Snow avalanches—such as this one seen from Tasman Glacier in Mt Cook National Park—are among nature’s most striking spectacles. Most occur naturally, unseen and harmless, but those that occur around ski fields or roads have claimed the lives of 140 New Zealanders since records were kept.
On the night of August 18, 2001, a slow-moving depression engulfed the Southern Alps and dumped more than 60 cm of snow on the mountains around Wanaka. All of it fell without wind—a rare thing in New Zealand—and by morning lay upon the southern ski fields like an eiderdown.
On such occasions, ski towns in Queenstown, Ohakune, Methven and Wanaka are gripped by ‘powder fever’. Shops are closed, with signs hanging in the windows proclaiming, “Powder day! Back in the afternoon”. Tradesmen down tools and race up hill, and even classrooms are empty (and this despite stern memos from principals that parents are not allowed to take their kids out of school on “powder days”).
That Sunday was the powder day of the season, the biggest in years. As he did most mornings during winter, Dave Harmer drove the ski shuttle bus up the mountain to the Treble Cone ski field, near Wanaka, gave his passengers an orientation talk in the carpark and ensured they all knew the departure time. He did his talk on the double, eager to hit the slopes himself. Like most seasoned ski bums—this was his 12th winter here—Harmer did not work for money, but for the opportunity to ski. Driving a mountain shuttle wasn’t much of a job, but it paid for his skiing and allowed him to do it every day.
That day, Harmer teamed up with an old friend, Geoffrey Blackler, another winter local for whom skiing had become something of a spiritual pursuit. They made a good team—quick, competent, intimately familiar with the mountain—and they were finding plenty of fresh lines. But as the day unfolded and powder fever raged, even the most secret runs were getting ‘tracked out’. The two expert skiers ventured farther outside the boundaries of the ski area, always looping back to the lifts for another run. Each was a plunge into ecstasy, a rhythmic dance with gravity.
At the top of another lift they had a moment of indecision.
“C’mon Geoff! One more run!” Harmer enthused.
“Mate, I’m starving,” Blackler replied in his Cockney lilt. “Haven’t got another run in me. Gotta go down to the caf and eat something.”
Harmer hesitated, though only briefly. The pull of the snow was too strong. He had already eaten a muesli bar; that would have to do until day’s end. Having promised to meet up two laps hence, the pair skied in opposite directions. They would never see each other again.
Blackler headed down the piste while Harmer began a long traverse above the ski field, south, towards more untracked snow. A snowboarder joined him, and perhaps Harmer felt safer knowing he was not alone.
Beyond the southern end of Treble Cone there is an area called Hollywood Bowl, a wide slope which steepens as it funnels into a series of couloirs known as the Motatapu Chutes. The snow in the bowl was sheltered and touched neither by a skier nor a breath of wind.
Harmer eased over the edge and plunged in, etching a calligraphic squiggle as his skis sliced into the pale skin of the mountain.
Above him, a massive change had been wrought in the white mantle. There was a muffled whoomph and a fracture line opened, tearing the face of the bowl from the rim crowning it.
The white surface cracked into blocks and the layer of new snow sheared off the hard icy base and began to slide down the mountain, liquefying and gathering speed, funnelling towards the chutes.
If the snowboarder above had shouted, Harmer may not have heard it. He was still moving, and now the entire slope was moving with him, but faster than he was. He fell, his skis came off, and the torrent of snow overwhelmed him, pulling him under its turbulent surface.
The walls of the bowl closed in and the avalanche poured through the narrowing and into one of the couloirs, the way an ocean breaker pounds through a gap between rocks. Moments later, the torrent of snow stopped at the bottom of the chute and all went deathly still. Powder rose in a fine mist and blew with the breeze.
Statistically, most avalanche survivors are dug out within 15 minutes. The chances of surviving a full burial are down to 30 per cent after 20–30 minutes under snow, and they drop off exponentially beyond that.
