The report on the avalanche was published yesterday on National Geographic's website. It includes a "before and after" satellite photo of Everest, with the first image taken on April 7, and the second on April 26. The avalanche occurred on April 18. The location of the large serac is outlined in yellow on both images, and is clearly missing in the second photo, which gives us a sense of the scale of the avalanche as well.
The research presented in the article comes our way courtesy of National Geographic's senior editor and cartographer Martin Gamache, who says that the surface area of the ice block prior to collapse was roughly the size of an NBA basketball court, and it towered more than 113 feet (34.4 meters) in height. He estimates that it weighed approximately 31.5 million pounds (14.3 million kilograms), which gives you an idea of the amount of force that hit the climbers on the mountain that day in April.
Exactly what caused the collapse remained a mystery, but Gamache chalks it up to gravity. He says that is the force that is generally the cause of these kinds of accidents. There has been some speculation that climate change may have played a role as well, with warmer temperatures possibly allowing large chunks of ice to become unstable over time.
The results of Camache's study coincide with the release of the November issue of National Geographic Magazine, which contains a number of stories revolving around the Everest tragedy. Amongst them is "Sorrow on the Mountain," which recounts the events of that day in detail. Another article takes an in-depth look at Sherpa culture, and what drives those strong men and women to live and thrive in the harsh Himalayan environments. The issue is on newsstands now and available to download in electronic format as well.
This is more fascinating coverage of what is undoubtedly the adventure story of 2014.