Guest post by David Archibald
Frank Hill’s summoning up of sunspots from the vasty deep of the Sun’s convection zone reminds me of some Shakespeare (Henry the Fourth):
Glendower:
I can call spirits from the vasty deep.
Hotspur:
Why, so can I, or so can any man;
But will they come when you do call for them?
Frank Hill says that his sunspots will be with us in three to six months. The Ap Index suggests otherwise. There is a correlation between the geomagnetic indices (aa Index and Ap Index) at minimum and the amplitude of the following solar cycle. Earlier this year I produced this graph of the Ap Index plotted against solar cycle maxima when I thought that the Ap Index would bottom out at three, giving a maximum amplitude of 25:
This is June and the monthly average of the Ap Index is 3.1. What is interesting from that graph is that there will be no sunspots if the monthly Ap Index goes below 2. The heliospheric current sheet is telling us that the month of minimum is possibly a year off and the Ap Index is showing no signs of pulling out of its glide slope of 0.28 per month, as shown in this graph:
The Ap Index enters the no sunspots zone in October at its current glide slope. Will it pull out in time? The Sun is bleeding magnetic flux (for a very good reason), so I don’t think so.
Frank Hill has shouted (his words) that there is no correlation between solar activity and climate. Back in a time when those who studied the Sun were armed with not much more than an enquiring mind, William Herschel in 1801 noted the relationship between the number of sunspots and wheat prices. When there were fewer spots, wheat prices were higher. To bring that up to the current day, when there are no spots at all, wheat prices will be the highest ever.
Back to Shakespeare: Hotspur has some good advice for those who study the Sun and draw implications for public policy:
Hotspur:
And I can teach thee, coz, to shame the devil—
By telling the truth. Tell truth and shame the devil.
Leif Svalgaard writes in with some graphs of his own:
Using Aa which goes much further back than Ap, the relationship between Aa and the size of the next cycle has been used by many people to forecast the next cycle. [one of the standard methods]. The data point with the red dot is the predicted Rmax for SC/24 using the polar fields and is plotted at the 2009 yearly average so far of Aa [9.1]
No spots for Aa = 2.4
Aa = 0.2318 (B Vo2)0.9478
Where B is the interplanetary magnetic field in nT and Vo is the solar wind speed in 100 km/s units. E.g. for B = 4 nT and V = 350 km/s, thus Vo = 3.5, we have Aa = 8.55 and Rmax = 57.
Ap is about half of Aa, but the relationship is not quite linear: Ap = 0.2925 Aa 1.204
So Aa = 8.55 corresponds to Ap = 3.87.
If we plot Rmax for the previous cycle (purple plusses) there is no correlation
nano-Tesla
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DA’s report is in contrast to the monkeypuzzle counting system that had 2 sets of sunspot groups counted THIS morning, when 1022 was dead long before sunrise yesterday (22nd June 2009). A counting system, unlike the funny Google ad spots, isn’t a laughing matter.
There are institutions & people out there that need to be taken to task. This will do nicely.
Well, our two duelling solarists say a weak cycle of Rmax between 25 to 60.
Rik Gheysens (00:59:42) :
That’s what I get on my 25+ year-old HP-11C.
Further reading while looking for a variant on that formula:
http://solarscience.msfc.nasa.gov/papers/wilsorm/WilsonHathaway2008a.pdf
http://www.iop.org/EJ/abstract/1538-4357/694/1/L11 says (I forget if we know this prediction):
Y.-M. Wang and N. R. Sheeley
Space Science Division, Naval Research Laboratory, Washington, DC 20375-5352, USA
ABSTRACT. Geomagnetic activity late in the sunspot cycle has been used successfully to forecast the amplitude of the following cycle. This success is somewhat surprising, however, because the recurrent high-speed wind streams that trigger the activity are not proxies of the Sun’s polar fields, whose strength is a critical factor in many solar dynamo models. Instead, recurrent geomagnetic activity signals increases in the Sun’s equatorial dipole moment, which decays on the ~1-2 yr timescale of the surface meridional flow and does not survive into the next cycle. In accordance with the original empirical method of Ohl, we therefore argue that solar cycle predictions should be based on the minimum level of geomagnetic activity, which is determined by the Sun’s axial dipole strength, not on the peak activity during the declining phase of the cycle. On physical grounds, we suggest that an even better indicator would be the total open flux (or strength of the radial interplanetary field component) at sunspot minimum, which in turn can be derived from the historical aa index by removing the contribution of the solar wind speed. This predictor yields a peak yearly sunspot number R max = 97 ± 25 for solar cycle 24.
