Posts Tagged ‘Avalanches’

Monday, February 1, 2010

A Short History of Adirondack Avalanches

You can see the Angel Slides from Marcy Dam: two adjoining bedrock scars—one wide, one thin—on the southeastern slopes of Wright Peak. They are a well-known destination for expert backcountry skiers.

The slides got their nickname following the death of Toma Vracarich. Ten years ago this month, Vracarich and three other skiers were caught in an avalanche on the wider slide. Vracarich died under the snow. He was twenty-seven. The other skiers were injured.

It remains the only avalanche fatality in the Adirondacks, but it put people on notice that the avalanche risk here is real.

Several years ago, I wrote an article on the history of Adirondack avalanches for the Adirondack Explorer newsmagazine. I came up with a list of fourteen. Most were triggered by skiers, snowshoers, or ice climbers, usually on steep, open terrain such as a cliff or a slide.

Here are some examples of what I found:

On March 8, 1975, three ice climbers suffered severe injuries when they were caught in an avalanche on a cliff near Chapel Pond. They would have fallen to the bottom if their rope did not get entangled in the rope of a party below them.

A week later, a snowshoer named Roger Harris was on a slide path on Macomb Mountain when an avalanche swept him five hundred feet. He was nearly buried alive. “I was unable to take in a breath due to the snow jammed in my throat and filling my mouth,” he told me, “but I was able to stick two fingers into my mouth and clear the plug.”

In April 1990, Mark Meschinelli, a veteran ice climber, was standing at the bottom of the North Face of Gothics when it avalanched. “I heard this low rumbling,hissing sound,” he said. “I looked up, and the whole face is moving toward me. There was nothing I could do, no place to go. I got buried up to my waist.” Meschinelli dug himself out and climbed the slope.

In March 1997, an avalanche swept two backcountry skiers down a steep slide on Mount Colden. They might have plummeted to the bottom if trees had not stopped their descent. The skiers were bruised but able to ski out.

Avalanches occur most often on slopes between 30 and 50 degrees, and many occur during or soon after a big snowfall. But the business of assessing the risk of an avalanche is complicated. You can find more information online from the American Avalanche Association as well as other websites.

And if you do spend time in avalanche terrain, you should carry the three essentials: beacon, probe, and shovel.

You might also take an avalanche-safety class. The Mountaineer in Keene Valley will teach avalanche safety at the Adirondack Backcountry Ski Festival in March. The Mountaineer also offers avalanche instruction at its Mountainfest each January.

Photo of Angel Slides on Wright Peak from Wikipedia.

Saturday, January 9, 2010

Adirondack Weather: The Strength of Snow

We’ve all seen it: a branch, a fence post, a sign where the snow that fell upon it seems frozen in a perpetual state of falling off, never quite letting go. How does it do that? It’s not like snow is endowed with abs of steel, or, like a snake, has near mythical suspension abilities thanks to overlapping scales. Or does it?

I’ve been taking the time this winter to read up on, well, winter itself. To most folks snow is merely frozen rain, end of story, but there are people out there who make it their life’s work to study snow, in all its glory, and they have discovered some pretty amazing things. I’m not just talking about how every snowflake is different, or how when water freezes it expands and floats. That’s old hat. I’m talking about the hidden characteristics of snow, those little details that make or break winter survival for small mammals and alpine skiers. It’s pretty amazing stuff.

Snow, as it turns out, has three different phases of metamorphism: destructive, constructive and melt. Each one has its own set of characteristics that influence the snowpack around us. We’ll start with the first and work our way through them.

Let’s say it’s a typical winter day here in the Adirondacks. Flakes of snow drift lazily towards the ground, eventually landing to add their fluffy mass to all those that have gone before. From the moment a snowflake forms, it is acted upon by myriad outside forces, wind and temperature not the least among them. Their delicate forms, be they needles or plates, are battered, melted, and reshaped. Ultimately what remains is a rounded grain of ice. Smaller grains are absorbed into larger grains until all the grains of ice in the snowpack are comparable in size. The warmer it is, the faster this happens.

