Essay/paper by Dr. Leif Svalgaard
Abstract
As our civilization depends increasingly on space-borne assets and on a delicate and vulnerable earth-bound infrastructure, solar activity and its potential impact becomes of increasing importance and relevance. In his famous paper on the Maunder Minimum, Eddy (1976) introduced the notion that the Sun is a variable star on long time scales. After the recent decade of vigorous research based on cosmic ray and sunspot data as well as on geomagnetic activity, an emerging consensus reconstruction of solar wind magnetic field strength has been forged for the last century. The consensus reconstruction shows reasonable agreement among the various reconstructions of solar wind magnetic field the past ~170 years.
New magnetic indices open further possibilities for the exploitation of historic data. The solar wind is a direct result of solar magnetic activity providing an important link to the effects on the Earth’s environment. Reassessment of the sunspot series (no Modern Grand Maximum) and new reconstructions of Total Solar Irradiance also contribute to our improved knowledge (or at least best guess) of the environment of the Earth System, with obvious implications for management of space-based technological assets or, perhaps, even climate. Several lines of evidence suggest that the Sun is entering a period of low activity, perhaps even a Grand Minimum. Average space weather might be ‘‘milder’’ with decreased solar activity, but the extreme events that dominate technological effects are not expected to disappear. Prediction of solar activity has a poor track record, but the progression of the current Cycle 24 is in accordance with its behaviour predicted from the evolution of the solar polar fields, so perhaps there is hope.
Introduction
Solar activity is the result of solar magnetic fields.
If our Sun had no magnetic field it would be as dull as models of stellar constitution proscribe and we would not have this conference. The magnetic field makes the Sun interesting, which before the development of our technological civilization was of little consequence, but that the Sun is a variable magnetic star is today of immense practical importance; in fact, a potential danger to our modern way of life. Increasingly, our civilization depends on environmental conditions, communication devices, and infrastructures that are vulnerable to solar magnetic variability [NRC, 2008]. The famous Carrington Event in 1859 [e.g. Cliver & Svalgaard, 2004] can be said to mark the birth of this concern, although the technological effects, some even damaging with attendant economics loss, of geomagnetic disturbances [accompanied by brilliant aurorae] on the nascent telegraph communication capability were already noted more than a decade before.
To assess the impact of solar activity and the chances of effective mitigation of its effect we need to monitor and understand not only current space weather, but also space climatology: what is the equivalent of a ‘hundred-year flood’? Direct telescopic observation of solar activity, of course, begins with the discovery 402 years ago of sunspots. Our understanding of that historical record forms the basis for interpreting the indirect evidence both from natural archives (e.g. 10Be from ice cores) and human naked-eye observations (aurorae, 日誌 [ri-zhi] blemishes on the sun) stretching much farther back in time.
The Sunspot Record(s)
The historical sunspot record was first put together by Rudolf Wolf in 1850s and has been continued by Wolf and his successors followed by a more ‘institutionalized’ approach later in the 20th century until today and hopefully beyond. Wolf’s original definition of the Relative Sunspot Number for a given day as R = 10 Number of Groups + Number of Spots visible on the solar disk has stood the test of time and recognizes [in Wolf’s own words] that the emergence of a coherent group of spots (an active region) is much more important than the addition of yet a few spots to an existing group. The factor of 10 has also turned out to be a good choice as historically a group contained on average ten spots.
A fundamental problem is the homogeneity of the series, that is: does a relative sunspot number of 100 mean the same level of solar activity today as it did in 1938, in 1872, or in 1739? And what is a useful definition of ‘solar activity’ anyway? From the viewpoint of solar effects on our technological infrastructure, the solar wind – the ever present expanding outer atmosphere of the Sun – is perhaps the most relevant element, although bursts of highly energetic particles and radiation also degrade devices and spacecraft and threaten humans in space. Almost all solar indices and solar wind quantities show a relationship with the Relative Sunspot Number [SSN], so homogeneity and proper calibration of the SSN become of utmost importance.
Hoyt et al. [1994] in a series of papers at the centenary of Wolf’s death asked “Do we have the correct reconstruction of solar activity?” and proposed to answer the question in the negative. A heroic effort from an extensive search of archives and primary sources yielded ~350,000 observations, many not available to Wolf, covering the interval 1610-1993. An earlier study showed that the ratio of individual spots to groups is nearly a constant. Theoretical arguments [Schaefer, 1993] showed that Wolf’s Relative Sunspot Number may be set equal to a constant times the number of sunspot groups, so an index based solely on the number of sunspot groups can simulate the Wolf SSN. Hoyt & Schatten called this index the Group Sunspot Number [GSN] and found that it appears that solar activity has steadily increased since 1700 to what might be called a Modern Grand Maximum in the latter part of the 20th century. Before ~1885 the GSN is significantly smaller than the Wolf SSN which does not support the idea of a Modern Grand Maximum. This discrepancy is not satisfactory and must be resolved so solar-terrestrial researchers have a stable and unique dataset to work with.
