Shrinking Atmospheric Layer Linked to Low Levels of Solar Radiation

Science Daily reports that large changes in the sun's energy output may drive unexpectedly dramatic fluctuations in Earth's outer atmosphere.

They report that results of a new study link a recent, temporary shrinking of a high atmospheric layer with a sharp drop in the sun's ultraviolet radiation levels.

The research, led by scientists at the National Center for Atmospheric Research (NCAR) in Boulder, Colo., and the University of Colorado at Boulder (CU), indicates that the sun's magnetic cycle, which produces differing numbers of sunspots over an approximately 11-year cycle, may vary more than previously thought.

The sun's energy output declined to unusually low levels from 2007 to 2009, a particularly prolonged solar minimum during which there were virtually no sunspots or solar storms. During that same period of low solar activity, Earth's thermosphere shrank more than at any time in the 43-year era of space exploration.

One effect of this is there will be less drag on satellites in very low Earth orbit prolonging their life.

Read the full Science Daily report at
http://www.sciencedaily.com/releases/2010/08/
100826152217.htm

Thanks to George Boorer ZL3PN for spotting this item