Is sunspot activity seasonal and are we now in a 'high' season?

The sunspot cycle is about 6 - 11 years long and we are currently in Cycle 23 which began October 1996 and reached a maximum during 2000. Sunspot activity, however, is not 'seasonal' in the sense of being related to Earth seasons. Like terrestrial weather which has a definite seasonal variation due to the inclination of Earth's rotation axis, 'space weather' is driven by the rise and fall of solar activity. We don't really understand why the Sun has these activity cycles, or why they seem to come to a halt all of a sudden ( during the 1600's plenty of astronomers watched the Sun, but sunspots were a rarity). As for being in the 'high' season during 2000, it all depends on which aspect of space weather you are tracking. Sunspots definitely peak at maximum...by definition. But the most severe episodes of solar flares, coronal mass ejections, and geomagnetic or auroral activity, reach their peaks in the year just before, and the year just following, the maximum of the sunspot cycle. For the best flares and aurora the years 1998-1999 and 2001-2002 will probably not be dissappointing!


Copyright 1997 Dr. Sten Odenwald

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