As you can probably guess, each time a small ice grain melds into a larger one, the associated pockets of air around the grains decrease. Bit by bit, the snowpack gets denser. The grains bond together more strongly. As the bonding increases, so does the mechanical strength of the snow. This is what allows piles of snow to ooze over the edge of a supporting structure while never actually letting go, like in the photo above.

Next comes the constructive metamorphism, alternatively referred to as the creation of a temperature gradient within the snowpack. Basically, what happens is this. The snow at the bottom of the snowpack is warmer than the snow on top. This makes sense, since the earth is warm and the air is cold. Because it is warmer below, the snow at the bottom of the pack begins to sublimate, turn from a solid directly into a gas, in this case from ice to water vapor.

It’s a basic property of physics (the Second Law of Theromdynamics) that stuff migrates from areas of high concentration to areas of low concentration. Therefore, the water vapor produced at the lower portions of the snowpack moves upwards towards colder and drier regions. As the vapor cools, it re-condenses on the ice crystals around it, increasing their size and thus their strength. Meanwhile, sublimation continues below, shrinking the size of the ice crystals at the bottom, reducing their strength, and creating what is known as depth hoar, a very loose and fragile type of snow that makes travel easier for the small mammals that run about under the snowpack while at the same time making it more treacherous for alpine travelers – think avalanche.

The final change that occurs in snow is the melt metamorphism. This may seem pretty straight forward: the air warms up, the snow (and ice) melts. Ah, but the devil is in the details, and this is no different with snow.

Fresh snow is nature’s best reflector of shortwave (solar) energy. Translation: it keeps away the heat of the sun, thus reducing the likelihood of melting. However, as we all know, snow rarely stays in that pristine white condition. Road salt and sand, bird seed and old leaves, branches, bits of bark, cone scales…all sorts of stuff gets onto the snow, changing it from the perfect reflector into something that readily absorbs longwave energy, what we commonly think of as heat. This heat is coming from earthbound objects, like trees. Trees are dark; they soak up the solar energy (shortwave) and release it (longwave) to the surrounding environment. This is why trees (and rocks, and buildings) are often seen with a dearth of snow at their bases – it has all simply melted away.

The details of melt metamorphism have to do with energy exchange: the energy released when a solid becomes a liquid, and the energy required for liquids to refreeze, and how this affects the snowpack as the liquid moves downward through the layers. Suffice it to say that at the end of this process, the entire snowpack has reached a uniform temperature.

Rain and fog continue the melting process. Again, we are looking at energy transfer, but this time from the atmospheric moisture to the snowpack. This is directly influenced by the air temperature and the amount of moisture that is penetrating the snow. In the final analysis, as water evaporates and condenses, energy (heat) is lost, which melts more of the surrounding ice, which evaporates, and condenses…until all the solid water (ice) is gone (either liquid or vapor).

What all this sums up to is the simple fact that the snow beneath our feet is constantly, and I mean constantly, changing. From moment to moment it is never the same. This gives whole new meaning to the phrase “there is nothing permanent but change.” So, we should all go outside and enjoy the freshly fallen fluffy snow while we can, for tomorrow it may be gone.

Wednesday, December 30, 2009

14th Annual Adirondack International Mountainfest

If you still want to take courses at the 14th Annual Adirondack International Mountainfest in Keene, you’d better act now.

The festival, which takes place January 15–17 (Martin Luther King Jr. weekend), is nearly sold out. The only seminars still open are an ice-climbing and slide-climbing course on Sunday and courses on avalanche safety.

However, those who love the mountains and are happy to appreciate them from a heated room should consider two events that weekend. At 8 p.m. Friday, January 15, world-famous mountaineer Erik Weihenmayer will give a slide show and lecture. Weihenmayer is the only blind climber to not only have summited Mt. Everest but also the highest peaks of all seven continents. Weihenmayer recently climbed The Naked Edge, a rock-climbing testpiece in Colorado’s Eldorado Canyon, rated a stiff 5.11.

