Often called the "Valley of Silence," the Western Cwm is a broad ... the Lhotse Face rises some 3,700 feet, at 40 and 50-degree pitches with some occasional 80-degree bulges.

The expedition will take them to the Western Cwm, where they believe that intense radiation from the sun is melting the snow even when air temperatures are below freezing. As the meltwater refreezes, ...