Recognizing the need to resolve this issue, a number of workshops on the calibration of the sunspot number have been sponsored by the National Solar Observatory (NSO), the Royal Observatory of Belgium (ROB), and the Air Force Research Laboratory (AFRL) as an effort to provide the solar community with a vetted long-term (single) sunspot number series and the tools to keep it on track. The first workshop was held at Sunspot, New Mexico [yes, there is such a place] in September 2011, followed by a second workshop in Brussels in May 2012. Further meetings will take place in 2013 in Tucson, AZ and then in Switzerland. We are considering a special Topical Issue of Solar Physics for the eventual joint publication of the SSN series and the accompanying historical, procedural, and scientific papers. In this paper, I’ll report on the progress made so far.
An efficient way of comparing the Wolf Sunspot Number and the Group Sunspot Number is to plot the ratio between them as shown in Figure 1. That removes most of the solar cycle variation and will show obvious discontinuities caused by non-solar related changes in the calibration. Figure 1 shows two clear discontinuities, one near 1945 and one near 1885.
Figure 1: Ratio between monthly values of the Group Sunspot Number (Rg) and the Wolf (Zürich, International) Sunspot Number.
Explaining those will go a long way to resolve the differences between the two series. We shall show that the 1945 discontinuity is a problem with the Wolf Number while the 1885 discontinuity is a problem with the Group Number. When both problems are corrected, there is no longer a significant difference between the two series.
The Waldmeier Discontinuity
Some time in the 1940s the observers in Zürich began to weight sunspots when counting them. The director of the Zürich Observatory, Max Waldmeier described [Waldmeier, 1968] the procedure thus “A spot like a fine point is counted as one spot; a larger spot, but still without penumbra, gets the statistical weight 2, a smallish spot with penumbra gets 3, and a larger one gets 5.” This weighting increases the spot count by 45% on average and, since the spot count is half of the Relative Number, the SSN by approximately half that.
The Locarno Station in Southern Switzerland has since 1957 served as an auxiliary observer for Zürich [as the weather on opposite sides of the Alps often is complimentary] and is still today the reference station for the modern sunspot number maintained by SIDC in Brussels, as all other observers are normalized to Locarno’s count. Locarno is still weighting the spots according to Waldmeier’s prescription, so the weighting carries over fully into the current sunspot number. Normalization is done by applying a factor, k, in the formula for the Relative Sunspot Number R = k (10 G + S) such that different observers of the number of groups, G, and the number of spots, S, arrive at the same relative number, R. The k-factor depends on several things: telescope aperture and magnification, observer acuity, atmospheric seeing, and the precise way spots are recognized and grouped. The Zürich observers after Wolf chose to count all spots that were visible, while Wolf did not include the smallest spots near the limit of detectability, in order to be compatible with Schwabe’s observations. Consequently, a k-factor of 0.6 was, at first, empirically determined and later simply adopted to reduce the sunspot number to the original Wolf scale.
Figure 2 shows the effect of weighting using a typical drawing from Locarno. There is also a small contribution from an improved classification of sunspot groups introduced at about the same time. The combined net effect is to increase the sunspot number since ~1945 by ~20%. This explains the discontinuity in the ratio GSN/SSN at that time. A strong check and confirmation of the effect of the weighting have been carried out the past year by the Locarno observers, counting both with and without weighting, so the magnitude of the effect of the weighting is now established and is no longer an open issue.
The effect of the weighting turns out to be almost independent of solar activity, so a simple corrective action would be to multiply all numbers before 1945 by 1.20. Figure 3 shows the result of the correction. Such ‘wholesale’ correction is not without precedent. In 1861 Wolf published his first long list of the SSN covering the years 1749-1860. Around 1875, Wolf increased all the numbers on the 1861 list before 1848 by 25%, based on measurements of ‘the magnetic needle’, which we’ll hear more about later in this paper.
Figure 2: (Left) Part of a drawing made at Locarno, showing that the spot with penumbra designated 104 was counted three times (weight 3). (Right) Two spots with the same area on drawings from Mt. Wilson and counted with weight 1 by Wolfer, in each case as one group with one spot (Wolf’s notation: groups.spots = 1.1), as the group was the only group on the disk
Figure 3: Removing the effect of weighting after 1945 removes the discontinuity in 1945. There remains the discrepancy around 1885.
The lower panel shows the corrected SSN (Rz) in blue and the GSN in pink. Note that the corrected SSN reaches about the same level in each century
Group Sunspot Number Calibration
Hoyt & Schatten [H&S] quickly found that the constant that converted a group count to a simulated Wolf Relative Number was not a constant at all, but varied with the observer, and was, in effect, a k-factor to be applied to the number of groups. A decision must be made as to which observer should have a k-factor of unity. H&S chose the ‘Helio-Photographic Results’ tabulations from Royal Greenwich Observatory [RGO] covering the years 1874-1975 as their ‘standard’ observer. Because Wolf and successor Alfred Wolfer observed from 1848 through 1928 with overlap 1876-1893, their combined observations can serve as a ‘backbone’ for the determination of k-factors for other observers overlapping with them before the RGO series begins. H&S determined that the ratio between k-factors for Wolf and Wolfer was 1.021, i.e. that both observers saw very nearly the same number of groups. And herein lies the problem.
