I received this via e-mail from K7RA. The original document comes from Dr Kenneth Tapping who was quoted not long ago regarding the solar cycle being “the quietest [he’d] ever seen in 25 years”. This was taken to mean that the current solar minimum was historically unusual, and here Dr Tapping explains that this is not so.
I reproduce here the entire document (other than stylistic changes from PDF to the blog, not a word or a graph has been altered from the original):
This note summarizes my current feeling about the state of solar activity and the solar activity cycle. Any conclusions currently in circulation that have been drawn by extrapolating what you see in this note should not be regarded as reflecting my views. My conclusions are in this note. The information used here is freely available and readers are strongly encouraged to get the data, look at it and draw their own conclusions.
The current solar activity is not that unusual. At this point it is completely unjustified to see current solar behaviour as an indication of any departure from its what the Sun has been doing for at least the last 300 years.
Figure 1 shows a plot of solar activity as measured by the solar radio flux monitors operated by the National Research Council of Canada.
Figure 1: Monthly averaged 10.7 cm solar radio flux solar activity index since 1947 (monthly means).
The arrow under the 1964-1977 cycle indicates the length of that cycle, which was a little longer than the others. That same arrow has been copied and put under the last cycle. The length is unchanged. It can be seen that the current solar activity cycle (now ending) has not yet exceeded the length of the 1964-77 cycle. It is also clear that the longish cycle in 1964-77 was followed by further activity cycles - normal solar behaviour. To exceed the duration of the 1964-1977 cycle, the new cycle would have to delay its start at least well into 2009.
Figure 2 shows the 1964-77 and the 1997-? cycles overlaid on the same plot. Once again we can see the last cycle has yet to last longer than the 1964-77 cycle.
Figure 2: The 1964-77 cycles compared. The current cycle (black trace) has yet to last longer than the 1964-77 cycle (red trace).
The 10.7 cm solar flux covers only about six solar activity cycles. Sunspot number data covers at least 300 years. The histogram Figure 3 shows how the durations of the cycles as seen in the sunspot data have varied since 1700. A 13-year activity cycle is not that unusual.
Figure 3: Distribution of solar cycle durations over the last 300 years. The 1964-1977 cycle, having a
duration of 13 years is unusual, but not that unusual.
CONCLUSION: AT THE MOMENT IT IS UNJUSTIFIED TO ASSUME THE SUN IS UNDERGOING A SIGNIFICANT CHANGE IN BEHAVIOUR. ON THE BASIS OF SUNSPOT NUMBER DATA, WE CANNOT ASSUME ANYTHING ODD IS HAPPENING UNLESS THE NEXT CYCLE DELAYS ITS START INTO 2009 OR 2010.
Another week of excitement as the second solar cycle 24 spot appeared…and then disappeared just as rapidly.
I can’t help feeling that with an unprecedented amount of high technology monitoring the Sun with ever higher resolution, the criteria by which a sunspot is defined has become radically weakened to such an extent that it all becomes meaningless.
On Climate Audit commenters noted that the criteria for naming hurricanes had become so weakened that practically any frontal wave in the Eastern Atlantic that persisted for more than a few hours got a name (the so-called “Tiny Tims” of the hurricane season).
So it appears to be with sunspots and Solar Cycle 24. Here is that second solar cycle 24 sunspot numbered for all to see:
Now in order to ascertain that there really is a spot there, I had to first make sure my laptop screen was really clean because it could have been hidden behind a rogue speck of dust and I could have missed it.
Can you spot it? If so, you’re better than I.
Here’s three views looking at the same spot. It may be there in the magnetogram showing the class signs of magnetic polarity reversal and there may be an associated phage (often the precursor of a sunspot) but is there a sunspot?
Meanwhile a few days later, yet another SC23 spot comes into view.
I can’t help but feel that this is all a little desperate. SC24 continues to surprise with its general unwillingness to make an unambiguous appearance.
David Archibald (as reported by Ronald Bailey at Reason magazine):
One of the more remarkable performances was by Australian entrepreneur David C. Archibald during one of the afternoon panels. Archibald is described in the conference materials as “a scientist operating in the fields of cancer research, climate science, and oil exploration.” He also appears to have business interests in some oil fields in Australia. In any case, Archibald made it very clear that he is a big believer in the idea that climate change is primarily driven by the sun. Archibald’s basic theory is that when the sun’s magnetic field strength drops there are fewer sunspots which reduce the amount of particles ejected as the solar wind. Less solar wind allows more galactic cosmic rays to enter the Earth’s atmosphere. Archibald is here relying on studies by Danish physicist Henrik Svensmark which find that cosmic rays do produce cloud condensation nuclei which then might create low level clouds that reflect more sunlight back into space thus making the Earth colder.
Archibald predicts that the next solar cycle, Cycle 24, will produce a weak magnetic field which means that more cosmic rays will enter the atmosphere to create clouds and thus cool the earth. Actually, a 2007 NASA scientific panel was evenly split on the strong/weak prediction for Cycle 24. However, manyresearchers expect that Cycle 25 may be one the weakest in centuries. Archibald ended by boldly predicting that the world will see average temperatures drop by -2.2 degrees centigrade in the coming decade. That’s more than three times the amount of warming the world has experienced over the last century. He also predicted as a consequence that the growing seasons in the United States would be shortened by a total of four weeks, dramatically reducing food production.
Piers Corbyn: astrophysicist and Earth weather predictor at Weather Action (personal communication):
…I would say that solar cycle 24 has NOT yet begun in the sense that we have not yet reached the smoothed minimum normally used to define the transition.
As far as the (Jan 3rd) NASA sighting (’claim’?) of a reverse polarity spot, I don’t suppose there is any doubt that it was seen but I do agree with your implied statement that it doesn’t amount to much.
As a rough estimate we don’t expect any (more/lasting) reverse polarity spots until maybe shortly after mid-March at the earliest.
Paste this into your blog if you wish.
It will be worth referring back to these once SC24 has established itself in whatever form it turns out to be in.
