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In the early hours of Friday morning, five South Koreans and four Nepali guides died during a violent snowstorm. It was the deadliest accident in Nepal’s climbing community since 2015, and those that passed away included decorated Korean team leader Kim Chang-ho. Whilst everyone agreed on the scene of total destruction, there has been much disparity and confusion with regards to an explanation. Media outlets offered varied and often conflicting hypotheses, as presented in our article: 9 Climbers Die at Gurja Base Camp: What We Know So Far.

The Outdoor Journal has since reached out to Global Rescue (the first on the scene) the National Snow and Ice Data Center (NSIDC), The National Avalanche Center, the climbing community within Nepal, and many local avalanche or safety bodies from around the world. Our goal was to establish exactly what might have caused the devastation at Gurja Base Camp.

THE TIMELINE

The below information is courtesy of Global Rescue, a US-based emergency assistance group and the first on the scene at Gurja Base Camp. They spoke to The Outdoor Journal to offer a first hand account.

On Friday 12 Oct 2018 at 0555hours, Global Rescue was notified by Trekking Camp Nepal of an accident involving Global Rescue members on Gurja in Nepal.

It appeared that an avalanche during a high wind snow storm swept the entire climbing party and staff down the mountain from its basecamp. A helicopter flyover later located the mortal remains of missing climbers and expedition staff by air. Total: 5 Koreans (4 had Global Rescue coverage) and 4 Nepalese. The mortal remains of climbers and expedition staff were reported to be scattered in a 400-500m radius. There was significant debris in base camp area.

Global Rescue deployed personnel to Kathmandu on Saturday, 13 Oct 2018 to coordinate logistics with Nepal and South Korean governments, embassies and families of the Global Rescue members. On Sunday, Oct 14 2018, helicopters using longline rescues retrieved the remains of all nine, transporting them first to Pokhara then to Kathmandu. The remains of the South Korean climbers departed Kathmandu for Seoul the evening of 16 Oct 2018. The Minister of Tourism conducted a ceremony at which Global Rescue was present prior to departure.

The bodies of five South Korean climbers killed on Nepal’s rarely summited Mount Gurja arrive home https://t.co/uQe8OwTR21 — AFP news agency (@AFP) October 17, 2018

THE SCENE AT BASE CAMP

All eye witnesses were in agreement. Helicopter pilot Siddartha Gurung told AFP: “Everything is gone, all the tents are blown apart”. Dan Richards, the CEO of Global Rescue, said that “Base camp looks like a bomb went off” and “at this point we don’t understand how this happened. You don’t usually get those sorts of extreme winds at that altitude and base camps are normally chosen because they are safe places”.

It’s at this point that many stories that can be found online deviate from one another.

CAN WE DISCOUNT A LANDSLIDE?

When the news of this tragedy first broke, The Himalayan Times were the first to report “at least nine climbers including five Korean nationals were killed when a massive landslide buried the base camp of Mt Gurja (7,193 metres) on the lap of the south face of Mt Dhaulagiri in western Nepal”.

However, Bruce Raup a Senior Associate Scientist Senior Associate Scientist at the National Snow and Ice Data Center (NSIDC) told The Outdoor Journal that a “landslide (a large displacement if rock and soil) seems unlikely to me because it was likely frozen in place” and his colleague Richard Armstrong, a Senior Research Scientist at the (NSIDC), explained that “the evidence would be there at the site, rock and other debris mixed in with the camp destruction”.

CAN WE DISCOUNT AN AVALANCHE?

The Kathmandu Post reported that upon arriving at the camp, Nepali climbing guide Lakma Sherpa said “When a team of locals reached the site, it was clear immediately that the camp was hit by snowstorm” and that “officials suspect that a massive avalanche on the mountain may have triggered the snowstorm.” Meanwhile, Shailesh Thapa Kshetri, a police spokesman in Nepal, told the New York Times that it was unlikely that an avalanche had struck the team, because the bodies were not buried.

However, when The Outdoor Journal reached out to the NSIDC for comment, Richard Armstrong couldn’t discount an avalanche. Whilst Shailesh Thapa Kshetri pointed out that the bodies had not been buried, “that would still be the case with a dry snow powder avalanche. Not that much mass of snow collecting along the path of the avalanche, but significant destruction due to the air blast resulting from air being displaced by the powder cloud, which would have a density greater than “clean” air”.

AN ‘AIR BLAST’?

Of all the many accounts that have been suggested until now, Suraj Paudyal, a member of the rescue team is believed was closest to the truth. When talking to CNN, Surjah said that “It seems that a serac [a piece of glacial ice broke] and barreled down the couloir [a gully on a mountainside] from the top ridge of the mountain and the gust created the turbulence washing the climbers and staff from their tented camp at the base camp”.

Bruce Raup, a Senior Associate Scientist at the NSIDC, hypothesised that “A snowstorm might have loaded the slopes above them with unstable snow, which then fell catastrophically in an avalanche. Dry snow and ice avalanches are known to push air ahead of them in a sort of shock wave that can pack hurricane force — enough to scatter a camp. Thus, the “air blast” explanation rings true to me, with the understanding that the air blast was caused by a snow avalanche.”

Bruce’s colleague, Richard Armstrong, a Senior Research Scientist, backed this possibility. “In the case of an air blast there would be no such debris (ice and snow), and in many cases like this, very little avalanche debris, actual avalanche snow that is, just the debris of the camp as damaged by the air blast,” he said.

Speaking on behalf of the National Avalanche Center , Simon Trautman, an Avalanche Specialist, explained that “Air blasts are a pressure wave of air that runs beyond the obvious avalanche front (or deposited debris). This phenomenon is associated with avalanche motion, but is only occasionally observed. One theory is that air blasts are generated when free falling avalanche debris compresses air close to the ground, subsequently propelling the air ahead of the debris. While this may, or may not be the physics behind air blasts, we do know that they can be very powerful and destructive.” Simon’s colleague, Dr. Karl Birkeland, Director of the Forest Service National Avalanche Center added “that while air blasts with smaller avalanches are rare, air blasts associated with large avalanches in big mountains are fairly common. A few years ago the base camp at Mount Everest was severely affected by an air blast associated with a large avalanche that was trigged by an earthquake”. The Outdoor Journal reported on this earthquake at the time.

The Colorado Geological Survey clarifies on their website, that “The air blast zone is usually in the vicinity of, but not necessarily continuous with, the lower track or runout zone. In some cases it may even run part way up the slope across the valley from the avalanche path.”

HOW POWERFUL IS AN AIR BLAST?

Bruce Raup of the NSIDC explained that an air Blast could have hurricane force, but could it have caused the devastation found at Gurja base camp? The Colorado Geological Survey explains, “Air blasts from powder avalanches commonly exert a pressure of 100 lb/ft (2) of force (Martinelli, speech November 8, 1973). Pressures of only 20-50 lb/ft (2) are capable of knocking out most windows and doors.“

The Outdoor Journal would like to thank all of those who contributed to this article.

Cover Photo: Charles Ng, Jalja La Pass. Views of Dhaulagiri (8167 m) & Gurja Himal (7193 m)