We appear to be having a longer than average minimum but I somehow expect that to be over toward the fall. This is just an uninformed guess at the moment based on good old intuition. The interesting question will be how strong and if the climate recovers from the present cool spell in the next year.
It would be fun to get back to having a warming climate for everyone to get excited about, and to reenter the debate on the influence of sunspots. If what I just suggested actually happens, it will be just too good to be true.
The important thing here is that we have a continuing low flux of sunspots presently happening.
I also like to remind folks that during the Maunder minimum, such sunspots described here would have simply been invisible. Watching the cycles for the past decades, it becomes apparent that the driving system never shuts off and that the sunspots are a secondary effect of that driving system that is subject to minor fluctuation reflected in sunspot behavior.
The K7RA Solar Update
There have been no new sunspots since the recent brief three-day appearance of quickly fading sunspot 1013 on February 24-26. It was another Solar Cycle 24 sunspot, but this is not too encouraging, considering how brief and weak it appeared. There are no predictions for new sunspots, but these events tend to occur suddenly. Sunspot numbers for February 26-March 4 were 12, 0, 0, 0, 0, 0 and 0 with a mean of 1.7. The 10.7 cm flux was 69.9, 68.9, 70.6, 69.4, 69.2, 69.1 and 69.7 with a mean of 69.5.The estimated planetary A indices were 2, 8, 5, 3, 2, 5 and 7 with a mean of 4.6. The estimated mid-latitude A indices were 2, 7, 4, 2, 0, 5 and 5 with a mean of 3.6.
This weekend is the ARRL International DX SSB Contest. We can assume conditions will include no sunspots and very stable geomagnetic conditions. NOAA and USAF predict planetary A index at 5 for March 6-12, and Geophysical Institute Prague predicts quiet conditions, March 6-12.
In this bulletin we have been tracking our own flavor of smoothed sunspot number, one based on a shorter period of data (three months instead of one year that the official smoothed sunspot graphs are based upon), and perhaps revealing trends earlier. But the trend goes down again. Now that February has passed, we can take sunspot data from December 1-February 28 to calculate a three month average, centered on January. The total daily sunspot numbers for that period was 208 -- divide that by 90 days and the result is 2.3.
Here are the numbers for the recent past, updated through last month:
Jan 07 22.7 Feb 07 18.5 Mar 07 11.2 Apr 07 12.2 May 07 15.8 Jun 07 18.7 Jul 07 15.4 Aug 07 10.2 Sep 07 5.4 Oct 07 3.0 Nov 07 6.9 Dec 07 8.1 Jan 08 8.5 Feb 08 8.4 Mar 08 8.4 Apr 08 8.9 May 08 5.0 Jun 08 3.7 Jul 08 2.0 Aug 08 1.1 Sep 08 2.5 Oct 08 4.5 Nov 08 4.4 Dec 08 3.7 Jan 09 2.3
Just as Solar Cycle 23 had a double-peak, we are perhaps observing a double bottom, centered on August 2008 and early 2009, or with the second minimum perhaps some time in the near future. We won't know it until it has passed, but it sure feels like a minimum at the moment.
The lack of sunspots has been gaining attention outside of the usual scientific amateur astronomer and Amateur Radio circles, and with so many people commenting on it who have no familiarity whatsoever with solar cycles and sunspots, we are bound to see poor judgment passed on as settled fact. For years, non-scientists (I am one, too) have occasionally attempted to correlate sunspot trends with everything from social unrest, cardboard box production and stock market averages, to climate and hem lengths, with no success -- or at least the conclusions were not reproducible.
About a year ago, some of us witnessed up close the resulting flap when a daily financial news organ grossly misquoted an astrophysicist, claiming he had predicted decades of few, if any, sunspots, accompanied by endless winter. Even though the scientist denied ever saying those things, the story seemed to develop a life of its own, a sort of social virus that spread widely very quickly, nearly impossible to correct.
As a long time fan of contemporary folklore, I thought it might be interesting to track this particular meme, so I used a popular search engine feature in which I registered a particular string (the word sunspot, in this case), and every day it sent me a summary of every new use of this word found on Web sites, in blogs, Usenet newsgroups and newspapers, along with links to these articles. One of the common mistakes I found involved the difference between number of sunspots and sunspot numbers. For instance, the sunspot number is 11 if there is a single sunspot, and 23 if there are three sunspots in two groups. So someone looking at old sunspot records, and seeing a sunspot number of 150 for a certain day, assumes that the appearance of 150 simultaneous sunspots in a single day is a common occurrence.
Or they might take a look at a graph of smoothed sunspot numbers, such as the one here, and complain because the graph had recently changed without notice, or that the graph at the current date was incorrect because it showed the cycle turning up, when that has not happened. What they don't know is that every point on the graph is based on the average of a year of sunspot data and is placed in the middle of that year. So for any points within the past six months, up to half are based on predicted data. If NOAA, for instance, predicts sunspot numbers to rise in the future, it is normal to see the graph rising when in fact the sunspot numbers have not yet increased. Some of the erroneous accounts have pushed some sort of conspiracy theory, claiming that "the government" doesn't want us to know how rare recent sunspots have become.
Sometimes a letter to the editor of a newspaper, or a blog remark, will state -- without attribution to any source -- that the sunspot number for a certain month was only 3. They probably heard somewhere that there were only three sunspots making an appearance one month, when the actual average daily sunspot number for the month was several times that.