In the winter of 2011-2012, Stormhunters Mark Robinson and George Kourounis headed across Canada with their cameras in tow.
After several failed attempts to witness a triggered avalanche, they realized their mission was shaping up to be far more difficult than they had ever imagined.
By the time the journey ended, all they'd seen was a few big piles of snow at the side of the road.
In winter of 2012-2013, they tried again.
This time, just to make a little harder on themselves, Mark decided that he would have the avalanche filmed on live TV.
They recruited reporter Kelsey McEwen and camera operator Shawn Legg from The Weather Network's Calgary bureau and headed into Kootenay Pass, British Columbia, just as a snowstorm headed their way.
Their dramatic footage was captured by our cameras and it can been seen exclusively on The Weather Network on Wednesday, March 27 at 7 p.m., 10 p.m. and 1 a.m. ET.
As a lead-in to the broadcast, Mark answered a few questions about his experience and the safety precautions that can be put in place to avoid being trapped in an avalanche.
TWN: Can you describe what you saw and heard during the triggered avalanche?
MR: An avalanche is amazing to watch, but the sound is really what makes it memorable.
Of course, watching a few hundred tonnes of snow coming straight at you is pretty memorable, too.
What amazed me was the speed at which the snow was racing down towards the road. One moment it comes into view at the top of a ridge; the next it’s racing down the last few feet to the road. The thump [and] rumble of the snow hitting the road sounds just like missing the snow pile beside your driveway and dumping it right back down on the concrete, only it’s about a hundred times louder.
The huge cloud of snow that seems to be the avalanche itself is, in reality, just the very light, powdery material that gets easily airborne. The majority of the mass of the slide itself is close to the ground and races underneath the snow cloud. You can’t really see it until the slide finally stops and a huge mass of snow ends up on the road.
A last few rumbles and hisses as the last few bit of snow come to halt and then, that’s it. The slide has stopped and the avalanche is done.
TWN: How long does an average avalanche last?
MR: Minutes, or even less, depending on how far up the mountain the slide started. If the slide begins far up in the mountain the entire sequence can take five minutes or more.
If the slide's start zone is close to the bottom of the valley, the sequence might last only 30 seconds.
TWN: Globally, where do the majority of avalanches occur?
MR: The majority of avalanches occur in the wild mountainous areas of the world, well out of the areas that are easily studied by researchers. Thus, it’s hard to pinpoint the region of the world where the most avalanches occur. However, Switzerland is one area that seems to be the most prolific in terms of controlled and natural avalanches.
TWN: Avalanche air bag backpacks are a hot topic. Some backcountry experts argue they give skiers a false sense of security, what are your thoughts?
MR: I’ve actually put on one of the backpacks and had it go off on me!
What’s incredible is the speed at which the airbag deploys. One tug on the lanyard and the bag pretty much explodes outwards and wraps around your head, ensuring that you’re well protected in the case of being caught in a snow slide.
The bag material is thick, tough and resistant to being punctured. However, having the airbag in no way diminishes a skier’s responsibility of ensuring that they are skiing in a safe area, and in a safe way.
Being filtered through the trees in an avalanche will still do a massive amount of damage to the human body and no airbag will save you completely.
According to Robb Andersen, head of avalanche control in Kootenay Pass, the airbag system will help a skier to stay atop an avalanche as it slides down the mountain.
In other words, it increases the buoyancy of the person trapped in the snow.
One of the best ways to ensure that you survive being struck by an avalanche is to be on top of, or as close to, the surface of the snow when the slide finally stops at the bottom of the valley.
The real advantage to the airbag is that it ensures that the person using it will have the best chance of being buoyant enough to ensure an easy rescue.
[Tune into The Weather Network for a special episode of Stormhunters on Wednesday, March 27 at 7 p.m., 10 p.m. and 1 a.m. ET]
TWN: In your footage, two different methods of triggering an avalanche are shown. Can you explain the merits of each?
MR: The Gazex cannon and heli-bombing are the two main control techniques used in Kootenay Pass.
The basic idea behind avalanche control is to set off small avalanches so that the snowpack doesn't build up to the point that a large avalanche is released.
The Gazex cannons are large, permanent units that use a mixture of propane and oxygen to set off detonations which in turn set off the avalanche. It’s similar to what happens when you accidentally light your BBQ with the lid closed.
The Gazex system is unique to Canada.
The way the system works is that a large amount of propane and oxygen are stored in a shed high above the cannon itself and when the operator triggers the system, the gases flow down from the shed into the “bell” of the cannon and mix.
When there is sufficient mixing, a spark plug sets off the detonation. One of the prime advantages to the system is that the avalanche control technicians can set off detonations at any time, no matter what the weather, amount of sun, etc.
This means that even in the middle of the storm, the techs can bring down small slides to relieve the pressure on the avalanche start zones.
The other advantage is that it’s cheap.
Hiring a helicopter and paying for the high explosive needed for control is expensive. Propane and oxygen are inexpensive, easily obtained and stored.
Helicopter bombing, or heli-bombing, is the simple task of dropping a large bag of high explosive out the side of the helicopter in order to trigger an avalanche.
This type of control is more difficult to use, but can be better for clearing out hard-to-reach avalanche start zones.
Heli-bombing is far more exciting though. It involves getting the helicopter within a few feet of the trees and rocks while simultaneously igniting and dropping a large amount of high explosives. Each one has a two and a half minute fuse.
So you get in, drop the bombs in three different places, and then move out to safe location. It takes nerves, skill and a seriously fast set of reflexes to ensure that the helicopter doesn't bounce off the trees, or rocks, or cliff.
The advantage to heli-bombing is that while the Gazex cannons can clear out specific start zones, helicopters allow the avalanche techs to get in close and ensure that tricky or hard-to-reach areas are clear of snow that might cause a major slide.
TWN: What technologies are being developed to improve and better understand the effects of an avalanche?
MR: Most of the technology being worked on in avalanche research has to do with remote sensing: the better that avalanche technicians know what’s going in the snow pack, the better that they can predict when the potential for avalanche changes.
For example, researchers are using thermal imaging cameras to attempt to find out if they will be able to pick out weak layers in the snow pack.
Other researchers are trying to determine how far avalanches have travelled down mountains in the past and establish safety zones for potential future avalanches.
Tune into The Weather Network for a special episode of Stormhunters on Wednesday, March 27 at 7 p.m., 10 p.m. and 1 a.m. ET.