Counting Sunspots and Sunspot Inflation

Guest post by Dr. Leif Svalgaard

The official sunspot number is issued by SIDC in Brussels http://sidc.be/sunspot-data/ . The [relative] sunspot number was introduced by Rudolf Wolf http://en.wikipedia.org/wiki/Rudolf_Wolf  in the middle of the 19th century. He called it the ‘relative’ number because it is rather like an index instead of the actual number of spots on the Sun. Spots occur in groups [which we today call ‘active regions’] and Wolf realized that the birth of a new group was a much more significant event than the emergence of just a single new spot within a group, so he designed his index, R, [for any given day] to be a weighted sum of the number of spots, S, and the number of groups, G, giving the groups a weight of 10: R = S + 10*G. The number of 10 was chosen because on average a group contains about 10 spots, and also because it is a convenient number to multiply by.

clip_image002

Figure 1. a) Wolf’s standard telescope used before 1863. b) Still exists and used to this day. c) Wolf’s small, portable telescope that he used after 1863. Still exists and used to this day.

Later, Wolf introduced the so-called ‘k-factor’ to compensate for differences in the size of telescope, precise counting method, observer acuity, etc, in order to bring the relative sunspot number determined by another observer on to the same scale as Wolf’s: R = k (10*G + S), where k is 1 for Wolf himself using his ‘standard telescope’ [Figure 1a,b] and his rules [not counting the smallest spots] for counting spots. From the 1860s Wolf had to travel extensively and he used exclusively [for the rest of his life] a much smaller telescope [Figure 1c]. With a smaller telescope Wolf, obviously’ saw fewer spots [and groups!], so he used k = 1.5 to convert his counts to the scale of the standard telescope.

Wolf’s successor, Alfred Wolfer, thought [rightfully] that the rule of ‘not counting the smallest spots’ was too vague and advocated to count all spots and groups that could be seen. This, of course, made his count larger than Wolf’s, so based on overlapping counts during 1876-1893, determined that to place his [Wolfer’s] relative number on to the Wolf scale he should multiply by 0.6 [one could say that his k-factor was 0.6]. This conversion factor of 0.6 has been adopted by all [Zurich] observers ever since. Adopted, not measured, as Wolf is not around any more. SIDC adopts that same factor, thus striving to stay on the Zurich scale.

So far, so good. But at some point in the 1940s, the Zurich observers began to ‘weight’ sunspots according to size and complexity, such that large spots would not be counted just once [as Wolf and Wolfer did], but up to five times, i.e. given a weight of five. There is nothing wrong with that, if one then also adjusts the k-factor to reflect this new way of counting. The director of the Zurich observatory from 1945-1979, Max Waldmeier, may have thought [?] that the weighting was introduced a long time ago [he mentions ‘about 1882’] so that no change of k-factor would be needed. Waldmeier set up a station in Locarno in southern Switzerland [as the weather on the other side of the Alps is often complimentary to that in Zurich] to provide observations when it was cloudy in Zurich. The observers in Locarno [Sergio Cortesi began in 1957 and is still at it] were instructed to use the same weighting scale as Waldmeier in Zurich. Because SIDC to this day normalize all observations they collect from a network of 60-70 observers to the count from Locarno, the weighting scheme carries over unchanged to the modern sunspot number.

We know that Wolfer did not weight the spots [contrary to Waldmeier’s assertion], because Wolfer himself explicitly [in 1907] stated that each ‘spot is counted only once, regardless of size’, and also because Wolfer’s counts as late as in 1924 when compared to other observers’ simply show that single spots are counted only once no matter how large.

To get a feeling for how the weighting works, try to count the spots on the Locarno drawing for today http://www.specola.ch/drawings/2013/loc-d20130104.JPG and compare your counts with the values given for each numbered group in the little table at the upper right.

loc-d20130104[1]

(Note: I did this exercise, and found that my layman’s count was much lower than the “official” count, lending credence to Leif’s premise. Try it! – Anthony)

Marco Cagnotti’s [from Locarno] count is 11 groups and 53 ‘weighted’ spots. My count of the actual number of spots is 23. Try it for yourself. Your count may differ by about one from mine, but that does not change the fact that the weighted relative number 10*11+53=163 is about 23% larger than the ‘raw’, simple count of 10*11+23=133 that Wolfer and Wolf would have reported. For the whole of 2012 the ‘over count’ was 18%. So, it seems that the relative sunspot number suffered a 20% inflation because Waldmeier did not change his k-factor to compensate for the weighting.

