Varying Solar Heating of the Upper Atmosphere

Varying Solar Heating of the Upper Atmosphere

. During the Sunís 11-year activity cycle, the upper-atmosphere temperatures fluctuate by factors of two, and neutral and electron densities by factors of ten. Enhanced magnetic activity on the Sun produces increased ultraviolet and X-ray radiation that heats the Earthís upper atmosphere and causes it to expand, resulting in higher temperatures and greater densities at a given altitude in our atmosphere. (Courtesy of Judith Lean.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University