Though both wore avalanche transceivers—small electronic devices which can be radio-located when buried under snow—the snowboarder could not find Harmer in time, and when the ski patrollers arrived on the scene and located the buried man, it was too late.
“We did all we could,” said Gordon Smith, the ski patroller who led the search, “but if you’re not found by the members of your own team, your chances of surviving a full burial are near zero. The first 15 minutes are the most critical.”
The snow around Harmer’s body had compacted so hard that it immobilised him like a full-body cast. There was a “death mask” around his face, an imprint of his features in the frozen snow.
“He was about a metre down, his body badly twisted, his backpack on his chest,” Smith told me. “He may have been alive for some time after the avalanche had stopped. The snow is just water and air, but when you breathe into it, the warmth of your breath melts the crystals near your face and the water quickly refreezes, creating a layer of ice. You die of asphyxia.”
Dave Harmer was 40 years old.
There are few spectacles in nature which inspire such fear and awe as an avalanche plummeting down a mountainside, creating its own blizzard, boiling and billowing. Science attempts to apply mathematical qualities to these apparently random acts of violence, to describe the way snow accumulates and moves and to interpret its structure. Dale Atkins, a leading snow-rescue expert and researcher, writes that nine-in-ten victims trigger the avalanche themselves.
Like a flash flood, an avalanche is an explosive flow of snow seeking new equilibrium at a lower elevation—indeed, people were once advised to “swim” their way out, as if they were swept by a torrent of white-water. The vast majority of avalanches are natural, their paths etched down the vertical landscape like dry waterfalls.
Snow professionals such as Penny Goddard—who authored Avalanche Awareness in the New Zealand Backcountry, the New Zealand Alpine Club’s definitive book on the subject—distinguish between loose-snow avalanches, which start from a single release point and fan down the mountain, and slabs, which are caused by linear fractures in the snowpack. Of the two, the slabs are more destructive and harder to predict.
Most avalanches occur within the 24-hour period following a snowstorm, explains Goddard. The snow that stays accumulates in layers of differing thickness and characteristics, depending on its density, the amount of sunshine, wind and other variables. If you dig a test pit you can see these layers, like the chapters in a book of the winter’s weather.
Like the Inuit, connoisseurs of snow have many words to describe its quality. One source lists 165 terms; an array from champagne powder, cold smoke, butter, whipped cream, sugar, corn and chalk, to less desirable varieties such as crud, mash, crust and the descriptive elephant snot. But what the avalanche forecasters are most interested in is how these different types of snow bond to one another.
Often, layers stick as if glued and this makes snow safe, says Goddard. But a friable layer such as hoar frost or graupel crystals can create a weakness which persists for days, weeks, even months.
Hoar frost, for example, grows on the surface of snow during cold and clear nights when temperatures linger below freezing. It looks like icy mould, sparkling and beautiful, but under a magnifying glass (which every snow professional carries) it resembles a glassy cityscape, each crystal a miniature high-rise. New snow falling upon this frost buries the crystals but does not break their structure. Tonnes of snow can be perched upon these precarious turrets. All it takes is the weight of a skier, the fine edge of a ski, sometimes even a noise, to trigger the collapse of that fragile layer.
The crystals collapse, Goddard explains, like trillions of tiny domino pieces, and all the snow accumulated on top of them goes down the mountain in one big slide at speeds reaching 200 km/h.
Avalanches occur anywhere with sufficient snowfall and gradient. As a consequence of our maritime environment, New Zealand’s snow is wetter, denser and heavier than in continental climates. Strong winds transport snow to lee slopes, and the lack of trees above the snowline—which in the northern hemisphere anchor snow to slopes—means that even small avalanches here are heavy enough to be lethal.
A unique set of circumstances exists in Fiordland, where wet snow accumulates on slopes near the summits and can entrain trees and debris clinging to the thin soils on steep fiord walls as it thunders down. For this reason, the Milford Road has its own avalanche programme, with helicopter crews monitoring the accumulation of snow and bombing it to trigger controlled avalanches when necessary.