Because of extensive travel and other duties, Wolf from the 1860s until his death in 1893 exclusively used a small, handheld telescope, while Wolfer used a larger 80mm Fraunhofer telescope similar to what Wolf used earlier. Both telescopes still exist (Figure 4) and are even in use today by Thomas Friedli in Belp, near Bern, continuing the Wolf tradition.
Figure 4. (Left) the 80 mm Fraunhofer refractor used since 1855 by Wolf and successors. (Center) the same telescope in use today by Thomas Friedli (person at right). (Right) the 37 mm portable telescope used by Wolf since the mid 1860s.
Figure 5 shows that for the time of overlap between Wolf and Wolfer, Wolfer counted [as appropriate for the larger telescope] 1.653 times as many groups as Wolf, and not only 1.021 times as determined by H&S. This discrepancy is the main cause of the 1885 discontinuity in the GSN/SSN ratio. We can understand the reason why Wolf saw so few groups by considering that the small spots making up groups with Zürich classifications a and b (groups containing spots without penumbra) are usually not visible in Wolf’s small telescope. Such groups make up about a half of all groups.
Figure 5: (Top) Number of groups observed by Wolfer compared to the number observed by Wolf. (Bottom) Applying the k-factor of 1.653 makes Wolf’s count (blue) match (yellow) Wolfer’s count (pink)
Figure 6: Different colors (hard to see because they fall on top of each other) show the individual contributions to the composite (bright cyan). The black dashed curve is the Zürich SSN / 12 (to convert it to number of groups).
Using the Wolf-Wolfer composite record as a backbone, we can now confidently determine k-factors for 22 mutually overlapping observers stretching back to Schwabe and forward to Brunner and construct a composite series. As Figure 6 shows there is now no significant difference between the GSN and the SSN. So, with only two adjustments: ~20% for SSN before 1945 and ~50% for GSN before 1885, the discrepancy is resolved. The issue of the very early data, say before 1825, is still open and is the target for the next SSN Workshop, but if people can accept the current series without adjustments, then they might also accept that we, for now, assume that there are no further adjustments warranted for the early data.
Geomagnetic Calibration of Sunspot Numbers
Wolf [1852] discovered a beautiful connection between sunspots and the diurnal variation of the Earth’s magnetic field. He marvelled “Who would have thought just a few years ago about the possibility of computing a terrestrial phenomenon from observations of sunspots”, and he at once realized that such a relation could be used as an independent check on the calibration of the sunspot number. Today we understand the physics of that connection and can fully validate Wolf’s assertion. Solar Far Ultraviolet [FUV] radiation creates and maintains the conducting E-layer in the ionosphere. Thermal winds driven by solar heating move the charges across the Earth’s magnetic field setting up an ionospheric dynamo with currents generating magnetic effects observable on the ground. As the Earth rotates under the currents (which are fixed in direction to the Sun) a characteristic diurnal perturbation of the geomagnetic field is readily observed (discovered by Graham in 1722). The diurnal variation is best seen in the East component of the geomagnetic field. The 10.7 cm microwave flux from the Sun is a good proxy for the FUV flux and Figure 7 shows how well the amplitude of the diurnal variation tracks 10.7, thus validating Wolf’s procedure using modern data.
Figure 7: 10.7 flux correlation with the range, rY, of the diurnal variation of East Component
The Figure also shows the ‘equivalent’ 10.7 flux calculated from the observed range (average of nine stations) of the diurnal variation for many solar cycles before the advent of the flux radiometers. It is clear that the well-understood physics of causes of the diurnal variation of the geomagnetic field provides a reliable way of assessing the past variation of solar flux, and hence the magnetic activity responsible for it; a variation for which the sunspot number is a proxy. Careful application of this method fully supports the two adjustments of the sunspot series described above based on the diurnal variation as observed since the 1780s.
Solar Wind Properties in the Past
Direct in-situ observation of the solar wind goes back 50 years and it was clear from even the earliest data that geomagnetic activity (separate from and superposed on the regular diurnal variation just discussed) was directly controlled by the expanding solar atmosphere – by the expansion speed and by the strength and direction of the magnetic field dragged out from the Sun. Recent research [Svalgaard & Cliver, 2005, 2007, 2010; Lockwood & Owens, 2011] has shown that it is possible to infer the solar wind speed and the magnetic field strength from suitable, newly defined, indices of geomagnetic activity that have been found to respond to different combinations of these solar wind parameters, allowing the influence of each to be separately extracted and calibrated by comparison with the space-based data measured near the Earth, effectively inverting the ‘response function’ of the Earth to the solar wind. Figure 8 shows one result of this inversion.
Figure 8: Heliospheric magnetic field strength B at Earth inferred from the IDV geomagnetic index (blue) and observed by spacecraft (red). Data before 1872 (light blue) are preliminary and can be improved by adding more 19th observatory data.