Can we verify any of this? Well, one verification you can do yourself: just count the spots. But a better test is to ask the Locarno observers to report two numbers: the weighted count as usual and the unweighted count, where each spot is counted just once. Such a test has been [as is being] done. Figure 2 shows the effect of the weighting. Blue symbols show the official weighted count, and red symbols show Marco and my raw counts. The conclusion should be obvious.

clip_image004

Figure 2. Comparison between the official Locarno weighted count of sunspot [blue symbols] and the raw count of spots singly my myself and by Marco Cagnotti [director of Locarno observatory]

Can we check when the inflation actually began? At the Royal Greenwich Observatory photographs of the Sun have been taken ‘every’ day since 1874 until they stopped in 1975. From these photographs the RGO determined the area of all sunspots for every day. It turns out that there is a very good relationship [as you might expect – more spots, more area covered with spots] between the sunspot area SA and the sunspot number R. For the interval before Waldmeier that relationship is closely described by R = 0.3244 * SA^0.732 [for monthly values].

The top panel of Figure 3 shows how well the sunspot number calculated from this formula matches that reporter by the Zurich observers.

clip_image006

Figure 3. The effect of the 20% inflation of the Zurich sunspot number (Rz blue) compared with that one would expect from the sunspot areas (Rc red).

Applying the same formula to data after 1945 gives us the lower panel. Under the assumption that the Sun did not know about Waldmeier we would expect the same relationship to hold, but in fact there is an abrupt change of the observed vs. the expected sunspot numbers between 1946 and 1947 of [you guessed it] 20%. Several other solar indicators give the same result. So there are several smoking guns.

What to do about this? One obvious thing would be to simply to remove the inflation [dividing the modern sunspot number by 1.20] and to stop weighting the spots. This turns out to be a bad idea, at least users of the sunspot numbers complain that they do not want to change the modern numbers as they are used in operational programs. The next-best thing is to adjust the old numbers before 1947 by multiplying them by 1.20. This is what we have decided to do [at least for now]. Who are ‘we’? You can see that here http://ssnworkshop.wikia.com/wiki/Home

There is a precedent for this [with the same ‘solution’]. In 1861 Wolf had published his first list of relative sunspot numbers, which he then updated every year after that. But about 1875 he realized that he had underestimated Schwabe’s counts [which formed the backbone of the list before Wolf’s own observations began in 1849]. Consequently, Wolf increased wholesale all the published sunspot numbers before 1849 by 25%. So we are in good company.

A somewhat disturbing [to many people] consequence of the correction of the official sunspot number is that there is now no evidence for a Modern Grand Maximum [‘the largest in 8000 years’ or some such].

NOTE: Figure 4 added 1/5/13 at Leif’s request

Figure 4. (Left) The idea of the Modern Grand Maximum, MGM. (Right) The corrected Wolf Sunspot Number does not support a MGM

Figure 4. (Left) The idea of the Modern Grand Maximum, MGM. (Right) The corrected Wolf Sunspot Number does not support a MGM

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Thanks, Leif. And a Happy New Year to you!

tobyglyn

An informing and interesting post, thank you Leif and Anthony!

A somewhat disturbing [to many people] consequence of the correction of the official sunspot number is that there is now no evidence for a Modern Grand Maximum [‘the largest in 8000 years’ or some such].

I suspect that you mean “no evidence in the adjusted sunspot counts.” There are other lines of evidence, including beryllium-10 as a proxy (which is actually a proxy for galactic cosmic rays, themselves an implied proxy (as a reciprical) for solar wind which has been connected with sunspots.
While the connection to sunspots directly from this measure is tenuous, Be-10 is a more direct proxy for solar output in general, and this seems to correspond reasonably well to other measurements including the old-style sunspot measurements.
Independent of sunspots, the sun seems to vary over time, was high recently, and is dropping now — something you noted yourself on the last page of your report.
As you said: “Exciting times!”
===|==============/ Keith DeHavelle

Doug Huffman

Thanks, Dr. Leif, this is timely, as i wait the December SSN and its effect on the Smoothed Monthly Values. I’ve read a good bit of your papers site, and understood somewhat less. We live in interesting times.

cui bono

Nice. At least the time series hasn’t been *deliberately* distorted, unlike some we could all mention.
PS: Either need a bigger screen or new glasses – only counted 17.

flea rider

but would it be fair to say we are going into a minimum ??