At 7:30 p.m. Saturday, January 16, extreme mountaineer Steve House will also do a presentation. Considered one of the best alpinists in the world, the climber and author has made dozens of dicy ascents up high-altitude snow, ice and rock routes all over the world. He is known for free-soloing (no ropes or partners) massive faces with little gear. In 2005, in one of his greatest accomplishments, he and a partner completed a new route on the deadly, 13,500-foot-high Rupal Face, the most technical of the many dangerous faces of Pakistan’s Nanga Parbat (26,600).

House is also leading an ice-climbing seminar on Saturday but—sorry, kids—that one’s sold out.

The slide shows, $10 each, will be at the Keene Central School on Market Street in Keene Valley, off Route 73 (just follow the cars if you can’t find it). There’s also an all-you-can-eat pasta dinner at the nearby firehouse from 5 to 7 p.m. on Saturday. And you can demo climbing gear for no charge at Rock and River’s manmade ice wall, located at the end of Alstead Hill Lane, located on Route 73 just west of Keene. All events benefit local charities.

For more information, click here.

Friday, December 18, 2009

Weekly Adirondack Web Highlights

Friday, October 2, 2009

Weekly Adirondack Blogging Round-Up

Tuesday, November 25, 2008

13th Annual Adirondack International Mountainfest

The 13th Annual Adirondack International Mountainfest is scheduled for January 16-18, 2008 in Keene Valley. Local guides Chuck Boyd, Emilie Drinkwater, Jeremy Haas, Carl Heilman, Matt Horner, Don Mellor, Jim Pitarresi and Jesse Williams will be returning to offer clinics on snowshoeing, mountaineering, avalanche awareness and ice climbing (pre-register soon). Guest athletes include Conrad Anker (a key member of the search team which located the remains of George Mallory on Mount Everest), LP Ménard (who with fellow Quebecer Max Turgeon climbed a new route up Denali’s 8,000 foot South Face in just 58 hours in 2006), Janet Bergman (who has climbed in Peru, Argentina, Canada, China, Nepal, South Africa and around the US) and longtime climber and guide Jim Shimberg (who has guided throughout North America and the world, including trips to Iceland, Peru, Bulgaria, The Czech Republic, China, Scotland, Thailand and Canada. Jim has climbed in Alaska since 1987, with 7 expeditions to Denali, Mt Hunter, Mt Huntington, and more).

According to the folks at the Mountaineer, who hosts the event:

Telluride Mountainfilm, one of the premier film festivals in the country, opens the Mountainfest on Friday night with a custom compilation of the best films from Mountainfilm’s 9-year history on tour, with a focus on ice climbing and mountaineering videos. This will be preceded by a short slide show by Olaf Sööt and Don Mellor about Alpine Americas, their new book of fantastic photographs and essays about “an odyssey along the crest of two continents.” Both authors will be available to sign books offered for sale before and after the Mountainfilm on Tour presentation. Friday evening’s festivities begin at 8pm at Keene Central School and entry is $12 at the door.

Jennifer Lowe-Anker and Conrad Anker will hold a special presentation about the life of the late Alex Lowe on Saturday evening at Keene Central School. Jenni’s new book Forget Me Not tells a complex and candid story of how three people’s lives became intertwined to a degree that none could have foreseen; Jenni and Conrad will tell the story through a slideshow and readings. Forget Me Not will be available for purchase before and after the presentation, and Jenni and Conrad will be signing books afterward. The evening’s presentation will be preceded by raffles and tomfoolery as well as a short award-winning film by Sam Lowe on the Antarctic. The show begins at 7:30pm at Keene Central School and entry is $10 at the door.

On Sunday evening Janet Bergman will present a slideshow of her often-humorous efforts to satiate the climbing obsession. Janet is a New Hampshire climber and world-class Mountain Hardwear athlete who has climbed in Argentina, India, Nepal, Peru and throughout New England. This show begins at 7:30pm and will be held at the KVFD fire hall on Market Street, just down the street from Keene Central School in Keene Valley. Entry is $10 at the door.

For more information visit the Mountainfest 2009 web page.