Data exist to carry this inversion back to the earliest systematic observations of the geomagnetic field in the 1830s. We find that the reconstruction of the solar wind is consistent with the re-assessment of the sunspot number series described above, in particular that there also does not seem to have been a Modern Grand Maximum in solar wind parameters. Another finding of interest is that even during periods of extremely low solar activity [e.g. the years 1901-1902, 2008-2009] the solar wind is still present having a respectable magnetic field of about 4 nT. An important research issue at present is whether this minimum state of solar magnetic activity, a ‘floor’, is a general feature, at all times [Schrijver et al., 2010]. Recent work by Owens et al. [2012] suggests that “even a steady decline in sunspot number may result in a plateau in the Open Solar (magnetic) Flux”.
The Cosmic Ray Record
Cosmic ray particles reaching the Earth are mostly produced outside the solar system during supernova explosions. Two time-varying magnetic ‘shields’, the solar magnetic field and the geomagnetic field, modulate the cosmic ray flux. The weaker these fields, the higher is the cosmic ray intensity near the surface of the Earth. Ionization chambers and neutron monitors have directly monitored the intensity of cosmic radiation since the 1930s [Steinhilber et al., 2012]. Before that, no direct measurements exist, and cosmogenic radionuclides, are used as a proxy for cosmic radiation, especially 10Be and 14C, produced by cosmic rays colliding with atmospheric nitrogen and oxygen. Thus, the production rates of these nuclides are related to the flux of the incoming cosmic rays. As with the sunspot number, there are issues with the proper calibration of the cosmic ray proxies. What are measured are not variations of the production rate, but of the deposition rate, which in addition to the incoming flux also depend on atmospheric circulation and climate in general. Inversions of the ionization chamber data to extract the strength of the solar magnetic field are discordant with inversions of the neutron monitor data and with the result of the geomagnetic constructions. This issue will eventually be resolved and a special ISSI workshop towards this goal is ongoing [Svalgaard et al., 2011].
Of special interest is the cosmic ray record of so-called ‘Grand Minima’, like the Maunder Minimum. The solar magnetic field (expressed as the near-Earth solar wind magnetic field) extracted from the cosmic ray record falls to zero or at times is un-physically negative during Grand Minima (Figure 8) while at the same time a vigorous solar cycle modulation of the cosmic ray flux is observed [e.g. Berggren et al., 2009, Figure 9] indicating to this author that significant solar magnetic field was present.
Figure 8 [left]: Heliospheric magnetic field strength at Earth inferred from the cosmic ray record [Steinhilber et al., 2010]. The deep excursions to zero or even un-physical negative values are not understood and may be artefacts caused by too aggressive extrapolation from modulation potential to field strength. This is presently an open and controversial issue.
Figure 9 [right]: (Top) 10Be flux from the NGRIP ice core (Greenland). (Bottom) The 10Be data band pass filtered at 8–16 years [Berggren et al., 2009]. The red curve is the filtered GSN series.
Similarly, observations of the spicule forest (the ‘red flash’) during the total solar eclipses in 1706 and 1715 seem to require the presence of bright network structures, and thus of substantial solar photospheric and chromospheric magnetism during at least the last decades of the Maunder Minimum [Foukal & Eddy, 2007].
The very long cosmic ray record (when calibrated and understood correctly) provides the necessary material for statistical studies of the frequency and features of extremes of solar activity (the ‘500-year floods’). The first order of business is to understand why the variations are discordant compared to other solar indicators the past 400 years. This effort is ongoing and the results are not yet in sight.
Predicting Solar Activity
At this point in time it has become of great practical and societal importance to predict solar activity and space climate, rather than just recording them, e.g. for planning mitigation of the effects of extreme solar events. The NASA/NOAA international Panel for Predicting the Solar Cycle examined 75 ‘predictions’ of the current Cycle 24, basically covering the full spectrum of possible outcomes centered on the climatological mean, from extremely small to extremely large [Pesnell, 2012]. The Panel ended up (barely) endorsing the ‘precursor’ methods as the most promising where some property of the Sun near minimum is used as a predictor of the following cycle.
On physical grounds, the magnitude of the polar fields of the Sun seems to be a good candidate as a precursor as it is thought that the polar fields act as a ‘seed’ for the dynamo producing the next cycle [e.g. Jiang et al., 2007]. Leading up to the minimum in 2008, the polar fields were the weakest ever observed (since the invention of reliable solar magnetographs in the 1950s) prompting Svalgaard et al. [2005] and Schatten [2005] to predict that cycle 24 would be ‘the smallest cycle in a hundred years’. This prediction has, so far, held up well, providing (together with predictions using other precursors, such as the geomagnetic aa-index) a successful test of the precursor notion. Figure 10 compares the polar fields and the size of the next cycle for the past several cycles.
Figure 10a: The axial magnetic ‘dipole moment’ of the Sun, defined as the difference between the (signed) magnetic field strength near the North Pole and near the South Pole, for the past four solar cycles. To facilitate comparison of cycles, a ‘ghost’ mirror image is also plotted. Data from Mount Wilson Observatory (blue) has been scaled to match observations from Wilcox Solar Observatory (red).
