Each spring, climbers from around the world converge at Everest’s South Base Camp in Nepal, hoping to summit the world’s tallest peak. For the Sherpas guiding them, the journey grows deadlier each year. Rising temperatures are destabilising the Khumbu Icefall, the most treacherous part of the climb. A Nepali-French team has been working on a new route that may offer a safer path up Everest, their work offering a glimpse of how mountain communities are adapting to a warming world.
At lower altitudes, this new route winds through rock rather than ice, featuring a mix of permanent via ferrata infrastructure – steel steps drilled into the rock and fixed ropes to provide added security for climbers. In particular, the route is intended to protect Sherpas, whose work as guides requires them to make the ascent multiple times during each climbing season with different expeditions. It will be the first new path to the summit from Nepal since Tenzing Norgay and Edmund Hillary established the current route with their historic 1953 ascent.
Concerned by the growing risks posed by Everest’s unstable icefall, French mountaineer Marc Batard and Nepali mountaineer Kaji Sherpa began working on establishing this alternative route in 2022. After facing delays due to bad weather, the route is expected to be completed in the autumn, though financing difficulties have thrown up another obstacle.
At nearly 8,850m, Mount Everest, situated within Nepal’s Sagarmatha National Park, is the world’s highest mountain above sea level, and attracts hundreds of mountaineers hoping to reach the summit each spring. The Department of Tourism issued 479 Everest climbing permits in 2023, 421 in 2024 and at least 444 this year.
But the mountain is also succumbing to climate change. Rising temperatures are thinning glaciers, forming supraglacial ponds and destabilising the current icefall route. Experts say that if climate change continues at this rate without sufficient preservation of glaciers, the safety of climbers and Sherpas, and livelihoods of local people, will be threatened.
Warming temperatures accelerate glacial activity
Mount Everest, in the Central Himalayas, is part of the Hindu Kush Himalayas (HKH) range. A recent study by the International Centre for Integrated Mountain Development (ICIMOD) found that the Himalayan glaciers in the HKH region disappeared 65% faster in 2011-2020 compared with the previous decade. This acceleration signals a dramatic shift in glacier behaviour.
Closer to Everest, the Khumbu Glaciers, while not retreating rapidly, are steadily thinning, experts say. A study analysing six decades of glacier mass change around the mountain found that ice loss has increased consistently since the early 1960s, with glaciers thinning by more than 100 metres.
This has direct consequences for mountaineers who rely on the Khumbu Icefall to access Mount Everest and neighbouring peaks Lhotse (8,516m) and Nuptse (7,855m).
Everest’s most dangerous passage
The Khumbu Icefall is the fastest-moving section of the 15km-long Khumbu Glacier and is riddled with crevasses and towering seracs. “Khumbu Icefall doesn’t stay in one place after the ice breaks down. It is not stable,” Kaji Sherpa tells Dialogue Earth. “When huge pieces of ice break, crevasses are made. Due to icefall, accidents happen on [the] route.”
The climbing season of Spring 2014 was one of the deadliest, after an avalanche in the icefall killed 16 Sherpas, bringing the climbing season to a halt. “With climate change, there are increasing chances of loss of life at the Khumbu Icefall,” Kaji Sherpa notes.
Warming temperatures are also accelerating changes on the glacier’s surface. Researchers have observed the emergence of supraglacial lakes – pools forming on top of the ice. These can act like “heatsinks, that eat away the ice, and slowly merge to form larger proglacial lakes [that form in front of or next to a glacier],” explains Tenzing Chogyal Sherpa, a Kathmandu-based cryosphere analyst for ICIMOD. One such proglacial lake, Thyanbo, triggered a glacial lake outburst flood (GLOF) last August, causing severe damage to Thame Village in the Everest region.
A sudden release of water from a lake formed by meltwater from a mountain glacier, which is held back by ice or a moraine (rocks and sediment carried along by the glacier).
⚠️ These floods can be prompted by an earthquake, avalanche or the accumulation of too much meltwater. GLOFs are often extremely destructive, and are a growing threat in the Himalayan watershed.
This pattern of glacial lake expansion suggests that internal glacier temperatures are slowly rising. A 2017 study found that the coldest ice in the Khumbu Glacier was 2C warmer than the mean annual air temperature. This means the internal temperature of the ice was warmer than the air outside, says Chogyal Sherpa, who contributed to the research.
“Glaciers are warming up from the inside and might be more vulnerable to even minor atmospheric warming,” he explains.
A new route: innovation born of necessity
The via ferrata infrastructure, with fixed ropes, offers a more secure alternative to the unpredictable Khumbu Icefall. Already widely used in the Alps, via ferrata routes offer a scalable solution to the dangers posed by climate change.
It presents “a solution to mitigate the risk of fatal accidents and a solution [to ensure] sustainable and adap[tive] mountaineering tourism in the Everest region,” says Antoine Erout, an expedition member for the new route.
The route begins from Gorakshep (5,140m), the last camp for meals on the existing route before South Base Camp, ascending an old trail toward Sundar Peak (5,880m), a path last used decades ago, bypassing the Khumbu Icefall (5,486m). It then reaches the ridge of Nuptse, before an abseiling descent of several hundred metres in the west valley of Everest to rejoin the normal route to Everest Camp 1 (6,065m) and the summit, says Theo Livet, an expedition member who directed a documentary about the route, with another on the way.