Doug Huffman

As I understand it, Solar Maximum is defined when the Northern and Southern solar hemispheres’ magnetic fields reach a minimum and reverse polarity. They’re close but SC-24 maximum still approaches.

I was fine up to and including the 1+1 = 2 part… after that I kinda lost the thread and it got a little vague — maybe if I re-read… 😉

Doug Huffman

The graphic is in this file http://www.leif.org/research/AGU%20Fall%202012%20SH12A-07.ppt
Slide number 3

Thank you Dr. Svalgaard. I’m sure the pure minded are upset. As long as things are on the same relative base and no one is trying to calculate some absolute value, it makes little real difference. The danger, always present, is people will run off making assumptions that are not founded in facts but suppositions.

mpainter

A worthwhile posting; should help to clear up some of the confusion seen on WUWT

Big D in TX

“A somewhat disturbing [to many people] consequence of the correction of the official sunspot number is that there is now no evidence for a Modern Grand Maximum [‘the largest in 8000 years’ or some such].”
What does that mean?
Rather, what are the implications of that statement? (The consequences of not having had a Modern Grand Maximum.)
I am aware I may be showing some ignorance here; humor me, please.

fred

But isn’t all of this a bit simplistic? It assumes that 10 is the appropriate correction factor at minimum and maximum, and in active and inactive solar cycles, and in cycles with a Livingston and Penn effect and those without. Why not just count the visible spots above a certain size and call it a day.

Why is it that every single data series has to be tampered with? How the hell can you expect to get a fair comparison of past events to current events if you “adjust” the record? Oh, wait …

Keith DeHavelle says:
January 4, 2013 at 3:07 pm
Be-10 is a more direct proxy for solar output in general
No, 10Be depends on the geomagnetic field [the biggest factor], climate [the next biggest], and finally solar activity.
fred says:
January 4, 2013 at 4:03 pm
Why not just count the visible spots above a certain size and call it a day.
That is what we suggest. That ‘certain size’ being zero.
markstoval says:
January 4, 2013 at 4:08 pm
Why is it that every single data series has to be tampered with?
Why is it that some people cannot follow a straightforward demonstration?

Steve from Rockwood

Great/interesting post.

MattS

@markstoval,
Except that in the case of the sunspot numbers you don’t have a continuous string of consistent observations. Observations in different time periods were done use different methods and the variance in this case is a process not a technology issue. It is therefore impossible to make a valid comparison between current and past observations without adjusting one or the other.
This can be a problem in the land surface temperature records as well, but it the case of temperature it is minor vs all the other problems.

mobihci

why on earth would someone say-
“A somewhat disturbing [to many people] consequence of the correction of the official sunspot number is that there is now no evidence for a Modern Grand Maximum [‘the largest in 8000 years’ or some such].”
that makes no sense at all. first if you add both those charts together, you see no difference than the ‘uncorrected’ figures, it still peaks around 19 and 21 and 22 are higher than earlier years. ie it is still on the rise until the great crash of 23/24. its obvious even in the butterfly diagram-
http://en.wikipedia.org/wiki/File:Sunspot-bfly.gif
the beryllium proxy also backs up the recent high conditions.

herkimer

Leif
In an earlier track you provided the decadal average sunspot numbers for the new derived sunspot numbers for the period 1830 to1940. Is there a source for the derived annual figures? Also to what extent have these new numbers been accepted by all of your colleagues?

No, 10Be depends on the geomagnetic field [the biggest factor], climate [the next biggest], and finally solar activity. (emphasis added)

Just to confirm explicitly what you are implying in your response: When you wrote “there is now no evidence for a Modern Grand Maximum” you are now correcting this to note that there is indeed some evidence for this solar maximum outside of sunspots.
It seems to me that you are overstating the case even so, with regard to sunspots. Using your corrected numbers, sunspot activity for the last half of the 20th century is visibly higher than the prior half, and 20C values higher than earlier centuries. That the sunspot activity might vary somewhat less than thought does not mean that it is not varying significantly, agreed?
The math isn’t hairy
And logic’s not scary
But here I would parry
The numbers still vary
The new count of spot
Might be less than thought
But if they’re more hot
Then what have you got?
===|==============/ Keith DeHavelle

Willis Eschenbach

Leif, as always, most informative. My thanks.
w.

TomRude

Ach, Waldmeier… Perhaps, after Wolf and Wolfer, had they chosen a guy named “Wolfest” to the post we would have been spared this apotheticary accounting!
Yet on Figure 3, discarding the infamous blue curve and only using the virtuous red curve (Rc), we still end up with the top of 1935-1944 and 1955-1964 solar cycles spot count culminating over all others. Furthermore, all solar cycles post 1945, except the 1970 centered one -and so far cycle 24-, still exhibit more 100 counts than their pre-1945 ancestors.
Is this spurious or the reality?

When I started reading, I was afraid that I was going to discover yet another series that has been deliberately distorted. Fortunately, here, people still seems to be looking for the truth and not busy hiding it.

MattS says:
January 4, 2013 at 4:34 pm
It is therefore impossible to make a valid comparison between current and past observations without adjusting one or the other.
Wolf himself discovered [and actually used] how to make a valid comparison. Perhaps a topic for a future post, but here is the basic idea:
http://www.leif.org/research/Geomagnetic%20Calibration%20of%20Sunspot%20Numbers.pdf
mobihci says:
January 4, 2013 at 4:36 pm
it still peaks around 19 and 21 and 22 are higher than earlier years. ie it is still on the rise until the great crash of 23/24. its obvious even in the butterfly diagram-
Indeed some cycles are higher than others. The point is that there are high cycles in every century and no long-term trend the past 300 years.
herkimer says:
January 4, 2013 at 4:37 pm
derived annual figures? Also to what extent have these new numbers been accepted by all of your colleagues?
The simplest is to multiply all sunspot numbers [which you can ghet from SIDC] by 1.2 before 1947.
There is no doubt about the discontinuity arounbd 1946. And the remedy for it. There can be [and is] debate as to how good the numbers [even after correction] are for the early part of the series, e.g. before 1825. This issue is the topic for the next two workshops scheduled for later this year.
Keith DeHavelle says:
January 4, 2013 at 5:01 pm
Just to confirm explicitly what you are implying in your response: When you wrote “there is now no evidence for a Modern Grand Maximum” you are now correcting this to note that there is indeed some evidence for this solar maximum outside of sunspots.
No, that is not what I meant.
Using your corrected numbers, sunspot activity for the last half of the 20th century is visibly higher than the prior half, and 20C values higher than earlier centuries.
Indeed some cycles are bigger than others. The point is there are high cycles in every century. Some 20C cycles are high, but do not qualify as a ‘Grand Maximum’. Now, one can debate the semantics of ‘Grand Maximum’. What is usually meant can be seen in slides 4-7 of http://www.leif.org/research/The%20long-term%20variation%20of%20solar%20activity.pdf

Ian H

Leif is a true scientist. He doesn’t make extravagant claims about things he doesn’t know. He makes conservative statements about things he is sure about. He openly states the limits of his knowledge, and if challenged can explain absolutely everything he does in as much detail as his audience can comprehend. He never appeals to authority or talks down to people. He doesn’t need to do that. He just knows more about sunspots than just about anyone else in the world. That what a scientist should be like and indeed what most scientists are like.
As Leif notes some here would find a grand solar maximum convenient as is would help to provide an alternative explanation for the late 20th century temperature increase. Nevertheless Leif can come here and argue with those who disagree with him and wipe the floor with anyone who chooses to challenge him on his subject, the sunspot record. This is what a scientist should be.
Could you imagine Mann trying to defend his hockey stick here? He’d get his head handed to him.

TomRude says:
January 4, 2013 at 5:07 pm
Is this spurious or the reality?
The red curve [upper right] on slide 7 of
http://www.leif.org/research/The%20long-term%20variation%20of%20solar%20activity.pdf
shows the series since 1700. The 20th century does not any longer qualify as a ‘Grand Maximum’
[at least I would not call it that, perhaps you would cling to the notion that it is?].

Justthinkin

Big D in TX says:
January 4, 2013 at 4:02 pm
“A somewhat disturbing [to many people] consequence of the correction of the official sunspot number is that there is now no evidence for a Modern Grand Maximum [‘the largest in 8000 years’ or some such].”
What does that mean?
Rather, what are the implications of that statement? (The consequences of not having had a Modern Grand Maximum.)
I am aware I may be showing some ignorance here; humor me, please.
No need to worry ,Big D. That’s what a lot of us guys/gals come here for…..to learn. You can teach to ignorance ,stupidity is terminal.
And BTW…..had the same myself….you just beat me to it :):)

TomRude

Since Wolf started his observation in the middle of the 19 century and that “At the Royal Greenwich Observatory photographs of the Sun have been taken ‘every’ day since 1874 until they stopped in 1975. From these photographs the RGO determined the area of all sunspots for every day”, we are only talking about 25 years of observation –roughly two solar cycles- at most that are litigious, i.e. without any other objective source of information such as photographs than Wolf’s. Would it be so difficult to recount the data once for all, introduce an uncertainty factor for the earliest two cycles observed by Wolf and, publish two reference datasets: the raw count and with today’s benefit of understanding solar physics and processes, offer an acceptable weighting for clusters versus spots if need be in a second dataset?
Also, in one comment, the author writes “Indeed some cycles are higher than others. The point is that there are high cycles in every century and no long-term trend the past 300 years”… Since sun spot counts was introduced by Wolf “in the middle of the 19th century”, it will only be 200 years of sun spot counting by 2050. What other dataset is used for the remaining 100 years of so of this trend, or absence of thereof?

RoyFOMR

IanH
‘Leif is a true scientist. He doesn’t make extravagant claims about things he doesn’t know. He makes conservative statements about things he is sure about. He openly states the limits of his knowledge, and if challenged can explain absolutely everything he does in as much detail as his audience can comprehend. He never appeals to authority or talks down to people. He doesn’t need to do that. He just knows more about sunspots than just about anyone else in the world. That what a scientist should be like and indeed what most scientists are like. ‘
+10 (on a scale of 1 to 10)

PJF

Why is it that every single data series has to be tampered with?
Perhaps it’s worth remembering that our host, Anthony Watts, is involved in a project that may “tamper” with a data series. His assessment of the changing standards of weather surface stations with time (I hope that’s a close description) might result in a re-examination and adjustment of the temperature record towards accuracy.
This is generally regarded around these parts as a good thing. Yet some dismiss Dr Svalgaard’s project as “sunspot fiddling”. Very unfair and not conducive to clear thinking.
If scientific records have become distorted for any reason, we need to know and should welcome any properly conducted studies that reveal and correct the distortions.

tgmccoy

Thank you. As usual, very in formative..

pkatt

This is what drives me crazy, start with an inexact system and proceed to twist it this way and that to suit whatever the current think wants it to be. I understand the desire to have a continuous record but in the many adjustments, one improper figure throws the whole thing off. Your system also assumes, that is a recipe for failure.
Considering that the Holocene has been underway for quite some time now I suspect that a 300 year record matters very little in the full scope of the suns life or cycles. Your “hasn’t changed in the last three hundred year” line.. is averaging?? Because if not you seem to be ignoring times when the sun has been active and inactive in our current times and recent past and if we have seen anything clearly, its that when the sun gets quieter for some reason it gets colder, and pretty darn quickly…. until you can explain this phenomenon keep at that drawing board because you are missing something EXTREMELY fundamental in the process.

John West

@ Dr. Leif Svalgaard
Is there a place we can get raw sunspot data back to as close to 1600 as possible, numbers that you would consider “good”?

TomRude

Please do not put words in my mouth. I was just asking and, just like Mobihci or Keith DeHavelle noticing the intensity of these 20C cycles, still stronger -according to properly accounted for sun spot counts- than 19C cycles. If not MGM why not Paramount for a naming?
BTW given these observed sun variations and the relatively short period of direct observation compared to let’s say the last glacial/interglacial time frame, what magnitude of variation would make you consider some direct control on Earth climate a possibility? In other words, for instance cycle 20 versus 21: top 140 spots versus top 80 spots, that is quite a serious variation – 43% in one cycle. Meteorologically the climatic shift of the 1970s is well documented -including in atmospheric pressure series all over the globe. Yet, we did not go to widespread glaciation, suggesting either buffering or a tamed role.

OssQss

Great read!
Thanks
i have learned a supplemental lesson with respect to the exercise of counting sun spots on a white background above. Ensure the monitor is properly cleaned prior to counting 🙂

Doug Huffman

@John West, File 1520 at his http://www.leif.org/research/?

davidmhoffer

AAAAAAAAAAAAAAAARGH!
I figured I’d put a red dot with a felt marker on the screen over every sun spot so I don’t count any twice. I checked twice, I was SURE is was dry erase….
[Reply: Hopefully a /humor;> but if not: Try increasing strength of solvents starting with water, then soap and water, then rubbing alcohol, then acetone (nail polish remover), then ‘organic solvent’ (hexane, gasoline). Hopefully it is a glass monitor and has no anti-reflection coating. If a flat screen / plastic, be very cautious with any thing beyond soap and water and test a corner / edge area first. On a flat screen / LCD hardening the ink and flexing the surface can sometimes flake it off (ice cube – as used with gum in hair). Good luck. -ModE]

PJF

Ensure the monitor is properly cleaned prior to counting 🙂
OMG, I might have to go back and tamper with my data series. 😉

I have to second the notion that if they have photos, a ‘recalibration’ from the original material ought to be possible / done. ( IF they trashed the negatives then “Oh Well”…)
When I learned lab work, we had a notebook in which ALL data and work were recorded. It was forbidden (got you an automatic “F” Fail grade) to have ANY erasure. If something needed changing, you put a line through and annotated why the following replacement was to be used. Does no-one do that any more? Is there no record of “Original raw counts and sizes, then factors applied, then resultant ‘counts'” sitting in some lab book archive at the observatory?
Seems like a pretty simple and very effective protection against just this kind of “Aw Shoot” retrospective oopsy fixing…
( The more I experience the product of professional science, the more I appreciate what was taught to me in High School Science classes… by a retired Lt. Colonel from the Air Force W.W.II who was also a retired research chemist from U.S. Steel. Had rather, um, strict rules about things… rules that prevented an awful lot of ‘issues’…)

William

Sunspot count is only a proxy for what happened to the sun in the past and what is happening to the sun currently.
What is currently happening to the sun? (i.e. Say the last three or four cycles which are fully instrumented.)
Why are the solar cycle 24 sunspots getting smaller? Why the abrupt change in the solar magnetic cycle? What are the theoretical implications of no sunspots?
How would the solar magnetic cycle restart if there were no sunspots?
http://www.solen.info/solar/
Why is the solar large scalar polar field declining? How low can it go?
http://www.solen.info/solar/polarfields/polar.html
Are there any other anomalous solar observations?

@Justthinking
>…what are the implications of that statement?
> (The consequences of not having had a Modern Grand Maximum.)
The lack of solar grand maxima is not devastating to the functioning of the Universe. But it does devestate certain pet theories of climate scientists/buffs, which claim to prove/disprove AGW or similar stuff.
😐

TRM

I got 22. I was so hoping for 42 so we would all have the meaning of life but that is another story. Great history and lucid description of a very interesting problem. Thanks.

davidmhoffer

[Reply: Hopefully a /humor;> but if not: Try increasing strength of solvents starting with water,
>>>>>>>>>>>>>
Nah, I do some really dumb things sometimes…OK, really often. I’m a continuous stream of mishaps.
Isopropyl alcohol cleans permanent marker up lickety split I’ve discovered.

John West

@ E. M. Smith
Yes, we still cross out, initial, and annotate except now it’s likely to be electronic, but not always (there’s still some archaic regulations that require actual notebooks).

PJF

Rubbing permanent marker ink with a dry erase marker will result in a wipe-off-clean blob on most surfaces.

kramer

A somewhat disturbing [to many people] consequence of the correction of the official sunspot number is that there is now no evidence for a Modern Grand Maximum [‘the largest in 8000 years’ or some such].
I knew as soon as I started reading this that this was going to be about the highest sunspot activity in the last 8000 years. Why? Because quite a few weaknesses in the science skeptics have been pointing out have been getting adjusted or modeled out by scientists later on.
I find it hard to believe that the science that worked against or weakened the case for AGW was wrong in all those cases.

TomRude says:
January 4, 2013 at 5:36 pm
Since Wolf started his observation in the middle of the 19 century and that “At the Royal Greenwich Observatory photographs of the Sun have been taken ‘every’ day since 1874 until they stopped in 1975. From these photographs the RGO determined the area of all sunspots for every day”, we are only talking about 25 years of observation
The RGO data is a 100 years and Wolf’s series is 160 years plus the data back to 1610, 400 years.
Since sun spot counts was introduced by Wolf “in the middle of the 19th century”,
Wolf invented his relative sunspot number around 1850, but dug up observations back to 1610 and constructed sunspot numbers back to about 1700. Wolf continued to 1893 and after that his successors have brought it up to the present day.
PJF says:
January 4, 2013 at 5:38 pm
This is generally regarded around these parts as a good thing. Yet some dismiss Dr Svalgaard’s project as “sunspot fiddling”. Very unfair and not conducive to clear thinking.
If scientific records have become distorted for any reason, we need to know and should welcome any properly conducted studies that reveal and correct the distortions.