Figure 10b: The polar field variation at the left scaled by the maximum smoothed sunspot number for the next cycle suggesting the same variation for each cycle, i.e. that the cycle maximum is controlled by the polar fields at the preceding minimum. For Cycle 24, the maximum was not known, but a very high value (165) or a very low value (45) does not fit the pattern. A maximum size of 72 for Cycle 24 seems to be the just right ‘Goldilocks’ value.
Figure 11 shows how the prediction is doing. The quantity plotted is the total number of active regions per month on the disk within 70º of Central Meridian (which is on average 2.25 times the sunspot number).
Figure 11: Numbered active regions within 70º of CM per month. Different cycles are plotted with different colors. The predicted Cycle 24 is shown as the dashed purple curve. We are very close to a drawn out solar maximum at this time of writing.
Recent Changes in the Sun?
Historically all solar indices have been closely correlated as they all derive from the same source: the variable magnetic field. In fact, the various reconstructions of past (and predictions of future) activity all rely on the implicit assumption that the correlations stay the same over time. This is likely to be true for indices that have a close physical connection, like the 10.7 and UV fluxes, but is not given a priori for correlations that are more indirect, e.g involving the sunspot number: the processes creating visible sunspots are varied and not fully understood. And indeed, while there has long been a stable relationship between the 10.7 flux and the sunspot number, allowing one to calculate or map one from the other, that relationship has steadily deteriorated in the past decade to the point where the sunspot number for a given flux has decreased by about a third (Figure 12).
Figure 12: The observed SSN divided by a synthetic SSN computed from a polynomial fit to the 10.7 flux over the interval 1951-1990. Red points are SIDC sunspot numbers while blue points are SWPC (NOAA) sunspot numbers scaled down by the their average k-factor of 0.655. Only years when the SSN was above 10 are included. Since ~1990 the observed SSN is progressively lower for a given 10.7 flux.
A similar decrease of the sunspot number for a given amount of magnetic flux in the plages surrounding active regions has occurred as well as a decrease of the number of spots per active region. This is unprecedented in the observational record. We interpret this decrease as a loss of primarily the small spots [Lefevre & Clette, 2012].
Observations by Livingston & Penn since 1998 until the present show that the average magnetic field in sunspots has steadily decreased by 25% [Livingston et al., 2012], regardless of the fact that we are now again at the maximum of a solar cycle, so there has not been a solar-cycle-related reversal of the trend. Since their magnetic fields cool sunspots, a decreasing field means that sunspots are getting warmer and that their contrast with the surrounding photosphere is getting smaller, making the spots harder to see. There is a minimum field strength in visible spots of about 1500 Gauss [0.15 T] and as that 1500 G threshold is approached, magnetic fields appear at the solar surface which do not seem to form dark sunspots or pores. Owens et al. [2012] suggest that the photospheric flux emergence in such cases may take place in flux tubes with field too weak, or of too small a diameter, to form sunspots, citing Spruit [1977]. The observed distribution of number of spots vs. field strength has been shifting steadily towards that limit. If, and that is a big IF, this trend continues, the number of visible spots in the next cycle [and perhaps beyond] may fall to values not seen since the Maunder Minimum, but without dramatic changes in the emerging magnetic flux. Without the dark spots, Total Solar Irradiance might even be a bit higher. It is not clear what this will mean for the impact of solar activity on the Earth’s environment, if any, but it portends exciting times for solar physicists.
Discussion
Our technological civilization has reached a point where solar activity and its prediction on all times scales have become significant factors in maintaining and safekeeping of the technological infrastructure, both on the ground and in space. New capabilities, in instrumentation, deployment, computer storage and power, and – last, but not least – increased awareness promise progress towards predictive improvements. On the other hand, if the Sun is moving into a new regime of lower activity, a period of uncertainty may make life hard for the forecaster. The possible, recent re-assessment of past solar activity should provide a better benchmark for theoretical modelling to meet. If the discrepancy between the sunspot number and other solar indices continues, it may be that the SSN, for a while, is no longer a good measure of solar activity and forecasters (and users) may be forced to rely on other indices for operational use. This does not mean that we should stop deriving the sunspot number from the usual visual observations; on the contrary, the evolution of the SSN must be followed closely in order to provide a continuing basis for assessing the historical record.
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Acknowledgements
The author thanks Ed Cliver for serving as a long-suffering sounding board for my wilder ideas. I also thank Phil Scherrer at Stanford for support and I have benefited from participation in the International Teams in Space Science [ISSI] Workshop on ‘Long-term reconstruction of Solar and Solar Wind Parameters’ and from the Sunspot Number Workshops http://ssnworkshop.wikia.com/wiki/Home
This paper was a keynote presentation at the ”TIEMS, Oslo Conference on Space Weather, 2012″
Jurgen says:
November 12, 2012 at 6:46 pm
About this Dunning-Kruger thing: skill, or knowledge for that matter, is a relative thing, as it can easily get in the way of new developments and insights. There is this thing you may call “knowledge bias”: the more you know, the more selective your perception tends to become. It is a bit like a Faustian price you have to pay once you get too stiff with what you know.
