70 Years After The First Successful Ascent, Climate Change Is Making Climbing Everest More Dangerous - Forbes

70 Years After The First Successful Ascent, Climate Change Is Making Climbing Everest More Dangerous
Panoramic view of Mount Everest and Khumbu Glacier as seen from the base camp.

On May 29, 1953, New Zealander Edmund Hillary and his Sherpa guide Tenzing Norgay reached the summit of the 8,849-meters high Everest.

Exactly 70 years later, thousands of climbers have reached the peak, with this year marking a new record for mountaineers expected on Mount Everest during the current climbing season (lasting from April to May) and also deadly incidents.

Of the almost 300 people that have lost their lives in the attempt or reaching the summit, the majority of them have died in or around the Death Zone, the region above 7,900 meters. Here climbers are killed by avalanches or rockfall, by injuries sustained from a fall, from exposure to the elements, from exhaustion or from altitude illness.

When a person dies on Mount Everest, the corpse is mummified by the strong wind and low temperatures and quickly gets frozen into place. Rescuers need to hack the body out of the ice. The frozen body may also have doubled in weight due to the ice. It can take a team of eight people to handle just one body. The recovery of a body is also very dangerous. In 1984, a Sherpa and a Nepalese police inspector were killed when they tried to retrieve the body of a German mountaineer who died on the mountain five years earlier.

An estimated 200 to 250 bodies still remain on Mount Everest, either frozen solid along the climbing routes or buried in the snowfields and glaciers flowing down the mountain. Generally, fatal casualties on glaciers remain immersed in the ice for decades or even centuries. They are moved together with the ice from the site of the accident to the lower part of the glacier to the ablation area, where the loss surpasses the accumulated ice mass.

According to Chinese and Nepalese sources, the discovery of many corpses in the last years shows how rising temperatures are melting the snow and ice cover of the mountain. The highest glacier on the mountain, the South Col glacier, has lost more than 54 meters of thickness in the past 25 years.

Victims killed by avalanches or lost in a glacier crevasse of the Khumbu Icefall, one of the most challenging and dangerous sections of the climb, are now reemerging from the thinning ice. Many bodies were also recovered near Camp IV, the highest camp located at an elevation of over 8,600 meters on a mountain saddle between the peaks of Everest and Lothse. Ten bodies were recovered here in the last four years.

Climate change is also increasing the risk for climbers beneath the Death Zone.

Last June, Nepal's tourism ministry announced plans to move the Everest base camp as the rapidly thinning Khumbu Glacier increased the risk of rockfall and flash-floods at the site, writes Navin Singh Khadka for BBC World Service. A 2018 study by researchers from Leeds University showed that the ice of the glacier close to the base camp was melting at a rate of 1 meter per year, with the glacial meltwater feeding a series of glacial lakes. Such lakes, dammed up by unstable dams of ice and loose rock material, can release their water in sudden outburst floods triggering deadly debris flows in the valley beneath them.