Print publication: Issue 1 (2009 March 20)
No time to look deeper, sorry.
To David Archibald
Do you have a graph of AP against sunspot activity for previous cycles?
To Leif Svalgaard
You will have to explain yourself more – what is your argument here?
To Frank Hill
How does this tie into your solar jetstream theory? Will not a slower jetstream progression result in reduced sunspot activity?
.
>>>If we plot Rmax for the previous cycle (purple plusses) there is no correlation
Do you mean ‘cycles’ (plural) in this sentence? It makes no sense otherwise.
And what is the difference between the zeros and plusses in this second diagram? Is one Ap and the other Aa? If so, it is not marked correctly.
And anyway, if you use a broad felt-tip, instead of a fine-point nib, I still see a good correlation in these purple plusses. The lower the Aa (or should that read Ap?) the lower the sunspot number.
And just one more observation. There is little difference between these two arguments.
Archibald is predicting an Ap below 2.0, which will result in no sunspots for the next cycle.
Svalgaard estimates that Ap is half Aa, and if you plot 2 x 2 = 4 on his Aa graph, you end up with an Rmax of sunspots for the next cycle of just 15 or so.
Very much the same result.
So the critical point here is whether that Aa / Ap trend line will continue downwards. Are there any pointers to whether this will be so, or are there any indications it swing upwards soon?
ralph ellis (06:13:21) :
There is a best-fit line for the purple plusses drawn in, and yes, it has a slope, but r^2=0.1557 which has a fairly specific meaning in terms of the correlation. (tending to imply that if there is a connection, a simple straight-line fit is not the whole story)
Ralph Ellis,
Of course you’re right about the plural with “cycle”.
If I understood the plot correctly, R^2 for the “purple plusses” is 0.1557. That means no correlation. The human eye can dream up a lot of things, that’s why we use mathematical rigor whenever we can.
somewhat on topic:
for years NOAA and NASA have recorded TSI in the 1366 W/m2 range.
http://science.nasa.gov/headlines/y2009/images/deepsolarminimum/irradiance.jpg
Then they launched SORCE and come up with TSI in the 1361 range.
http://lasp.colorado.edu/sorce/total_solar_irradiance_plots/images/tim_level3_tsi_24hour_640x480.png
Why the difference?
Alan the Brit (05:07:23) :
Taking a “lief” out of Herschel’s book, I will be watching the world grain prices over the coming 12 months, whilst keeping an eye on Sunspot activity. Estimates suggest that production may well be down this year already due to poor weather conditions.
—–
I would suggest that current price trends of a now global commodity would bear little relation to the regional production of a crop produced before modern farming practices, fertilizer, weed control, irrigation, seed stocks, price supports, and import/export of surplus production.
http://www.botham.co.uk/bread/characte.htm
Year-to-year yields of small regions over a short-ish time period would certainly be a decent indicator of a growing season’s weather. But even for the length of a single solar cycle you would have to look at many other factors which could change conditions significantly.
I *think* the most measurable divergence between Leif and Archibald (and someone please correct me if I’m wrong here, because I want to keep track of this!) is that Leif has posted that the absolute minimum has already occurred and that we are now beginning to trend up (albeit very, very slowly) while Archibald is predicting that the minimum won’t be reached for another year. (give or take)
I am not taking a “side” in this, but I do very much want to note the measurable predictions and keep track of how they pan out.
Just a basic question here; on your first graph; you are showing an x intercept, and assuming a linear relationship.