“There will be fixed ropes on the via ferrata section for security, and some fixed ropes at points along the path where a fall could be dangerous,” Livet tells Dialogue Earth. These are used with a jumar – a portable handle clamped onto a rope – for additional safety. A mix of vertical climbing and trekking, the route allows some flexibility. “You can walk on the rocks; you don’t have to take the vertical climb,” Livet notes, adding that the vertical climb helps porters carry provisions to higher camps more quickly.
The bypassing of Khumbu Icefall is crucial especially as the growing influx of climbers could destabilise the ice on the existing Nepal route. “Increased foot traffic on the already unstable ice formation accelerates the compaction and cracking of the ice surface continuously,” notes Mohan Bahadur Chand, a glaciologist and assistant professor at Kathmandu University’s Department of Environmental Science and Engineering. “This, along with waste [left by climbers], speeds up the melting along the route, leading to weakening of fast-moving icefalls [such as Khumbu], which is currently accelerated by the increased temperature and changes in precipitation patterns.”
However, the ability of the expedition to complete the route may be in jeopardy. Last month, Batard announced in a Facebook post that the team were unable to complete the route during their latest journey due to a lack of funding, and called on the Nepali government to commit to financing the project. Talks are now ongoing, with the hope of reaching an agreement.
Adapting to climate change in the Himalayas
Sherpas interviewed by Dialogue Earth describe how the Khumbu Glacier has changed over the years.
“It is one of the busiest glaciers in the world,” says Chogyal Sherpa of Khumbu Glacier, on which many mountaineers, tourists and workers live for over three months. “You won’t find such density of people living on a glacier for a long time [anywhere else].”
This prolonged human presence is also affecting the glacier’s climate. “The unpredictability and extremity of weather events – unseasonal snowfall, no snow, heavy snow, too much rain, and sometimes no rain at all – is becoming more frequent,” explains Chogyal Sherpa.
“Snow on the mountains has been melting, exposing rocks,” adds Pasang Nuru Sherpa, who has been guiding the expedition for the new route. “This increases the risks of rock falling, putting lives in danger.”
Despite these dangers, Sherpas must continue working. “We have to raise our families, and risk our lives,” he says.
As Phurba Tsering Sherpa, a tea house owner on the South Base Camp trail whose grandfather summited the mountain 10 times, puts it: working on Everest, there is a 50-50 chance between survival and death. These odds led Phu Chettar Sherpa to leave his job as an icefall doctor after seven years, during which he re-fixed ropes at around 5,000m elevation each season due to the shifting of the Khumbu Icefall. “My family was unhappy with that kind of job because of safety concerns,” he says.
“Glaciers in general react very fast to variations in climate; the Khumbu Icefall is not an exception,” says Erout, adding that “it has become much more hazardous and sensitive to global warming”.
The future of mountaineering in a warming world
In recognition of growing global threats to the cryosphere, the UN declared 2025 the International Year of Glaciers’ Preservation, with 21 March designated as World Glaciers Day. Few places symbolise the urgency of glacier loss more starkly than on Khumbu Icefall, where new crevasses and seracs are formed each season as ice recedes.
Tenzing Chogyal Sherpa, Kathmandu-based cryosphere analyst for ICIMOD
Mountaineers are at the forefront of the climate crisis – their profession is at the mercy of the weather
“No profession is as close to glaciers as mountaineers,” Tenzing Chogyal Sherpa tells Dialogue Earth. “Mountaineers climb them, interact with them and walk on the glaciers. They are at the forefront of the climate crisis. Their profession is at the mercy of the weather.”
Over the years, Chettar Sherpa, the former icefall doctor, has noticed troubling changes. He notes that peaks like Island Peak (6,165m) and Lobuche Peak (6,119m) in the Sagarmatha National Park now appear more like kalo patthar (black rocks), with little to no snowfall in winter. Even the Nepali Everest trail is turning “more and more rocky” – particularly near Crampon Point, where the Khumbu Icefall begins, he says. These changes increase risk for climbers.
“Depending on the evolution of the Khumbu Icefall and possib[ility] of serious accidents with climbers, the new route could soon[er] or later become the normal route to Everest,” says Erout.
The broader impacts of climate change are also affecting local livelihoods.
In Lukla, the main gateway to the Everest region, the weather is notoriously unpredictable. The airport’s operationality is weather dependent, says Chogyal Sherpa. “Bad weather can lead to backlogs, causing cascading effects on bookings,” threatening the region’s tourism-dependent economy, he notes.
As climate change accelerates, bringing more erratic and extreme weather – and with it, rapid glacier thinning – the stakes are greater than mountaineering. What’s under threat is the entire future of mountain life itself – its economies, communities and ecosystems.
“Climbing is the primary income of the local people, and restricting climbing [due to] increased risk [from climate change] will directly affect them and the country’s overall tourism,” says Chand. He warns that there will be “ecological and cultural consequences in terms of water availability for local communities, agriculture, hydropower, and traditional life may be altered”.
Chand notes that a global reduction of greenhouse gas emissions to pre-industrial levels is key to slowing down the effects of climate change on glaciers, snow and permafrost. “We have no alternatives,” he says. “If [ice melting continues], even a new route won’t be sustainable due to the increased risk in these highly fragile environments.”
