The 41-B crew shot this oblique photograph just moments after slide #5 was taken. Some more fully developed thunderheads can be seen in the same Brazilian storm. When the rising cumulus columns meet the tropopause, or base of the stratosphere, at about 50,000 feet, they reach a ceiling and can no longer rise buoyantly by convection. The stable temperature of the stratosphere suppresses further adiabatic ascent of moisture that has been driven through the troposphere by the 8–11 degree/mile lapse rate. Instead, ice clouds spread horizontally into the extended cirrus heads seen in this photograph, forming the “anvil heads” that we identify from the ground. The finer, feathery development around the edges.of some of the thunderheads is glaciation--water vapor in the cloud is turning to ice at high altitude.
STS 41-B, February 1984. Picture #11-41-2347.