Not knowing something can be an advantage, depending on the situation. Knowledge usually is context-specific, and may very well become useless outside this context.
The art is to know what to know and when to use or not to use this knowledge. This is especially so doing frontier work or creative work.
Not taking sides here, just want to add some perspective.
Ray: Well said Jurgen. I wish the moderators (if there are some) would warn people about saying this DK stuff.
Leif Svalgaard says:
November 12, 2012 at 6:57 pm
Jurgen says:
November 12, 2012 at 6:46 pm
About this Dunning-Kruger thing:
Thanks for the comment Leif, I am a bit slow reacting to it as I was already way too far in the little hours of the early morning.
Psychology is messy. In my opinion it is not a proper science. As with other social sciences it gets inevitably too much entangled with all kinds of human values, goals and politics to be able to apply the strict rules of physical science. Still, the social sciences may be useful for practical purposes if you realize this difference. But again, it is messy.
As for you diagnose of Mr. Vukcevic, I rather go with your good information on solar activity. Your efforts are much appreciated.
Johanus says:
November 12, 2012 at 8:18 am
“So, the correlation (Maunder::low_temps) is not a cause. And “What else could it be?” won’t fly as scientific proof either.”
It has been sufficient for CO2 to be labeled the cause of the modern rise in temperatures.
That is all they’ve done, “there’s nothing else, so it has to be CO2, and see the model I explicitly constructed so calculated temps rise with co2 is proof”!
I don’t know when that became “Science”, and I don’t understand how so many “Scientists” can stand there and not say anything.
Jurgen says:November 13, 2012 at 5:24 am
Thanks for the comment Leif. As for you diagnose of Mr. Vukcevic, I rather go with your…
Jurgen
Thanks, you saved me shrink’s fee, no need to look for a second opinion.
Beside
http://www.vukcevic.talktalk.net/GSC1.htm
there is this
http://www.vukcevic.talktalk.net/TMC.htm
and
http://www.vukcevic.talktalk.net/SSN-NAP.htm
not to mentioned
http://www.vukcevic.talktalk.net/LFC2.htm
all are apparently impossible, spurious or outside of knowledge box of science. I only bring to your attention what is in the data, no more than a simpleminded messenger.
Far too many people take themselves too seriously.
BTW, Jurgen what did you make of that poor chicken? in :
L.S. Sadly, you remind me of http://mentalfitnessnow.com/category/mindfulness/
Jurgen says I am a bit slow reacting to it as I was already way too far in the little hours of the early morning.
Jurgen go and ‘sleep on it’.
I think tallbloke and others need to be careful when ascribing warming to the sun. There may have been no warming at all. With all the adjustments to reduce historic temperatures necessary to create warming and when it is very possible they are wrong, the basis of your argument may be mistaken. If so, the 1930s were as warm as we are right now and there is no need to ascribe something to the sun that doesn’t exist.
This leads into a conjecture I have been forming and may have mentioned before. I would like to know if anyone knows of any work along these lines. The theory itself is quite simple:
Solar magnetic storms (CMEs) lead to short term reduction in clouds on Earth. During these periods of a few days to a couple of weeks the planet receives more solar radiation and warms. These short term warming bursts work to generally warm the planet over what would otherwise occur.
Naturally, it would be difficult to tease a signal out of short term noise since this small but persistent effect looks exactly like noise. The long term effect (at least during the present mode of Milankovitch cooling) would be a warming when there are more CMEs and cooling when there are fewer of them. If there are fewer CMEs when the Sun is quiet, then we would expect those times to cool. That could explain the Maunder and other cool periods.
This conjecture might even have impacts on the faint sun paradox. So, does anyone know of any work in this area?
Ray Tomes
In creative science work,and that hasn’t been in quite some considerable time given what passes for science today,you are expected to have an overall picture and know what to discard,what to accept,what is irrelevant,how to move information around between disciplines and all the things mechanical or computer modeling cannot do.Poor Leif here had a bad day and let his assertions run out of control.
Try Pascal –
“There are different kinds of right understanding; some have right understanding in a certain order of things, and not in others, where they go astray. Some draw conclusions well from a few premises, and this displays an acute judgment.Others draw conclusions well where there are many premises”
http://oregonstate.edu/instruct/phl302/texts/pascal/pensees-a.html#SECTION I
The idea of the Earth as a greenhouse and pumping carbon dioxide into the atmosphere has the same effect as a greenhouse would be laughable as a premise were it not that the opposing side lack any sort of foundation for defining planetary climate or seem intent in joining the modeling pseudoscience.
I have little hope that readers could understand Pascal properly as he himself said the ability to balance conceptions and perceptions is rare in the individual and rarer still in this atmosphere of mathematical modeling yet perhaps it will ring true for one or two readers who understand that ‘intuitive’ does not equate with ‘guesswork’ but rather than background against which conclusions are drawn and information gets moved around –
”All mathematicians would then be intuitive if they had clear sight, for they do not reason incorrectly from principles known to them; and intuitive minds would be mathematical if they could turn their eyes to the principles of mathematics to which they are unused.
