The Shishapangma Avalanche - what can be learned ?

Saturday, 18 October 2014

Autumn is almost half way through, and this is not normally a time of year that most people think about avalanches. However, there have in fact been numerous fatal accidents recently so I thought I would have a look at a few of them, and see if there was anything we could learn from them.

Autumn is one of the best times to be in the Himalayas. The monsoon rains have finished and stable weather generally dominates the area. Hence for trekkers and climbers alike this is a great time to visit Nepal.

In September the Double 8 Expedition was in the Himalaya to attempt to climb (and ski) two 8000ers (Cho Oyo 8188m and Shishapangma 8013m), in a week, travelling between them on foot and with mountain bikes. This was a serious undertaking and the team were all exceptionally experienced. Once in-country, after Cho Oyo, the team were joined by two more climbers (Benedikt Boehm and Uehli Steck) who were also keen to set a speed ascent record on Shishapangma. After an aborted summit attempt, the team rested in base camp, before setting out again for the top The following has been extracted from the Double 8 website, and Alpinist.com:

"In the afternoon of September 23rd, 2014 at 4:30 PM (Nepalese Time), Benedikt Bohm (37) and Ueli Steck (38) began their speed ascent attempt of Himalayan peak Shisha Pangma (8,013m) from Basecamp (5,600m). Their plan was to reach the summit in the morning of September 24th, together with teammates Sebastian Haag (36) (who was beginning his climb from Camp 1 (6,300m)) as well as Martin Maier (40) and Andrea Zambaldi (32) (who were starting their climb from Camp 2 (6,800m)). Bohm and Steck joined Haag at Camp 1 (6,300m), as planned, at 8:00 PM. At the same time Maier and Zambaldi departed Camp 2 (6,800m) and headed toward the summit. All five climbers paired up below Camp 3, at approx. 7,100m at 1:00 AM on September 24th, and reached Camp 3 (7,300m) at exactly 2:00 AM. Being the first climbers above Camp 2, the team of five had to continuously break trail through rough conditions as they made their way toward the summit."

Benedikt Bohm's radio message to Base Camp from 7700m read, "the deep, windblown snow is killing us."

150m higher, at 7850m (163m below the summit), Bohm again reported to Base Camp fighting, fighting, fighting. Heaps of snow and high risk of avalanche ... Frustrating!!"

"At 06.55 Haag, Zambaldi and Maier were caught in an avalanche at 7900m and were dragged for 600 vertical meters, over steep ground. Bohm and Steck immediately called BaseCamp for assistance, and descended to Camp 3, via their route of ascent, to attempt a traverse to the avalanche debris. After attempting this for over four hours, they could not find an access route and were forced to abandon their efforts.

Maier, one of the avalanche victims, survived the slide and managed to make his way to Camp 3 on the morning of Sep 25th. He was met there by a Sherpa rescue team, and subsequently evacuated.
The bodies of the others have not been recovered."

Snow and strong wind is the ultimate pre-cursor to avalanche, with snow packed together into a slab. Unfortunately this slab can be fragile, and takes time to bond properly to the layer below. If you trigger the slab (often by standing on it), the cracks propagate (spread), and the slab slides on the layer below.
All the climbers involved were very experienced. They understood snow, and they knew the recent weather conditions. In fact the original team of 3 had turned around near the summit the previous week because of very deep snow.

Yet on the their second attempt, even after acknowledging that avalanche risk was high, they continued, and two people died. So on this occasion it was not a hidden danger - they knew it was there. Hence the only conclusion that can be drawn is that this was a psychological issue - a decision to continue, rather than to descend. I also think we should take note of the fact that the team were almost at 8,000m, without supplementary oxygen, and hence will have suffered from severely restricted cognitive ability (in other words - you just don't think straight when your brain is starved of oxygen). In a subsequent interview with Stefan Nestler, Boehm said: "At our first attempt, the avalanche risk was not the main reason why we turned around. We thought that we were able to control the risk, if we stayed on the ridge. On 18 September (the first attempt), we had just no more energy to climb on. The snow on the ridge was so deep that we sank into it up to our chests."

Nestler added "Before your second attempt, you said that would be definitely your last. Have you set yourself under too much pressure?

It is difficult to know. Pressure is also important. If you are not motivated to the last during such projects at the eight-thousanders, you will not succeed. You need this pressure that pushes you and tells you to do your very best. But of course you also have to keep cool. We have proved this ability, for example in 2012 on Broad Peak, when we returned only 20 meters below the main summit because it was too dangerous. This time, there was unfortunately a short moment without this clear head, perhaps out of the euphoria to have made it almost up to summit. Momentarily we lost concentration, also Basti, who was ahead. Being the one who follows, you do not think about it. Finally, all five are very experienced climbers, they trust each other. But in this case I have somehow reacted, Ueli too, who was close to me. We were really only seven or eight meters apart."

So was this a case of classic heuristics (behavioural habits):

Acceptance Peoples behaviour within a group will often adapt to that group. So group members can be less questioning of the groups behaviour, possibly thinking everybody here is super-experienced, and nobody is talking about the risk, so it must be fine. Nobody likes to rock the boat, but if youre not happy in avalanche terrain, you must speak up and share your thoughts with your team.

Commitment The team had travelled half way around the world and had spent weeks approaching the mountain and acclimatising. They had already climbed Cho Oyo, which was half of their project. They had also turned around near the summit the previous week. While so close (relatively) to the summit of Shishapangma for a second time, it would have been incredibly hard to turn around.

Scarcity - Climbing an 8000m peak is a dream for many mountaineers. Most will never stand on the summit of such a high peak. To climb an 8000er, is in some ways to set yourself apart from the crowd this is the big league. So subconsciously, will people take bigger risks to achieve a goal like this ? Probably.

You have to be prepared to turn around, and forego your summit. Perhaps the team could have waited longer for the snow to stabilise before setting out on their summit bid. Maybe the weather window was short, or maybe they were running out of time I dont know, but should those factors ever influence our decision making in avalanche terrain ? The simple answer is no, however to err is human. Unlike computers, we often make decisions based on emotion if we can learn to control these emotions we will be safer in the mountains.

My thoughts go out to all the friends and families of those involved in this accident. As I am writing this, news is flooding in of another accident in Nepal and I will write on this shortly.