Like Mr. Fowler, mountaineers around the world find themselves forced to adjust to a warming world. Routes that were icy or glaciated in the middle part of the past century, when the world’s highest peaks were being conquered for the first time, are turning into unstable and unappetizing rock.
David Breashears, who has climbed Mount Everest five times since 1983 and heads GlacierWorks , a nonprofit climate-change awareness group, said significant changes had occurred on the icefall just above the Everest base camp.
Sherpas and other guides have reported that it is “getting much harder to maintain the ladders and the ice screws and the fixed ropes in the icefall,” Mr. Breashears said. The ice screws, which help anchor things in place, now melt out earlier in May, he said.
...Scientists like Mr. Schlüchter cautioned that not every rockfall could be attributed to the climate.
Unlike some years, 2011 has been remarkably safe on Mount Everest. At least 428 people have reached the summit during the spring climbing season compared to four deaths, according to EverestNews.com.
Mount Everest has an extreme climate. The summit temperature never rises above freezing or 32° F (0° C). Its summit temperatures in January average -33° F (-36° C) and can drop to -76° F (-60° C). In July, the average summit temperature is -2° F (-19° C).
...The least safe year on Mount Everest was 1996 when 98 climbers summitted and 15 died.