Would it make more sense to pitch the outlyer at (10,160) and view it as either parabolic or hyperbolic and show a y intercept (or vertex) somewhere around 50 to 60. I realize I’m in way over my head here, but one of those data points looks seriously like an anomaly in an otherwise nearly normal parabolic distribution, and the data points make this event outside of any current experience. These types of physics functions never seem to be truely linear, at least in my limited experience.
Just a layman’s observation, your patience is appreciated.
rbateman (05:39:48) :
Puttng the counting problem to one side, have you noticed any qualitative difference over time in the Solar Cycle 24 spots?
Ric Werme (05:47:48) :
Wang and Shirley are way out because they called the minimum a couple of years too early.
I do wish we could keep temperatures and solar information in separate threads. I have always been interested in what ol’ Sol is doing but it gets muddied by intrusions of “It’s witch tit cold in Timbucktoo so it must be the Sun what’s causing it.”
Maybe we could have a thread called that and we could discuss there what endogenous variable is to blame for nipply weather in your corner of the world. Can we just talk about the Sun and learn about it before we ascribe connections that are, so far, completely unmechanized!?!?!?!? Please!?!?!?!?!
So to that end, I have a question. Which filtered version of the Sun is best for viewing plages that are there but the lack of heat differences cause the spot to be a Cheshire cat? The reason why I ask is that according to Leif’s charts, while the SSN tanks now and then, the other indices are still creeping up. Is there a filtered view of the Sun that shows this?
“The Sun is bleeding magnetic flux (for a very good reason), so I don’t think so.”
Hi David,
I missed the “very good reason” of why the sun is bleeding magnetic flux. Do you mind repeating it for those of us who missed it?
Rik Gheysens (00:59:42) :
When I give the following input (0.2318 (4 (3.5)^2)^0.9478) in http://www.wolframalpha.com, it gives me 9.27003 (and not 8.55).
My bad. You number is correct. Numbers that depend on it should then be corrected correspondingly. Not that it changes anything, as by input 4 nT and 350 km/s were just for illustration.
MC (05:06:18) :
Livingston/Penn predicted this based on barycenter analysis of the sun.
No, not at all. Based on an extrapolation of their own measurements. They are not barycenter cult followers.
ralph ellis (05:59:58) :
You will have to explain yourself more – what is your argument here?
That Aa for 2009 [so far] is 9.2 and Ap for 2009 [so far] is 4.3, none of which lead to an extremely small sunspot number. Extrapolating to much smaller values of either Aa or Ap is not warranted based of the historical record, although one can always do this just for fun.
ralph ellis (06:13:21) :
If we plot Rmax for the previous cycle (purple plusses) there is no correlation
Do you mean ‘cycles’ (plural) in this sentence? It makes no sense otherwise.
For each minimum [of which there are many] one can plot Rmax for the next cycle [the circles] or for the previous cycle [plusses].
The square of the correlation coefficient [the R2] is 0.8855 for the first case [good correlation], but only 0.1557 for the second case [poor correlation].
ralph ellis (06:21:02) :
Svalgaard estimates that Ap is half Aa, and if you plot 2 x 2 = 4 on his Aa graph, you end up with an Rmax of sunspots for the next cycle of just 15 or so.
Very much the same result.
So the critical point here is whether that Aa / Ap trend line will continue downwards. Are there any pointers to whether this will be so, or are there any indications it swing upwards soon?
The critical point is not whether Ap is half Aa, it is that almost by definition as Ap is measured in 2 nT units while Aa is measured in 1 nT units – I know this is silly, but that is the way it is by historical accident. the point is whether Ap will reach 2 [or Aa 4], and there is no evidence for that.
Mark Wagner (06:52:23) :
for years NOAA and NASA have recorded TSI in the 1366 W/m2 range.
Then they launched SORCE and come up with TSI in the 1361 range.
Why the difference?
This is a difficult measurement and different spacecraft instruments give slightly different results. Probably the SORCE data is the better. The absolute value, whether it is 1366 or 1361, is not really important. What is important is the ‘relative’ precision, i.e. the variation from day to day measured by a single instrument and that is much better, the error is about 0.007 W/m2. So the ‘wiggles’ as seen by one instrument compared with the ‘wiggles’ seen by another agree to with much higher precision than the 5 W/m2 difference between spacecrafts.
