 years and are still in the infancy" of predictions, he explains.

He echoes what others who've seen avalanches say: "They have an awesome beauty to them, but it's really a beauty that's best observed from a safe distance."

(c) Copyright 2000. The Christian Science Publishing Society

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