The size of an avalanche is expressed on a logarithmic scale of 1–5, with Class 1 being harmless to humans and anything over Class 3 being increasingly destructive. Fiordland is the only region in New Zealand where Class 5 avalanches occur regularly—they are as big and potentially as destructive as anywhere in the world.
Since 1860, when records began to be kept, some 140 people have died in avalanches in New Zealand, though these figures are skewed by a single event. On August 14, 1863, a year of history-making snowfalls, a huge avalanche buried a camp of gold miners in Otago’s Serpentine Gully, near Dunstan. Fifty men were caught; only nine survived.
Since then, snow slides of varying magnitudes have claimed the lives of musterers, trampers and a hunter, soldiers in survival training, road and ski field workers, heli-skiers and guides. But most fatalities have occurred during climbing and, surprisingly, not only in winter or after snowstorms.
Snow persists in the mountains until late summer, and by then it is saturated with water, extremely heavy and just waiting to slide.
“I was nearly caught out myself once, rock climbing in the Darran Mountains,” says Goddard. “It was summer. We were wearing shorts and not carrying avalanche rescue gear. We crossed a gully and were wandering among the alpine herbs and flowers, carefree and soaking up the sunshine, when there came this tremendous roar from above, a free-falling cascade of snow, and within moments the gully where we had been only minutes earlier was gone, choked to the brim with blocks of snow as big as cars. I still felt sick the next day.”
It seems you cannot know enough about avalanches, and what you might know is no guarantee of safety.
Included in the list of avalanche victims is Dave ‘Snowman’ McNulty, a heli-skiing guide and formerly the country’s leading avalanche expert.
In July 1989, McNulty was guiding a ski trip in the Ben Ohau Range north of Twizel. There was 30 cm of new snow on the ranges, providing fabulous skiing. On a run called Whispering Silk, he became concerned about hard slab conditions below a ridge. As is customary in uncertain conditions, he suggested skiing one at a time, and led off down the hill.
McNulty was 40 m down the face when the snow fractured between him and the group, and a moderate avalanche started to slide towards him. Hearing a warning shouted from above, McNulty managed to ski off the avalanche, seeking refuge under a band of cliffs, but the rift propagated above him, triggering a second and much larger slide which poured over the cliffs under which he was sheltering. A great wave of snow swept McNulty down the hill, and when he was dug out by his fellow guides, he could not be revived.
Deep in the debris of an avalanche, it is silent, dark and surprisingly warm, perfectly still but for the torrent of thoughts raging in my mind. The strongest of these is the gagging fear of being buried alive—fully conscious, yet unable to move.
I have camped in snow caves many times. They are comfortable, if a little snug, but the space around me now feels oppressing and immobilising. A snow cave you can shape and carve, but a snow grave like this shapes itself around you, filling every crevice, pressing in like a concrete corset that crushes your chest.
My backpack has built-in spine protection and I’m lying on it now, knees drawn up into a fetal position. Before being buried, I grabbed the opposite shoulder strap of the pack with one hand as experts suggest; now, holding my face in the crook of my elbow, I create a small air pocket. Other than that, I cannot move. Minutes pass and the cold starts creeping in. I poke at the snow around me with my free hand but it’s no use; it’s like trying to dig through rock with a fingernail. The only sound is the thumping of my heart. I think of Dave Harmer.
So this is what it’s like to be dying under snow.
Suddenly, there is a crunching noise above, a staccato of light and fast footprints. Something punches through the snow and in the fist-size opening, a black shiny muzzle appears, then a pair of dog paws digging so furiously they are a blur. Rocket the avalanche rescue dog explodes into my tomb.
“Good dog, Rocket! Good dog! GOOD DOG!” I greet him, but Rocket ignores me. He’s not finished yet. “Where is it?” He casts about the hole, bouncing off its walls and me, stirring up a flurry of snow. Then I show it to him, his favourite toy—a thick piece of knotted rope—and he clamps his teeth on one end and we play tug of war with much encouragement, praises and swirling snow. I let my end go and crawl out, out into the sunlight and fresh air.
