We all know about our sun’s eleven year cycle of spottiness, how it gets spottier and less spotty over an eleven year period. Well, not really an eleven year cycle. The cycle ranges between nine and twelve years, eleven being the average of nine and twelve, approximately. The actual average is ten and a half, so you could round it up to eleven or down to ten. I haven’t a clue why eleven is official. The sunspot cycle was discovered in 1843 by Samuel Heinrich Schwabe. It’s official name is therefore the Schwabe cycle.
I can’t figure out why no one talks about the sun’s other cycles. There’s at least four more.
There’s the Wolf-Gleissberg cycle of about eighty years. The number of sunspots in each eleven year cycle goes up and down in an eighty year cycle.
Then there’s the deVries-Suess cycle of about two hundred years. It is based on increasing and decreasing concentrations of carbon 14 in ice cores and tree rings. Carbon 14 is created from regular old carbon 10 when an atom of carbon 10 gets whacked by a cosmic ray. When the sunspot cycle cycles down really low, and there are very few sunspots, the sun’s magnetic field gets weaker and starts letting more cosmic rays hit the earth. Cosmic rays, by definition, come from the cosmos. You know, way out there somewheres.
The Bray-Hallstatt cycle is about 2,300 years long. It’s existence is inferred by not only carbon 14 measurements, but also by beryllium 10 measurements.
There is a proposed solar cycle that hasn’t been named yet. It’s around 6,000 years long.
So what’s it all mean, you may well ask? Well, when you take all these sunspot cycles, and the implied variations in the sun’s energy output, you get things like the Maunder minimum. What’s the Maunder minimum, you may well ask? It was the last time the cycles ganged up and sunspot activity nearly vanished for 70 years, from 1645 to 1715, about the coldest period in the Little Ice Age.
What’s the Little Ice Age, you might well ask? That’s for me to know and you to find out next week.
First shared on the Squatcher’s Lounge Podcast:
For the reading impaired, an audio version of this quasi theory may be found here: