Why the SWPC F10.7 radio flux graph is wrong

Leif Svalgaard writes: “Several people asked why I said that the SWPC F10.7 graph was ‘just wrong’. And I promised a follow up on that. Here it is.”

Happy to oblige! For reference, here is the original graph from SWPC. – Anthony

click for source image

The SWPC F10.7 Radio Flux Prediction Graph

Leif Svalgaard, May 2009

Fitting the monthly average the F10.7 flux (reduced to 1 AU) against the International Sunspot number, R, for the entire interval 1951-2009 to a forth order polynomial gives a formula for computing the Flux from the sunspot:

Flux = 67.29 + 0.316 R + 0.01084 R 2 – 0.006813 R 3 + 0.0000001314 R 4 (1)

The correlation is shown in Figure 1 below:

click for larger image

We know that this formula does not accurately portray the most recent relationship between R and F10.7 (see previous essay), but if we make no assumptions or corrections and just take the data as they are we can consider the conversion formula as indicative of the average conditions the last half century.

SWPC gives a table showing the predicted sunspot Number and the predicted F10.7 cm flux for the next decade. Here are the first few rows of that table, with the middle value of the predicted values in bold script, followed by a high and low limit:

Year Month Predicted Sunspot Number      Predicted F10.7 cm Flux:

```2009 01         2.1     5.1     0.0       67.4    69.4    65.4

2009 02         2.7     7.7     0.0       67.3    70.3    64.3

2009 03         3.3     8.3     0.0       67.2    71.2    63.2

2009 04         3.9     9.9     0.0       67.2    71.2    63.2

2009 05         4.6    11.6     0.0       67.3    72.3    62.3

2009 06         5.5    12.5     0.0       67.5    73.5    61.5

2009 07         6.7    14.7     0.0       67.8    74.8    60.8

2009 08         8.1    17.1     0.0       68.2    76.2    60.2

2009 09         9.7    18.7     0.7       68.8    76.8    60.8

2009 10        11.5    21.5     1.5       69.7    78.7    60.7

2009 11        12.6    22.6     2.6       70.2    79.2    61.2

2009 12        14.6    24.6     4.6       72.1    81.1    63.1```

Using this table we can plot the predicted Flux as shown by the smooth red curve for the next solar cycle [or alt least up through 2015, Figure 2]:

click for larger image

I don’t know how SWPC came by their predicted F10.7, but my best guess is that they ran a correlation like the one shown in Figure 1 and applied it to the predicted sunspot number. Doing this using the observed sunspot number up to last month gives the ragged blue curve with the smooth blue curve coming from the predicted sunspot number. There is a good match for the predicted part of the curves [the red and the blue after May 2009]. The graph on SWPC’s website http://www.swpc.noaa.gov/SolarCycle/ seems to match the smooth curves quite well, with the exception of the variation during 2009, which I show as the purple curve. It is simply incorrect to start the curve from a flux of 60 and inexplicable [to my way of thinking – other than plain sloppiness] why the graph should disagree with the published table at http://www.swpc.noaa.gov/ftpdir/weekly/Predict.txt

As discussed in the previous essay and obvious from the discrepancy between the red and blue ragged curves above in Figure 2, the formula (1) for the average correlation between the Flux and the Sunspot Number does not work so well after about 1989, so it is not clear that it should work after May 2009. This means that we have little idea about what the predicted F10.7 flux should be. If the Sunspot Number prediction is correct, then the F10.7 flux is predicted too high, and if the F10.7 flux prediction is correct, then the predicted Sunspot Number is too high. My own feeling is that since the predicted Sunspot Number is really a prediction of the number of active [magnetic] regions which should be reflected in the F10.7 Flux, that the Sunspot Number [based on visible spots] will be much smaller than the predicted values. This will, indeed, be interesting to watch. Either way, we’ll learn a lot.

82 thoughts on “Why the SWPC F10.7 radio flux graph is wrong”

1. red432 says:

gotta ask: In “The Long Winter” by Laura Ingalls Wilder the old indian tells them that every seventh winter is a hard winter and the 3 hard winter (the 21st) is the hardest of all. Does this bit of folklore correlate with any solar or other cycles you guys chat about? (I’m a big fan of the Little House series — read them to 3 daughters…)

2. Is there any correlation between the radio flux and the solar wind?
That would be of high interest.

3. Carlos says:

OT: http://www.nytimes.com/2009/05/18/science/earth/18juneau.html?_r=1
Sorry. But. Is the North American plate post glacial rebound being accounted for in the sea level rise accounting? Blaming it on current glacial melt rather than simply a continuation of the overall Holocene melts seems way off track to me. Not surprising, though.
More on topic: Several years ago, the Max Planck Institute posted a release stating that Solar Activity was at or above a 1,000 year high. Is that high now gone (as I assume), what did they mean, exactly, and do you agree with their statement?

4. Mark Hugoson (19:10:35) :
Is there any correlation between the radio flux and the solar wind?
There is [and there isn’t]. Solar activity itself [including F10.7] has a causative influence on the solar wind [that’s the is part], but not every little wiggle on the F10.7 graph has a corresponding solar wind wiggle [that is the isn’t part].

5. jae says:

Leif: Thanks, again. It is so refreshing to read stuff from another genuine scientist who is out there trying to present the “best” info. available. Kudos, man!!!

6. Mike Lorrey says:

Very nice, concise post, Leif. I take it then that you expect the sunspot numbers to be on the low end. Have you done any sort of a plot of how low the cycle 24 max will be relative to how long it takes to get started?

7. Mike Lorrey says:

Oh btw, dad’s been following planting advice from some gardeners who are warmists, they all seem to have planted early this year. Problem is, tonite we are supposed to get a cold snap down to 20 F here in NH, which should kill off the warmists spring gardens nicely. But then again, thats weather, not climate….. rofl

8. a jones says:

Quaere
I know our main data on 10.7 goes back to 1947 but is there any organised regular data on this going further back? since I assume we should have been able to measure this for at least a decade before this.
Despite tantalising hints I have not been able to find any such records.
Kindest Regards

9. Fernando says:

well …. Leif is Leif.
But I get the feeling that minimum flow is 60.
I lost something

10. Ventana says:

Being above a 1,000 year high is hard
lol. That was a bit sloppy. 1,000 or more years, then.
I noticed that on page 4 of your second pdf, the “floor” seems to have much more variablity than your previous guest post indicates (where they were very much aligned). Is there any reason why, in your opinion, the floor 1000 years ago couldn’t have been even lower than it is currently, which seems now to be lower than the last two minima?

11. Mike Lorrey (20:06:57) :
Have you done any sort of a plot of how low the cycle 24 max will be relative to how long it takes to get started?
I think SC24 has started in earnest:
http://www.leif.org/research/TSI-SORCE-2008-now.png
a jones (20:15:01) :
I know our main data on 10.7 goes back to 1947 but is there any organised regular data on this going further back? since I assume we should have been able to measure this for at least a decade before this.
The radio emission was discovered during WWII but was secret until after the war, so there really isn’t any records.
Ventana (20:17:16) :
I noticed that on page 4 of your second pdf, the “floor” seems to have much more variablity than your previous guest post indicates (where they were very much aligned).
The ‘floor’ on page 4 pertains to the interplanetary magnetic field which is only peripherally related to F10.7. The floor in F10.7 cm [or the FUV flux] is shown on the Figure on page 7.
Is there any reason why, in your opinion, the floor 1000 years ago couldn’t have been even lower than it is currently, which seems now to be lower than the last two minima?
I assume you are now talking about the interplanetary magnetic field, B. Residual solar activity at the previous two minima kept that field a bit above the floor. At the current minimum solar activity has hit bottom as it last did in 1901 and 1913, and B is duly down to values that we infer for that time: http://www.leif.org/research/AGU%20Fall%202008%20SH24A-01.pdf
Since, you can’t less than no activity, we don’t think the floor can go much lower, but, in the end, that is speculative.

12. Mike Lorrey says:

Leif,
MF is at its lowest variation, how would 24 have started if this component has not taken off yet? We’re not seeing any increase in sunspot activity either.
Also, from the second paper you posted a link to, you state that Earth’s magnetic field has decreased 10%. What impact does this have on the amount of TSI that reaches Earth’s surface?

13. George M says:

Leif:
10.7 cm converts to about 2.8 GHz. I see on the frequency allocations chart that 2.69 to 2.7 GHz is allocated to Radio Astromomy, so maybe that is the actual frequency measured. The year of 1989 is within the time frame where the signal population in this portion of the radio spectrum began to expand greatly, including satellite borne transmitters. I wonder if the loss of correlation of the curves at the weak signal end could be due to an increase in the noise floor? The effect is certainly observable in other parts of the radio spectrum if you know what to look for, and might go unnoticed on a frequency where there are supposed to be no other signals. Also, why was that particular wavelength chosen in the first place? Is there a sun specific emission there, like the Hydrogen line near 610 MHz?

14. Mike Lorrey (20:51:42) :
MF is at its lowest variation, how would 24 have started if this component has not taken off yet? We’re not seeing any increase in sunspot activity either.
The solar Mean field [MF] basically measures the magnetic field strength of low-latitude coronal holes, and SC24 flux simply has not come down low enough yet for that to show up. We are seeing an increase in SC24 activity, even in the sunspot number [small as it has been – but that was the whole point of the previous essay, that perhaps there would be less visible spots]
Also, from the second paper you posted a link to, you state that Earth’s magnetic field has decreased 10%. What impact does this have on the amount of TSI that reaches Earth’s surface?
None
George M (20:53:56) :
I wonder if the loss of correlation of the curves at the weak signal end could be due to an increase in the noise floor?
If anything the noise [internal variation] has gone down. But the observers try to control and measure the noise, and AFAIK do not report any noticeable increase.
Also, why was that particular wavelength chosen in the first place? Is there a sun specific emission there, like the Hydrogen line near 610 MHz?
I think it has to do with availability of surplus radar equipment that Covington has to his disposal. Arthur Covington and his colleagues at the National Research Council in Ottawa used bits of military surplus radar and test equipment to make a radio telescope. The antenna was a 4ft (1.2m) paraboloid from a Type IIIC Gun Laying Radar, mounted on a prototype mount casting for a Model 268 radar. By leaning the mount so that the azimuth axis was pointed at the Pole Star, it was converted into a simple polar mount, which made tracking the Sun much easier. The receiver was a Dicke switching receiver used during the war to test silicon mixer crystals for radar applications. The radar system operated at a frequency of 2800MHz, which is a wavelength of 10.7cm.

15. partic says:

The really fascinating thing about now is how the Penn and Livingstone prediction is shaping up as cycle 24 picks up. There are Sun spots, probably, but we can’t see them. Why? Is this what was happening during the Maunder? Does it affect climate? How? After seeing the extraordinary economic collapse occur exactly the way the people I was reading 4 or 5 years ago predicted, I now have the (intellectual) good fortune to see a significant moment in Solar Science play out. Lief, your contribution here and at solarcycle24.com is greatly appreciated. Thank you and may your most cherished theories be falsified. (It is good for you as a scientist and a person, not that many in the blogosphere would agree)

16. Mike Lorrey (20:51:42) :
Also, from the second paper you posted a link to, you state that Earth’s magnetic field has decreased 10%. What impact does this have on the amount of TSI that reaches Earth’s surface?
Although my answer was ‘none’, there are some that claim that cosmic rays influence the albedo [although observations show otherwise], and since the cosmic ray flux should go up with decreasing magnetic field, one could surmise that more clouds would form and temperatures therefore drop [although clouds also have a positive greenhouse effect]. Temperatures have generally increased since 1860, so perhaps this effect is not so strong. I think that ‘none’ still is a good answer.
partic (21:31:19) :
I now have the (intellectual) good fortune to see a significant moment in Solar Science play out.
Yes, times are exciting…
But let’s not forget that all this is still just speculation [however well founded].

17. Leon Brozyna says:

Dr. Svalgaard,
It is a pleasure to read something that seems from another era, where rigorous precision of thought was valued. Such discipline as you’ve exhibited almost commands the reader (at least this reader) to think carefully upon the matter being read.
So, the assumption that was made in the new SWPC prediction is that the F10.7 & SSN will again agree as they did prior to 1989, even though there is no reason to assume this will happen.

18. pkatt says:

Hey, if that magnetic region near the equator of the sun spits out a spot… what cycle will it be from?

19. steptoe fan says:

well, IF something [ the sun ] did change around 1990, maybe the polynomial being used has to change to, it’s not the best fit anymore.
what would the coeffs look like for a 4th degree poly if it were generated by data starting in 1990 ? Why stop at a 4th degree ?
I have to go back and look at my numerical analysis book.
very interesting article, I also used your link and studied up on the hardware.

20. rbateman says:

Mike Lorrey (20:11:10) :
I call that being distracted by alarmist reports, and failing to pay attention to what thier history tells them. While the connection between solar activity and climate/weather is messy business, there is plenty of historical record to show that crop problem years are more abundant in low solar activity phases, such as we have spent the last couple of years in.
It is a good idea in such times to plant 2 varieties: One warm and one cooler.
You can use shade cloth for cooler varieties when it’s too warm, but you need a greenhouse for warmer varieties when frosts hit late.
It’s the outliers which kill the crops.

21. rbateman says:

If anything the noise [internal variation] has gone down. But the observers try to control and measure the noise, and AFAIK do not report any noticeable increase.
In other words, they are observing the background noise separately and calibrating it out. That would be good and sound scientific practice.

22. Telboy says:

Although a science ignoramus I appreciate what little I understand of what I have read on this thread, but more than that I admire the calm, intelligent way in which the discussion has progressed. I look forward to reading more.

23. Rik Gheysens says:

* “It is simply incorrect to start the curve from a flux of 60 and inexplicable [to my way of thinking – other than plain sloppiness] why the graph should disagree with the published table at http://www.swpc.noaa.gov/ftpdir/weekly/Predict.txt
Can we expect a correction of the SWPC Graph soon? It is indeed incomprehensible why the figure should disagree with their published table.
* On May 8 you wrote:
” from past relationships we know [if we use the correct ones] how much F10,7 to expect for a given SSN. The recommended [by the international Radio Communication people] formula is F10.7 = 63.7 + 0.728*SSN + 0.00089*SSN*SSN, that gives 65ish for the low numbers we have now and 136 for SSN=90.”
Is this formula the result of fitting the monthly average the F10.7 flux (reduced to 1 AU) against the International Sunspot number, R, for the interval 1989-2009? Or is it for the entire interval 1951-2009?
Thanks for clarification!

24. May be a dumb question – but how do we have 1000 year record of solar activity?

25. A possible problem that may surface during SC24 is the way we count sunspots these days compared to the past. Trying to match other solar output records may be skewed because of the sun speck counts not really showing the true picture.
The last time we saw the Sun as it is today is probably 200 years ago, so using our counting methods of the past 100 years may not be accurate when trying to compare with the last grand minimum. If we keep getting counts of 18 for specks like we have today, the SC24 tally will be meaningless.

26. Leif – when you state that ‘observations show otherwise’ with respect to the relation of cosmic rays to clouds, what published papers are you referring to?
Svensmark’s observations covered cycle 22 and showed a clear 3% change in cloud from peak to trough of the cosmic ray flux (which follows the solar cycle pretty closely); he found a similar pattern for cycle 23, though was criticised for using a different cloud data set. That is not to say the criticism nullified the findings – which the Danish Space Center still supports. Usoskin at the University of Oulu in Finland also found a correlation. There were reports in the BBC and New Scientist that a paper by Sloan and Wolfendale failed to find the correlation – but on inspection of that paper, the authors actually confirmed the relationship, but reckoned it could only account for 25% of the cloud changes – their paper was not published in the usual solar-terrestrial journals and hence was not subject to appropriate peer review with regard to their methods. So – as far as I can tell, the jury is still hung on this one.

27. rbateman says:

Geoff Sharp (04:00:55) :
A possible problem that may surface during SC24 is the way we count sunspots these days compared to the past

If L&P continues down it’s path, the current counting methods will quickly become acadmemic. These spots that are mere pinpoints are fine to count a 1 each in a group, but to give a 10 to them is nuts. Saturday’s spot actually had a penumbra, and deserves it’s count.
It’s embarassing to have Leif read my post Sunday morning of a string of pearls observation, then by the time I get to him to project them they are vanished.
Like Leif’s previous article, the SSN and the Flux derived SSN agreed well until it didn’t, and now we know something we didn’t know.
I’d say it’s a safe bet there are yet more surprises in store.

28. pkatt (00:29:00) :
Hey, if that magnetic region near the equator of the sun spits out a spot… what cycle will it be from?
Cycle 23
steptoe fan (01:07:06) :
what would the coeffs look like for a 4th degree poly if it were generated by data starting in 1990 ? Why stop at a 4th degree ?
Flux = 68.39 + 0.4093 R + 0.01172 R^2 – 0.00007867 R^3 + 0.00000013886 R^4
Stop at four, because further terms do no improve the fit.
Rik Gheysens (02:42:36) :
Can we expect a correction of the SWPC Graph soon? It is indeed incomprehensible why the figure should disagree with their published table.
I don’t think the graph will be corrected in the time while it is still wrong. After the end of the year no correction is needed anymore.
Is this formula the result of fitting the monthly average the F10.7 flux (reduced to 1 AU) against the International Sunspot number, R, for the interval 1989-2009? Or is it for the entire interval 1951-2009?
I’m not quite sure about the time frame used, but it certainly is for the whole time interval for which we had measurements at the time when the formula was derived.
May be a dumb question – but how do we have 1000 year record of solar activity?
We don’t, but solar activity modulates cosmic rays that in turn generate radioactive nuclei deposited in tree rings and ice cores. Calibrating those into sunspot numbers is a delicate business and there is great uncertainty in the numbers derived.
Geoff Sharp (04:00:55) :
If we keep getting counts of 18 for specks like we have today, the SC24 tally will be meaningless.
It will, but even more importantly the tally will be too high and the problem identified in the F10.7 data is that the sunspot tally since 1989 is too low.

29. Peter Taylor (04:43:14) :
when you state that ‘observations show otherwise’ with respect to the relation of cosmic rays to clouds, what published papers are you referring to?
I said that “claim that cosmic rays influence the albedo [although observations show otherwise],” that is the albedo not the clouds. Presumably the albedo is the measure of how much of TSI gets absorbed by the surface. The albedo is measured by observing Earthshine on the Moon. Here is a graph [Palle et al.] of the albedo the past two solar cycles: http://www.leif.org/research/albedo.png It is clear that there is no solar cycle signal in that data.

30. Ben Gallagher says:

“Although my answer was ‘none’, there are some that claim that cosmic rays influence the albedo [although observations show otherwise], and since the cosmic ray flux should go up with decreasing magnetic field, one could surmise that more clouds would form and temperatures therefore drop [although clouds also have a positive greenhouse effect]. Temperatures have generally increased since 1860, so perhaps this effect is not so strong. I think that ‘none’ still is a good answer.”
Svensmark’s theory (right or wrong I don’t know :)) is that the earth’s magnetic field would not have much impact due to it not being strong enough to deflect muons from reaching the lower atmosphere which is where he believes the increase in cloud occurs when GCRs hitting the Earth are high. In other words, the muon count in the lower atmosphere varies only a very small amount as a direct result of changes in the Earth’s magnetic field.

31. Leif,
Allthough the observed sun spot/speck count will be low in SC24, how will that effect
the F10.7 Flux. I understand it is not the the spot but the plage that does the
emmiting, and we will have plages even if the spot is not visable.
As a recent radio ham (retirement hobby) I need the F2 layer to be ionised to get
some decent DX (long distance and preferably rare or exotic locations) before I
pop my clogs.
How much Flux in SC24 ? and how will that effect Radio Communications ?

32. Enjoy all your informative essays (especially informative for me as a geologist and mining engineer). I realize that the “fit” decayed only after 1989, but given this departure from the fit, why wouldn’t one use this to predict a lower sunspot number curve for cycle 24? It is afterall only the next cycle and seems fair probability that it may take at least until the next cycle for F10.7cm and sunspot number correlation to snap back together.

33. Geoff Sharp:If we keep getting counts of 18 for specks like we have today, the SC24 tally will be meaningless.
This affirmation is simply heretic, and the evolution of events and history always confirms the heretics view.

34. MartinGAtkins says:

Leif Svalgaard (20:37:38) :

I think SC24 has started in earnest:
http://www.leif.org/research/TSI-SORCE-2008-now.png

You don’t have me fully convinced yet. The last area of activity produced a dead pixel and we have another active area just come into view. There seems nothing new showing on stereo behind. So my question is this, do active areas such as we are seeing, by their nature elevate TSI and 10.7 flux? If they prove to be transient and no more areas develop for a week or two should we expect to see TSI and flux wane. When the active areas are on the other side of the sun, will TSI and flux remain elevated.
It’s about time I thanked you for perseverance and amusingly droll attempts to educate us. I’m sure many WUWT readers have learned much and in doing so abandoned their first misguided assumptions about our star and are developing new ones. 🙂

35. Nic says:

I know there is an adjustment to the solar flux as reported, due to the earth’s varying distance from the sun during the year, but what is that adjustment, relative to the time of year please?

36. KEN (05:23:25) :
How much Flux in SC24 ? and how will that effect Radio Communications ?
The F10.7 flux is a proxy of the Ultraviolet flux [which is what is doing the ionizing, not the radio flux]. I think that the radio flux will be 120 sfu, and the ionosphere will not go away
Gary Pearse (05:45:13) :
why wouldn’t one use this to predict a lower sunspot number curve for cycle 24?
Because the breakdown of the relation has only now been realized and it takes a while to confirm and convince the scientific community about such a thing. Scientists are [rightly] extremely conservative when it comes to such radical ideas.
MartinGAtkins (06:05:47) :
do active areas such as we are seeing, by their nature elevate TSI and 10.7 flux?
Yes, with the added little twist that if a significant spot develops in the middle of the active region that dark spot decreases TSI. You can see the recent increases here:
http://www.leif.org/research/TSI-SORCE-2008-now.png
i>If they prove to be transient and no more areas develop for a week or two should we expect to see TSI and flux wane.
Yes, and perhaps more importantly the areas will rotate out of view, and:
When the active areas are on the other side of the sun, will TSI and flux remain elevated.
no longer elevate TSI and Flux.
Nic (07:03:33) :
but what is that adjustment, relative to the time of year
When we are closest to the Sun in January, the flux is 3.5% higher, and when we are farthest from the Sun in July, the flux is 3.5% lower. So, if we have a ‘real’ flux at 1 AU in July of 70, then we’ll only observe 70*(1-0.035) = 67.5 sfu.

37. Looking backwards. does this “adjustment” fix the 1989 difference between SSN and f10.7 radio flux?
“The progressive drift is much larger than the 3% correction and is therefore not due to the correction. It seems inescapable that the relation between the sunspot number and the microwave flux has changed significantly in recent years. Another way of showing this is Figure 12:”

Looking backwards. does this “adjustment” fix the 1989 difference between SSN and f10.7 radio flux?
“The progressive drift is much larger than the 3% correction and is therefore not due to the correction.

And, in fact, the correction is only half that, as it is made on only one half of the data [on one of the two series].

39. rbateman says:

Leif: The answer you gave in SolarCycle24.com made the best sense of any….
that the rise in activity does not have to be tied to sunspots. Faculae are active regions, and they have increased. So I do believe you are correct that SC24 has begun in earnest. It is somewhat spotless, however. Earlier, you had attested to there being a normally active Sun during the Maunder, again mostly spotless, but active nonetheless.

40. pkatt says:

I do try not to sound stupid, but I have to ask. If the active regions on the sun go straight from an area that could produce a sunspot to a degraded magnetic area or coronal hole, would they not still emit f10.7 radio flux?

41. Robert Wood says:

Interesting graphs, Leif. One can see the increase in 10.7m and TSI corresponding to the two large ex-CME Sun splats moving across the Sun over the past few days, but the MF is still moribund; Probably why major sunspots didn’t form from the regions from the CMEs ??

42. Leon Brozyna says:

@ Leif Svalgaard (07:55:27)
When we are closest to the Sun in January, the flux is 3.5% higher, and when we are farthest from the Sun in July, the flux is 3.5% lower. So, if we have a ‘real’ flux at 1 AU in July of 70, then we’ll only observe 70*(1-0.035) = 67.5 sfu.
So, we have the ‘real’ flux value and the observed flux value which are the same only when the Earth is at 1 AU in April & October. The rest of the time the observed flux value has to be adjusted by varying amounts up to ±3.5% (reached at apogee (July) and perigee(January)). This adjusted flus value then gives us a standardized frame of reference with which to study the sun.
My question(s) – what gives us the 3.5% adjustment at apogee & perigee? Upon what is the figure based? Is there a chart or a formula to determine each date’s adjustments for when we’re not at apogee or perigee?

43. Leon Brozyna:what gives us the 3.5% adjustment at apogee & perigee? Upon what is the figure based? Is there a chart or a formula to determine each date’s adjustments for when we’re not at apogee or perigee?
Why is it so that now 2+2=4.14? 🙂

44. Fluffy Clouds (Tim L) says:

Leif, if you will, 😉
can you give us an approximation based on the F10.7 flux prediction, what then the max Sunspot Number prediction would be?
No one will hold you to it lol.
Tx
If not in public then E-mail it to me 😉

45. Steven Kopits says:

Could we have a nice piece on solar cycles of various sorts and earth temps, covering what we know, what we don’t know, and what we hypothesize–in layman’s terms, please.

46. Leon Brozyna (10:25:01) :
My question(s) – what gives us the 3.5% adjustment at apogee & perigee?

The correct terms for an orbit around the Sun is Aphelion (farthest) and Perihelion (closest). The adjustments come from the varying Sun-Earth distance of a near elliptic Earth orbit. Such adjustments to 1AU apply for every point in the orbit, not just at Aphelion and Perihelion.

47. road trip planner (03:17:06) :
May be a dumb question – but how do we have 1000 year record of solar activity?
Not at all. According to this hieroglyph even ancient Egyptians were into Sunspot numbers. Note a pock-marked Sun. Was the Sphinx holding peace of a coloured glass (known about since Phoenician times 1600 BC), and taking notes on the clay tablets. You may not instantly agree, but a glass of good vine might help.
http://www.uned.es/geo-1-historia-antigua-universal/EGIPTO%20RELIGION/akh_worship_a_page2-1_05.jpg

48. Fluffy Clouds (Tim L) says:

look s to be a factor of 0.01925 per day if 7.000% is correct .

49. Walter Dnes says:

A suggestion… according to you, and Livingston & Penn, sunspots are decreasing anamalously versus 10.7 cm flux. Have you considered changing your SC24 prediction from sunspot counts to 10.7 cm flux values? This would give an apples-to-apples comparison with past cycles.

50. Correction-
Should be: piece and wine.
Must stop using auto spell correction.

51. I understand overestimation of temperatures to support AGW, but why inflate the sunspot number?

52. George E. Smith says:

Given the state of electronics in 1947, let alone 1937, I doubt that there was a whole lot of 10.7 cm solar emissions being regularly monitored back then; possibly detected; but I doubt there was significant measurment capability at nearly 3GHz.
And yes I was there; so I oughta know.
George

53. Leon Brozyna (10:25:01) :
what gives us the 3.5% adjustment at apogee & perigee? Upon what is the figure based? Is there a chart or a formula to determine each date’s adjustments for when we’re not at apogee or perigee?
The Earth’s orbit is an ellipse with a the largest difference 1/60 times larger than average and the smallest distance 1/60 times smaller than average, for a total of 1/60 +1/60 = 1/30. Because the flux falls off with the square of the distance, the flux difference is twice the distance difference, or 1/15 or the 7% total. A simple sine wave with maximum on January 4th and minimum on July 4th is a good fit to the every day distance.
Fluffy Clouds (Tim L) (12:39:30) :
can you give us an approximation based on the F10.7 flux prediction, what then the max Sunspot Number prediction would be?
No one will hold you to it lol.

Based on the polar fields and the ‘standard’ sunspot number the predicted SSN max is 70 [as of today]. If L&P are correct, no one knows. But what I predict is not really sunspots, but magnetic regions and they may still be there, a total of 7 per day at maximum. You get this number by dividing the SSN by 12.
George E. Smith (14:48:54) :
Given the state of electronics in 1947, let alone 1937, I doubt that there was a whole lot of 10.7 cm solar emissions being regularly monitored back then
Arthur Covington succeeded in monitoring the 10.7 cm flux from April 1947 on.

54. rbateman says:

Carsten Arnholm, Norway (12:31:03) :
I don’t think they were actually looking for them per se, but were looking for transits of the moon, Mercury, Venus, etc. in the early times.
This site has current sightings: http://www.vds-sonne.de/gem/res/results.html
The last one was late March 2008 : http://www.vds-sonne.de/gem/res/anetz/J2008.html
The very biggest naked-eye spots (from my readings IMHO) occur just as the cycle nears end. The ones where you cannot help but notice, the monster spots. Something about the 2 hemisphere’s magnetics or spots coalescing.

55. So, can we get an hour’s worth of “Solar Science 202” credit for attending Lief’s classes regularly, and apply that to our required professional training hours for the year?
More importantly, can HE get 1200 students’ worth of tuition fees for THEIR attendance of HIS on-line lectures for “Solar Science 202” ? 8<)

To those who question whether the "eyeball only" observations in the Middle Ages would skip or miss small spots, I would point out that – as the months went by with fewer and spots, with longer intervals between spots that had previously (hundreds of years!) been regularly occurring – the observors would be both looking intensely FOR small spots, and would be more and more attracted to record even hints of spots. Over the years through the Minimum, absence of the their goal (seeing and counting spots) would mean even closer scrutiny of the sun every day that clouds did not cover its surface.
Also, closer attention to the sun through the minimum (as the absence continued) would mean that more observers over different areas of the Continent would be looking up every day – so even if several observers were covered by clouds, somebody else would be more likely to be looking up that day and could verify that no spots were visible.

But I do wish Hathaway would show not only his latest (very misleading!) prediction curve for SC24 and SC25, but each of his previous (very wrong!) predictions as well.

56. rbateman says:

1705842 -42 MAY 5 / JUN 3 (YUNG-KUANG/1/4/-) CHINA
“THE SUN WAS WHITISH BLUE IN COLOR AND CAST NO SHADOWS. RIGHT AT ITS
CENTRE, THERE WERE FREQUENTLY SHADOWS AND NO BRILLIANCE. THAT SUMMER
WAS COLD UNTIL THE 9TH MONTH, WHEN THE SUN REGAINED ITS BRILLIANCE”.
[“HAN SHU”; YAU & STEPHENSON (1988)/2]
Now that’s what I call a highly unusual observation.
I haven’t yet finished reading through them all for color color changes, but a reddish sun is the normal color change reported.

57. a jones says:

By the mid 1930’s both the Marconi and EMI companies had receivers capable of working in these bands, as did their German rivals, the problem was transmitting pulses of sufficient energy to be useful. Hence the blocking oscillator and the dual beam tetrode and all that: until the cavity magnetron of course.
Which suggests they could have easily detected and measured on 10.7 if they had wanted to and if they had known what the noise was that they noticed and thus, as it were, why they might want to. One assumes that they simply regarded the noise as a nuisance rather than a possibly useful scientific observation: although I may do them an injustice.
As to the Maunder minimum far from becoming ever more eager to spot sunspots their absence increasingly led to the sceptical idea amongst the new generation of astronomers that they did not really exist at all: so that the later generation which grew up when they were exceedingly rare far from keenly searching for them tended to regard them, no pun intended, as almost if not quite mythical, and an eccentric obsession of their forebears. Only when they reappeared in quantity, as it were, did they reluctantly decide they were real after all.
Kindest Regards

58. John F. Hultquist says:

Robert A Cook PE (18:00:30) :
“So, can we get an hour’s worth of “Solar Science 202″ credit. . .”
I’ve been lurking in the back of the classroom switching back and forth between links, searches, charts – and trying to do everything else I need to do. Scrambling to keep up, describes it well. Enjoying it all. Thanks to Leif and all the rest of you. John

59. rbateman says:

As to interest and coverage prior and during the Maunder:
From ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SUNSPOT_NUMBERS/GROUP_SUNSPOT_NUMBERS/list1.dat
1642 1684 4186 HEVELIUS, J., DANZIG
and in this list : ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SUNSPOT_NUMBERS/GROUP_SUNSPOT_NUMBERS/alldata
Hevelius observed sunspot groups from 1642 to 1684, a total of 42 years, starting before the onset of the Maunder.
Likewise, 1660 1682 3697 PICARD, J., PARIS put in 22 years followed by
1682 1718 7170 LA HIRE, PH., PARIS
ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SUNSPOT_NUMBERS/GROUP_SUNSPOT_NUMBERS/invent.dat
One can see who was keeping the sun under constant surveillance in what year.
There were enough dedicated observers.

60. Robert A Cook PE (18:00:30) :
More importantly, can HE get 1200 students’ worth of tuition fees for THEIR attendance of HIS on-line lectures for “Solar Science 202″ ? 8<)
There is always that shameless “donate” button… on my website…

61. rbateman (21:43:15) :
One can see who was keeping the sun under constant surveillance in what year….There were enough dedicated observers.
But one has to be a bit suspicious of claims that they observed every single day for years on end. The weather in Northern Europe is simply no good enough for that [not even California]. Here are the claimed days of observations for Hevelius:
1648 366 HEVELIUS, J., DANZIG
1649 365 HEVELIUS, J., DANZIG
1650 365 HEVELIUS, J., DANZIG
1651 365 HEVELIUS, J., DANZIG
Even Ken Schatten agrees with me that these numbers are inflated. One way of getting a perfect record of 365 days is for the observer to note: “last year I didn’t see a single spot”. Hoyt interpreted that [wrongly] as 365 days of clear weather with observation on every single day, even the Sabbath…

62. rbateman says:

One always has to be a bit suspicious.
Hevelius did fall off in his later years, therefore we have to rely on others to fill in the gaps.
It would take several dedicated observers in Europe to get good coverage.
We need more digitization of existing drawings from the period, and since this is really an important time, all the more reason.
(The curiosity is killing me !).
btw…I tried the shameless donate button too, but it didn’t work for me, so off it went to the trash bin. An entrepenuer I am not.
The luck of the Irish.

63. Mike Lorrey says:

” Leif Svalgaard (05:07:49) :
I said that “claim that cosmic rays influence the albedo [although observations show otherwise],” that is the albedo not the clouds. Presumably the albedo is the measure of how much of TSI gets absorbed by the surface. The albedo is measured by observing Earthshine on the Moon. Here is a graph [Palle et al.] of the albedo the past two solar cycles: http://www.leif.org/research/albedo.png It is clear that there is no solar cycle signal in that data.”
I wouldnt say that, sc 22 ended in 1996-97, and if you add in the Palle data since 2000, it is clear that the albedo is following the 22 year magnetic solar cycle.

64. Alex says:

So, yesterday SC24.com said that sunspot 1007 has faded and today (20/05) it is written:
“Sunspot 1007 has faded and is now simply a magnetic plage region once again. It did fetch a sunspot number of 11 however.”
How is that possible? A classic plage has no spots!
On the SC24 discussion board, someone asked:
“Isvalgaard I’m going to beat this DEAD HORSE one last time. Would a spot like 1017 have been counted during the cycle 23 peak ( and given a count of 18) yes/no.
Leif replied:
“Yes, but probably not during the 13 cycle peak, and VERY CERTAINLY not any before before 1893, because Rudolf Wolf [the inventor of the sunspot number] explicitly said NOT to count little specks and pores. His assistant, Alfred Wolfer, disagreed, so when Wolf died in 1893, guess what: the counting of specs began. Wolfer tried to put the [now larger] count back on the Wolf scale by multiplying the count by 0.6”
Did Rudolf Wolf request this at solar minimum too?

