Time-Lapse of Mount Everest Khumbu Icefall

Considered the Deadliest Section on Mount Everest, the Khumbu Ice Fall has claimed more lives than any other area on Everest. The Khumbu Glacier forming the icefall moves an estimated 0.9 to 1.2 m (3 to 4 ft) down the mountain every day, a speed that opens large crevasses with little warning and suddenly collapses large towers of ice (called seracs), ranging in size that of cars to large houses, that tumble down the glacier from time to time. Most climbers try to cross before sunrise when the icefall, still partially frozen from nighttime cold, is less able to move. As intense sunlight warms the area, friction within the ice structure declines, which increases the rate of crevasses opening and blocks of snow and ice falling. The most dangerous time to cross is generally mid- to late-afternoon.