Exactly, and that goes for any data set.
pkatt says:
January 4, 2013 at 5:47 pm
This is what drives me crazy
I don’t deal with crazy people. Come back when you have something substantial.
John West says:
January 4, 2013 at 5:48 pm
Is there a place we can get raw sunspot data back to as close to 1600 as possible, numbers that you would consider “good”?
No, not yet. But you can get a good approximation back to 1700 from SIDC’s website. Then multiply every number prior to the year 1947 by 1.2 and you’ll be close to what I think we will end up with.
TomRude says:
January 4, 2013 at 6:04 pm
BTW given these observed sun variations and the relatively short period of direct observation compared to let’s say the last glacial/interglacial time frame, what magnitude of variation would make you consider some direct control on Earth climate a possibility?
I think we have within the observed series about the full range the sun can do. There are other stars with much more violent cycles, but solar-type stars are rather sedate.
Doug Huffman says:
January 4, 2013 at 6:16 pm
I figured I’d put a red dot with a felt marker on the screen over every sun spot so I don’t count any twice.
just click on the image and you get a much bigger version.
E.M.Smith says:
January 4, 2013 at 6:38 pm
I have to second the notion that if they have photos, a ‘recalibration’ from the original material ought to be possible / done. ( IF they trashed the negatives then “Oh Well”…)
This is being done, but only gets us back to 1874. And the RGO photographs don’t have a constant ‘calibration’ themselves so don’t really help much. But were good enough to show the discontinuity in 1946.
then resultant ‘counts’” sitting in some lab book archive at the observatory?
It is sad to say, but it seems that Waldmeier destroyed or ‘disappeared’ all the archives from observatory. I have been there to check and the material is gone.
William says:
January 4, 2013 at 6:45 pm
Why are the solar cycle 24 sunspots getting smaller? Why the abrupt change in the solar magnetic cycle? What are the theoretical implications of no sunspots?
Many questions. We don’t know all the answers.
How would the solar magnetic cycle restart if there were no sunspots?
No sunspots does not mean the solar magnetic cycle has gone away. On the contrary, during the Maunder Minimum cosmic ray modulation was a strong as ever.
Why is the solar large scalar polar field declining? How low can it go?
It is declining becasue there are fewer spots to feed the field. Why there are fewer spots, we don’t know.
Are there any other anomalous solar observations?
Yes: http://www.leif.org/research/Disappearance-of-Visible-Spots.pdf
John Day says:
January 4, 2013 at 6:54 pm
The lack of solar grand maxima is not devastating to the functioning of the Universe. But it does devastate certain pet theories of climate scientists/buffs, which claim to prove/disprove AGW or similar stuff.
Yep.

DR

EM Smith said:

When I learned lab work, we had a notebook in which ALL data and work were recorded. It was forbidden (got you an automatic “F” Fail grade) to have ANY erasure. If something needed changing, you put a line through and annotated why the following replacement was to be used. Does no-one do that any more?

Here here! I learned that working in Aerospace. Every change, including serializing parts had to be lined out but still legible and identified with our Inspector/Engineer ID. On documents relating to them, same thing with date and annotations for the edit; virtually everything documented. Oh, and absolutely NO RED INK. Red=scrap. Pencils? Pack your things.
Being under FAA jurisdiction we would get in very big trouble scribbling, erasing or deleting data even if for tests being done incorrectly needing redoing; unacceptable and actionable if violated.
When discovering how things were done in climate science it was appalling to say the least the sloppiness and lack of archiving data, including Mulligans.

DirkH

davidmhoffer says:
January 4, 2013 at 6:32 pm
“AAAAAAAAAAAAAAAARGH!
I figured I’d put a red dot with a felt marker on the screen over every sun spot so I don’t count any twice. I checked twice, I was SURE is was dry erase….”
Next time use alt printscreen to copy the image into the clipboard. Use shift insert to copy into MS Paint or other paint program. Erase every spot you count with the eraser tool of the paint program.
That’s how I would do it at least. Avoid physical objects like felt markers when possible.

Andrejs Vanags

Have been Schwabe’s original counts been preserved, or are we in a position of just correcting Wolf’s corrections? In other words, can we always access the original uncorrected data?