Solar cycle

(redirected from Sunspot cycles)
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This is because the identified fluctuations in the intensity of solar irradiance are unusual at present: whereas the so-called sunspot cycles each lasted eleven years in the past, for unknown reasons the last period of weak solar irradiance lasted 13 years.
But I've never considered the effect of sunspot cycles, which can dramatically disturb the earth's geomagnetic field.
The sun has sunspot cycles that last about 11 years, which begins with minimum activity, ramps up to maximum activity in about 5.
The BAA Aurora Section monitors auroral activity and the records show how it varies with the sunspot cycles.
At issue is whether such changes can be driven by human activity--as opposed to, say, sunspot cycles or other natural factors.