65. rbateman (21:43:15) :
One can see who was keeping the sun under constant surveillance in what year….There were enough dedicated observers.
Here is number of the observation days recorded by Paris Observatory in each month for years 1666-1668.
Note: an unusually low numbers in 1666. 1668 and the following years appear to be close to what could be expected.
1666:1,0,1,1,4,4,0,2,3,12,13,9
1667:8,11,8,5,14,8,15,18,12,5
1668:6,8,11,11,13,16,12,14,15,11,10,10

66. rbateman (21:43:15) :
One can see who was keeping the sun under constant surveillance in what year….There were enough dedicated observers.
Here is number of the observation days recorded by Paris Observatory in each month for years 1666-1668.
Note: an unusually low numbers in 1666. 1668 and the following years appear to be close to what could be expected.
1666:1,0,1,1,4,4,0,2,3,12,13,9
1667:9,8,11,8,5,14,8,15,18,9,12,5
1668:6,8,11,11,13,16,12,14,15,11,10,10

67. Mike Lorrey (23:24:03) :
I wouldnt say that, sc 22 ended in 1996-97, and if you add in the Palle data since 2000, it is clear that the albedo is following the 22 year magnetic solar cycle.
Except that the cosmic rays follow the 11-year cycle and the albedo should follow the same 11-year cycle if the variation of cosmic rays is the reason for the changing albedo [and hence temperature].

68. Alex (23:28:18) :
Did Rudolf Wolf request this at solar minimum too?
At all times.

69. Leif Svalgaard (06:47:47) :
Except that the cosmic rays follow the 11-year cycle and the albedo should follow the same 11-year cycle if the variation of cosmic rays is the reason for the changing albedo [and hence temperature].

Could it be one reason, if not the reason? Or even the primary reason?

70. Jeff Alberts (08:13:42) :
Could it be one reason, if not the reason? Or even the primary reason?
Either you have a definite theory, or you are just fishing around.

71. rbateman says:

The counting of sunspots has increased over time because of technology. If you have attempted to project them with modest equipment (like Wolf used), then you would know how tenuous the tiny spots really are.
So, there are really two issues at play inflating the value of observed sunspots:
1.) detection of miniscule areas (nearing pores in size)
2.) detection of nebulous spots
Solution: Multiply hemispherical area x contrast AND set a value where photographic spots = projected spots.
i.e. = in the future when we can detect sunspots down to .001 in value, it will still be .001 of a spot.

72. rbateman says:

How about turning the spot visibility on it’s ear?
When did 1017 disappear?
I am inclined to say it faded into statistical limbo Sunday, May 17th, and from there became increasingly irrelevant.

73. Mike Lorrey says:

Mike Lorrey (23:24:03) :
I wouldnt say that, sc 22 ended in 1996-97, and if you add in the Palle data since 2000, it is clear that the albedo is following the 22 year magnetic solar cycle.
” Leif Svalgaard (06:47:47) :
Except that the cosmic rays follow the 11-year cycle and the albedo should follow the same 11-year cycle if the variation of cosmic rays is the reason for the changing albedo [and hence temperature].”
I understand that, Leif. Try to think of a way that albedo could follow the 22 year cycle while cosmic rays follow the 11 year cycle. For instance, there is already a lot of dust and aerosols in the northern hemisphere to seed cloud formation, so the northern hemisphere, while the southern hemisphere does not. The southern hemisphere has a bigger ozone hole, etc.
There are a lot of differences between the northern and southern hemispheres which could cause cosmic rays to have different influence which could vary as the earth’s magnetic field interacts with the 22 year solar magnetic field cycle.

74. Mike Lorrey (11:48:36) :
I understand that, Leif. Try to think of a way that albedo could follow the 22 year cycle while cosmic rays follow the 11 year cycle.
First of all, we don’t have a 22-year cycle in albedo, we have a failure of an 11-yr cycle which you interpret as a 22-year cycle. Second, people that claim the solar cycle dependence [like Svensmark himself] claim that there is an 11-yr cycle, so, what I was saying was that there is no evidence for an 11-yr cycle in albedo to support the 11-yr cycle in temperature claimed by Svensmark to be the result of an 11-yr cycle in cosmic rays.

75. Mike Lorrey says:

Thanks Vukevic, the second link tells the tale: there is a 12 hour delay in north vs south anisotropy in the cosmic rays hitting earth. This means that one hemisphere would see its cosmic ray cloud formation happen during the day, and the other would see it happen during the night. Obviously daylight cloud formation would increase albedo and thus cool the planet, while night time cloud formation would have no effect on albedo and would boost warming. This is the smoking gun, IMHO, that explains everything.

76. Mike Lorrey says:

While each hemisphere has an equal amount of planetary area in day and night (obviously) the distribution of ocean and land being unequal is the issue.

77. Mike Lorrey (15:59:02) :
This is the smoking gun, IMHO, that explains everything.
You have to VERY humble now. First, the anisotropy is of the order of 0.05% or 1/2000, so for each 2000 cosmic rays in one hemisphere there are 2001 in the other, not much smoke. And the anisotropy is an sidereal day effect, not solar day. Sidereal noon drifts through all hours of the solar day through the year [4 minutes each day], so no day-night effect.
But I guess for a true believe such little details don’t matter 🙂