NEW DELHI — The Sherpas always go first, edging up the deadly flank of Mount Everest while international clients wait for days in the base camp below.
They set off in the dark, before the day's warmth causes the ice to shift. They creep one by one across ladders propped over crevasses, burdened with food and supplies, all the while watching the great wall of a hanging glacier, hoping that this will not be the year it falls.
On Friday, however, it did.
About 6:30 a.m., as the Sherpas were tethered to ropes, a chunk of ice broke off, sending an avalanche of ice and snow down into the ice fields on the mountain's south side and engulfing about 30 men. The toll, at 12 dead with four still missing, is the worst in a single day in the history of Everest, climbers and mountaineering experts said.
The disaster has focused attention on the Sherpas, members of an ethnic group in Nepal known for their skill at high-altitude climbing, who put themselves at great risk for the foreign teams that pay them. Among their most dangerous tasks are fixing ropes, carrying supplies and establishing camps for the clients waiting below, exposing themselves to the mountains first.
A Sherpa typically earns around $125 per climb per legal load, which the government has set at around 20 pounds, though young men will double that to earn more, guides say. Raised on stories of wealth earned on expeditions, they also have very little choice, coming from remote places where there is little opportunity other than high-altitude potato farming.
Friday's avalanche, which killed no foreigners, left many thinking about this calculation.
"All the hard work is done by Sherpas; that is the reality," said Pasang Sherpa, of the Nepal National Mountain Guide Association. "The client will say, 'I did the summit three times, four times.' That is our guest, and we have to accept it. Our job is to make a good scale for the clients, to make this comfortable. We have to do that."
The Sherpas were spread out at an elevation of about 19,000 feet when the avalanche hit, crossing a notorious area known by some locals as the Golden Gate because of the shape of its ice formations, Pasang Sherpa said. Climbers try to pass it as quickly as possible, but have no choice but to edge across ladders one by one, stretching the crossing to 20 or 30 minutes, he said. Typically, he added, the teams try to cross before sunrise, when rising temperatures may cause shifts in the ice.
"This morning, our friends started a little late," Pasang Sherpa said. "They arrived at quarter to seven."
Tim Rippel, who is leading a group of mountaineers on the mountain with his company Peak Freaks, wrote that the Sherpas had been moving slowly, hauling "the mountainous loads of equipment, tents, stoves, oxygen and so on up to stock camps." He was on the phone from base camp just before 7 a.m. local time when an ice chunk began to fall, causing the avalanche, said his wife, Becky Rippel.
The mountaineers were following a popular southern route up Everest from the Nepalese side, but this route means they have to pass underneath the western shoulder and its moving glacier. Tim Rippel had been watching the glacier, which is a well-known problem, in recent days but did not think it looked as dangerous as it had in the past, Becky Rippel said.
In an update on the company's website a few hours later, Tim Rippel described watching search and rescue efforts.
"Everyone is shaken here at base camp," he wrote. "Some climbers are packing up and calling it quits, they want nothing to do with this."
Between 350 and 450 Sherpas are hired above the base camp during the two-month climbing season, said Richard Salisbury, who works on the Himalayan Database, a record of Everest climbs. Apoorva Prasad, founder of the Outdoor Journal, an Indian lifestyle and adventure magazine, described it as "very dirty work," laborious and dangerous.
"These are the guys going up the mountain every season in the least safe way possible," he said.
The worst recorded disaster on Everest had been a fierce blizzard on May 11, 1996, that caused the deaths of eight climbers.