TALKEETNA, ALASKA: At 16,400 feet on Mount McKinley, Eric Roche looked toward the summit, still nearly 4,000 feet distant through deep and perilous snow. Then he looked at the picture of his wife and son, mounted on his ice ax and carried through two weeks of climbing.
And he changed his mind. He would go home.
“The avalanche risk seemed too great,” he said last week as he unpacked his kit in this small town at the foot of McKinley in south-central Alaska. “I feel good about the decision.”
In climbing lore, coming back down the mountain safely is the ultimate measure of a climber’s success, not the number of summits achieved. And around the world this year, it has been a bad season in that respect.
A climbing disaster in the French Alps last week, with nine climbers killed by an avalanche, was only the most recent example in what scientists, mountaineers and parks managers say is a pincer-like motion of forces: more people seeking adventure even as the risks involved are becoming more variable.
From a freakish storm-driven flood in the Great Smoky Mountains in Tennessee that killed two people this month to an avalanche here on McKinley in June that killed four climbers in a place where avalanches are historically less of a worry, the new norm is increasingly the lack of a norm. Patterns of the past can no longer be relied on for guidance.
Since November, at least 34 people in the United States alone have been killed by avalanches, and three of the four worst years for fatalities since 1950 have all occurred since 2007, according to the Colorado Avalanche Information Center.
“The extremes are becoming more extreme,” said Tucker Chenoweth, a mountaineering ranger at Denali National Park and Preserve. Chenoweth trains search and rescue teams on McKinley from the ranger station here in Talkeetna, which oversees the mountain and its expeditions about 60 miles from base camp.
In a strange way, Chenoweth and other experts said, wild places like McKinley are getting wilder, or at least harder to predict.
Sharper seasonal variations of ice and snow and temperature are being repeated all across the world from the Himalayas to the Andes, which scientists say are driven by a higher level of energy in the atmosphere from global warming. As a result, climbers have to think twice about what they might expect one year to the next, or even one day to the next, in places they might have climbed for decades.
On McKinley, the snows this year have been prodigious, and the four avalanche deaths have tied a record last seen in 1987. And conditions have varied widely. This month, a weather station on the mountain recorded a temperature range from 21 degrees above zero to 13 below during a two day period, with 21 inches of snow falling in the middle, rare for July.
“The chances of having an average year are very likely going down as climate variability increases,” said Brian Lazar, the executive director of American Institute of Avalanche Research and Education and a senior scientist at Stratus Consulting, an environmental research company.