The picture is from an article in the National Geographic that talks about the problems at 29,000 feet!
P.S. I have not read this article yet but will be doing so later today and may come back and add some excerpts but unlikely I will add more comments about this issue, since I am no expert when it comes to mountaineering. IN fact, I doubt I ever will be and will likely leave this planet never having gone up one.
Related: Photo essay via Boston.com's Big Picture website with some lovely pictures from 60 years of men and women climbing Mt. Everest ... my favorite, this picture of Mt Everest from 2003 - as seen from "Everest Base camp, Nepal on May 26, 2003. Sir Edmund Hillary's son, Peter Hillary, is scheduled to hold a prayer session and ritual mask dance at the monastery today to commemorate 50 years of his father's and Tenzing Norgay's climb to Mount Everest.