British climber and his guide missing and presumed dead on Mount Everest after reaching the summit. Climbing in 'death zone' above 26,000 feet. Three deaths on Everest this year, 18 last year. Overcrowding and changing weather conditions pose risks.
Key Points
Climbers missing in 'death zone'
Paterson and Sherpa presumed dead
Three deaths on Everest this year, 18 last year
Overcrowding and weather conditions pose risks
Pros
Raising awareness for ovarian cancer during the climb