The reason, therefore, that some intuitive minds are not mathematical is that they cannot at all turn their attention to the principles of mathematics. But the reason that mathematicians are not intuitive is that they do not see what is before them, and that, accustomed to the exact and plain principles of mathematics, and not reasoning till they have well inspected and arranged their principles, they are lost in matters of intuition where the principles do not allow of such arrangement. They are scarcely seen; they are felt rather than seen; there is the greatest difficulty in making them felt by those who do not of themselves perceive them. These principles are so fine and so numerous that a very delicate and very clear sense is needed to perceive them, and to judge rightly and justly when they are perceived, without for the most part being able to demonstrate them in order as in mathematics, because the principles are not known to us in the same way, and because it would be an endless matter to undertake it. We must see the matter at once, at one glance, and not by a process of reasoning, at least to a certain degree. And thus it is rare that mathematicians are intuitive and that men of intuition are mathematicians, because mathematicians wish to treat matters of intuition mathematically and make themselves ridiculous, wishing to begin with definitions and then with axioms, which is not the way to proceed in this kind of reasoning. Not that the mind does not do so, but it does it tacitly, naturally, and without technical rules; for the expression of it is beyond all men, and only a few can feel it.”
I found Leif’s discussion here interesting and non-controversial. (Think you Dr. Svalgaard!!) Note that he is providing a status update of an international effort of a number of scientist which is of great interest to the solar community (AFRL’s involvement is telling). I do not know this for a fact, but I feel confident that this group does not have a CAGW agenda one way or another.
Concerned as I am about civility on WUWT and having some time today so I analyzed the dialog between Geoff Sharp and Leif. I started with Geoff Sharp because his was the first criticism. To wit: “The GSN values are questioned by some but their argument have holes that have yet not been answered.” The first element of the supporting argument appears to be: “Schatten seems to have had a memory loss on the method used but there are two k factor columns against each observer that are not explained.” This must be a reference to something not in Leif’s discussion and no link was provided. As presented, the point has little content. The next element of the criticism appears to be: “Of more importance is that H&S were 100% aware of the Wolf and Wolfer method of counting groups as can be seen in the data notes associated with Wolf’s BIBLIOGRAPHY notes that form the base data of the GSN.” This again refers to information not presented and again strikes me as a statement whose relevance is implicit and which escaped me. Then we get to the unambiguous criticism which is an ad-hominem attack: “Leif is in the business of ironing the record flat, agenda driven science should be accepted for what it is and more heavily scrutinized.”
Geoff’s next post – is a link to his critique of the Livingston and Penn effect with references to other presentations. This is reasonable with the caveat that there is a lot of related published activity and presentations in 2011 and 2012 so the science is evolving. After about an hour of review, I could not convince myself that the DeToma Brussels presentation in May 2012 was contradicting the content of the September 2012 Livingston, Penn and Svalgaard paper. In any event, the validity of the L&P effect is a footnote to the historical record reconstruction Leif is reporting to us.
There is some more ad-hominem back and forth between various posters. Geoff then complains about Mosher’s comments getting approved before his. I have noticed this on my comments from time to time and am convinced there is no WUWT moderator conspiracy to control the discourse at work here!
What saddens me here is that Geoff has some good work on his site. The reputation of his work is lessened by his resorting to an ad-hominem attack. I think one of the most interesting results Leif reports is that a significant body of work: Hoyt & Schatten published (and presumably peer reviewed) in the mid 90s must be re-analyzed. A solid critique on whether the re-analysis is justified would be far more useful than what Geoff originally posted. If indeed the Hoyt and Schatten work had errors, it would be interesting to understand how they were undiscovered for so long.
vukcevic says:
November 13, 2012 at 6:50 am
Jurgen says:
Thanks for your comments.
Leif may be blunt some times, but I give him credit for his honesty. Whether you agree with him or not, he is transparent and that is a big pro.
You asked for my opinion on the chicken story. I see a similarity with this Dunning-Kruger idea. In itself the DK phenomenon in my opinion does exist. In actual fact I think it is pretty wide spread and has many variations also within the scientific community. The problem of course is to diagnose it correctly, within yourself and within others.
The chicken is wired not to recognize the fence as a fence. In his normal natural environment if she can see through something, she can pass through it. In a sense a human belief may act the same way and there you have the DK mechanism. As knowledge and believe tend to organize our perception of the world around us, we start selecting information which means we leave information out as well to the extent we are kind of blind for it, it simply does not get through our perception sieve.
I think these are fundamental general characteristics of our information processing. We all are subject to it, scientist and amateurs alike. An amateur may happily go along with it, but a scientist may not, his professional standards require him to subject himself to the “DK-test” on a regular basis. Maybe not by going to a shrink, but by being open to critique from others who can detect his blind spots he himself can not. A forum like this gives plenty of opportunity for that. In that sense an honest critique is more of a gift and less of an attack.