Standing amid the debris blocks of an avalanche that was triggered a day earlier during routine ski field control work, dog handler Matt Gunn grins with satisfaction.
“It took him under ten seconds to find you,” he says, then turns to his dog again, to praise him some more, to reinforce the positive association between a toy rope and saving human lives.
In 1991, Gunn was working at the Ohau ski field when a large avalanche buried a ski lift and three of his friends who were working on it. Two were not wearing transceivers and one of them was found too late. For Gunn, the incident was the inspiration to train avalanche rescue dogs, and his work stimulated similar programmes around the country.
“In New Zealand, people started using dogs in avalanche searches from about the mid-1980s,” he tells me. “Dave McNulty had a dog named Radar, and there were others, but the efforts were largely unstructured and they kind of ran out of momentum and collapsed.”
Gunn had spent holidays on his uncle’s farm from an early age, with plenty of working dogs around him, and reasoned that if there were trained avalanche dog-and-handler teams stationed on ski fields, deployable at a moment’s notice, lives could be saved.
In 2000, he started training his first avalanche dog, named Blizzid, and by 2009, with fellow ski patrollers, established Aspiring Avalanche Dogs, a non-profit charity based at Treble Cone, creating what he hopes will be a template for other ski fields to use. Currently, there are 12 avalanche dog-and-handler teams around the country, and six more are in training.
“Where the dogs can really save lives is in what we call the side-country, immediately out of bounds of a ski field,” Gunn says. “This is not an avalanche-controlled area, but not the full backcountry either. People go charging into these places, often with little or no mountain experience but hyped up on YouTube clips and looking for fresh snow, under the illusion that just because they’re within the cooee of the field it must be safe. It might not be. If they get caught in an avalanche there, and if they can’t be saved by the members of their own group, the dogs may be their only chance of survival.
“Dogs have found people buried under seven metres of snow. They can pick up your scent from 500 m away and make a beeline for you without hesitation. Cast them over avalanche debris and within minutes you’ll know for sure whether people are buried under it. When every second counts, this can mean the difference between someone’s life and death.”
Beyond Hollywood Bowl, in the Treble Cone backcountry, there is a mountain we call Gottlieb. Like many peaks in this part of the Southern Alps, Gottlieb has distinct profiles, some ridged and fluted with gullies, one—like the Matterhorn aspect of nearby Mt Aspiring—a perfect white pyramid. One late-spring day, I stood on its elegant summit with Geoffrey Blackler, peeling the climbing skins from our skis. It was an awkward climb to get here, against the grain of the mountain, but we had made the effort and now the reward was at our feet: a steep descent down the centre of the face, pristine and achingly beautiful, untouched by another skier.
“Do this one for Dave?” I asked.
“Yeah. He’d have loved to be here with us,” said Blackler.
Harmer’s death had struck close to home, and those who knew him are ever-mindful of what his passing taught us. As one avalanche expert wrote, “Good judgment comes from experience and experience comes from bad judgments”, and we have learnt from bad judgments that did not have to be our own. His death taught us to respect the terrain, to look for those fine changes in the structure of the snow. In a way, I thought, Harmer will always be with us.
Looking down the seductive slope of the mountain, I went through the avalanche checklist in my mind. I knew Blackler was doing the same.
He poked at the cornice with his ski pole.
“It’ll be all right. Shall we go?” he asked, and I nodded.
“One at a time though.”
He pushed off the cornice and I watched him find his rhythm, the round crescents of his turns as recognisable as his hand-writing.
Several hundred metres below, now a speck at the end of his deeply carved signature turns, Blackler pulled out onto a high knoll that rose from the slope like an island, a safe spot should any avalanche come down the face. He waved his arms, a signal that he was now watching, belaying me with his eyes. The mountain snow sparkled in the sun, still and silent, magical. A place to play hard but never gamble.
It was my turn to ski.