Solar Sunspot Mystery Continues
Sunspots remain AWOL! Where are they? What do their fewer numbers mean?
The March 2013 sunspot number is out and, according to the Belgium Royal Observatory, it is only 57.9. Belgium is the official keeper of the records that NOAA plots each month.
This month’s number is up from the puny 38.0 recorded for February, but still well below the 90 predicted by NOAA’s Space Weather Prediction Center and half the historical average of 119.
Burr… cooler temperatures could be on the way.
Solar Cycle 24 Trend
During the current solar sunspot maximum (Solar Cycle 24) there have been only 4 months at the end of 2011 where the sunspot number topped a piddly little 70.
A secondary peak is expected the end of this year. If history repeats itself, that peak will be smaller than the first 2011 peak. That means the official annualized sunspot high for Cycle 24 will be around 65. That will make it the lowest peak in over 100 years.
But, compared to the past, it may turn out to be even lower than that because of a recording error dubbed sunspot “inflation”.
The Sunspot Number Workshop
Solar experts have discovered that sunspots have not been recorded consistently over time. Group and individual methods of counting got intertwined.
As a result, since about 1945, sunspot counts have been inflated about 1.2 times higher than before 1945. Top solar physicists are in a series of meetings to define a correction. The group is called the Sunspot Number Workshop. They have had 3 meetings so far with one more scheduled. The most recent meeting was in late January 2013.
In the end, the group will write a paper recommending a corrective solution. It’s a big deal.
When that happens Solar Cycle 24’s peak will look smaller compared to older solar cycles. It’ll make the recognized Modern Grand Maximum disappear and Cycle 24 will then become the smallest peak in 200 years, going back to the Dalton Minimum of the early 1800s.
Currently, they lean toward increasing all the older sunspot counts by 1.2. But no matter what they decide, it will change the comparison between modern counts and those recorded before 1945.
Peering into the Future…
What does the decline in sunspot numbers mean?
In itself, nothing. But that is not all that is going on. There are other changes afoot, according to solar physicist Leif Svalgaard of Stanford University and of the Solar Number Workshop.
According to Svalgaard, a prolific researcher, and other researchers…
Since 1990 there are:
- Fewer sunspots per group
- Fewer small sunspots
- Fewer sunspots per unit of F10.7 magnetic flux
- A declining magnetic flux for the sunspots there are
- Fewer and less intense CMEs
- Less solar wind
- Total solar radiant energy output is less during low sunspot activity
- These changes have progressively accelerated since 1990
Svalgaard says we are entering a new low-activity sun phase that he is comparing to the Maunder Minimum of the 1600s. At that time there were almost no sunspots at all and no sunspot cycles for 70 years.
Svalgaard is quick to point out that declines in total solar energy output during low activity phases can’t explain the drop in temperatures during the Little Ice Age.
Climate scientists talk about forcing mechanisms that drive climate change. Perhaps small variations in solar irradiance and particle flux decreases in the solar wind at Earth combine to act as a climate forcing mechanism to lower temperatures.
That’s pure speculation. Nobody knows. But we will find out over the next couple of decades.