Very cool, wet June here in New Hampshire, and currently experiencing a nor’easter stuck off the coast, cranking cool wet weather at us from the northeast for the past few days, continuing into tomorrow. Mostly, daytime highs have been pretty much stuck in the 50’s and 60’s all month, while normally they should be in the 70’s and 80’s. Weather is not climate, but this is truly weird.
I am convinced that cooling is upon us, and that it will continue indefinitely. It can’t come soon enough, to help put an end to AGW/CC hysteria . Those who stand to gain financially and politically from continuing the fraud are too many, and too powerful at this point to stop. But, we sure as heck can throw monkey wrenches into the works and slow them down, as well as Nature doing her part. The actual Deniers are now the Warmistas, who are desperately trying to deny or ignore that we’re cooling, or saying that it’s just part of (manmade) climate change.
TomLama (08:00:36) :
“The Sun is bleeding magnetic flux (for a very good reason), so I don’t think so.”
I missed the “very good reason” of why the sun is bleeding magnetic flux. Do you mind repeating it for those of us who missed it?
Might be hard to do [so I’m also curious]. The Sun is not ‘bleeding’ magnetic flux. On the contrary, the new cycle activity is adding flux to the photosphere.
TomLama (08:00:36) :
“The Sun is bleeding magnetic flux (for a very good reason), so I don’t think so.”
I missed the “very good reason” of why the sun is bleeding magnetic flux. Do you mind repeating it for those of us who missed it?
The reason that Ap [and Aa] is so low now is that the high-speed streams that we often observe occurring in the downslope of a solar cycle are finally dying down and the solar wind speed is getting down below 350 km/sec characteristic of ‘true’ solar minimum. Since Ap [and Aa] depends on the square of the solar wind speed, that has a large calming influence. The magnetic field has not decreased much [and won’t, as new flux is emerging], so the recent decrease of Ap is due to the disappearance of the high-speed streams, and we can’t have less streams than no streams, so Ap won’t fall much more.
Pamela Gray (07:48:57) :
Which filtered version of the Sun is best for viewing plages that are there but the lack of heat differences cause the spot to be a Cheshire cat? The reason why I ask is that according to Leif’s charts, while the SSN tanks now and then, the other indices are still creeping up. Is there a filtered view of the Sun that shows this?
The magnetograms will still show the magnetic fields, and Calcium K-line images will still show the plages, but the best indicator may simply be the F10.7 cm radio flux:
http://www.leif.org/research/TSI-SORCE-2008-now.png
Leif
In the last year of observation, is there anything that causes you to revise downward your prediction of a smoothed sunspot number of ~75?
Dennis Wingo (09:53:32) :
In the last year of observation, is there anything that causes you to revise downward your prediction of a smoothed sunspot number of ~75?
Basically: no. Our prediction paper formally [and on flimsy ground] suggested taking the average polar fields over the three years prior to solar minimum as the predictor. Since the polar fields stabilized at the end of 2003 and have been rather constant since, perhaps it is better to use the average since then as predictor [in which case the value would not change], rather than strictly the average over the last three years, in which case the prediction would be ~70. Both values are not significantly different, so pick yours. Perhaps one in the middle [~72] would be better, but that is just hand waving. In any case, what we really are predicting is not sunspots per se, but the number of magnetic active regions because what goes in is the magnetic field, so that is what comes out. In the past there were 12 ‘spots’ per region, so our prediction is 72/12 = 6 regions. Livingston & Penn may show us that the visibility of these regions changes with time, so perhaps the sunspot number as such may not be a good indicator. Active region count is perhaps better, or average magnetic flux, or F10.7, or Ca-II-K-line, or … It will be interesting to see how the solar community will struggle with this question, should L&P turn out to be correct.
Bruce Cobb says:
This is, of course, ridiculous. Perhaps as ridiculous as the AGW proclamations.
There could be cooling, even significant cooling, which will take some adjusting to. However, it will not be indefinite … at some time the good times will return.