Maybe this elaboration is a bit OT but as mr. Svalgaard and mr. Vukcevic do regularly clash, I hope some perspective here may serve a purpose.
Figure 8 [left]: Heliospheric magnetic field strength at Earth inferred from the cosmic ray record [Steinhilber et al., 2010]. The deep excursions to zero or even un-physical negative values are not understood and may be artefacts caused by too aggressive extrapolation from modulation potential to field strength.
Whatever cosmic ray causes, the records of the last three millennia after Steinhilber et al. 2010, it can be compared with solar tide functions of five relevant outer couples in the solar system:
http://www.volker-doormann.org/images/cosmic_r_vs_solar_tide.jpg
It seems that the time scale calibration of the cosmic ray spectrum is not referenced on astronomical landmarks; to fit the time scale of the tide function it was slightly calibrateted by
~ +10%.
If this is a fact, it means that the geometry of solar tide functions have a connection to the cosmic ray frequncies and to the global temperatures.
V.
Leif Svalgaard says:
November 12, 2012 at 9:26 pm
“How do you generate a current in a plasma? To do this you have to separate charges of different signs. How do you do that? With a magnetic field…”
Leif, you are usually infallible (any indication to the contrary we ignore). But to generate an electric current in a plasma, all you have to do is accelerate the plasma. The electrons get going faster than the protons, hence the electric current and the orthogonal magnetic field. This is the principle behind magnetohydrodynamics.
Jurgen says: November 13, 2012 at 11:21 am
……..
Jurgen
You need to revisit your old text books. Dr. Svalgaard and I are really good friends and enjoy a bit of a friendly banter, he is a scientist of world repute, I am an ordinary Joe blog .
On the psychology front, perhaps you know what you are talking about, I have no slightest idea, so you psychology expertise may be valued more elsewhere, it’s all a bit of voodoo ‘science’ to me.
Thanks for the bit of theory on the chicken’s psychoanalysis, btw, I gather the chickens–specifically for sacrifice—are big in the voodoo.
Hope you had a good sleep.
Thanks!
The comments do take the safe road though by limiting them to the safe ground of variation effects on technology in place of the more pressing issue of solar variation NOT incorporated in climate models to any meaningful extent. The climate models that minimize solar effects and hold ocean cylces as effectively constant cycle variations are harming science and public policy simultaneously. Avoiding controvery on these huge issues does not make them go away.
Resource guy.
I know,you think this website here thinks it is influential and maybe even has a hint of moral superiority against modeling which effectively would load the rest of humanity with an awful premise that the Earth is a greenhouse with humanity in charge of the temperature dial within .
From my seat ,this website has about the same influence as say ,’Occupy Wall Street’ for all the modelers care for the simple reason that they own the education system.I am not talking of the anti-competitive peer review process at the University level where reputations and salaries rely on bandwagon ideologies but rather by the young kids who are given games to play on zapping ‘bad carbon dioxide ‘ molecules and if the modelers understand one thing it is time is on their side.
We exist in an era where ‘science’ can’t even keep one rotation of the Earth in step with one 24 hour AM/PM cycle because every adult here was once a child and learned the idiotic reasoning back in high school and now can’t change,not even when daily rises and falls in temperature respond to one rotation of the planet.Now that is power over the individual and the community,it may be wrong but it is what it is.
Clouds pass overhead. Chicken crossing road sees pattern in light falling on pavement.
Chicken looks up at source of pattern, sees Sun. Chicken stares at Sun until Chicken sees Sun pulsing.
Chicken doesn’t see approaching truck.
Question: Why did Chicken cross the road?
Answer: “Why” is irrelevant. The mechanism was transfer of momentum from the truck, which can be read about in a physics textbook. There is no provable significant correlation between possible patterns in sunlight and chickens crossing a road by the momentum-transfer mechanism.
Moral: Looking for patterns on the Sun blinds you to real effects from proven mechanisms. Don’t be Chicken, keep looking around lest you become roadkill.
vukcevic says:
November 13, 2012 at 12:10 pm
Jurgen says: November 13, 2012 at 11:21 am
mr. Vukcevic,
thanks for you comments – it answers some questions I had. It is clear for me now I don’t need to be ashamed the graphs you link to are voodoo science to me as well. But they look beautiful.
Kadaka
Chicken survives and goes home,wakes up in the next morning to see the same Sun and lets out a morning call,does the same thing the next day and the day after that and so on.The chicken knows something humans do not –
“The Earth spins on its axis about 366 and 1/4 times each year, but there are only 365 and 1/4 days per year. ” NASA
http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970714.html
There was an old mathematical trick some are familiar with as kids where you prove you have 11 fingers –
http://best-magic-tricks.blogspot.ie/2006/06/prove-that-you-have-11-fingers.html
The NASA statement is more or less an astronomical version of this trick and the dismaying part is not that it is easy to spot and correct,it is that readers fail to see the relevance of losing the primary fact in all science – that one rotation and one day keep in step.Maybe the human mind simply refuses to accept that anyone would make such a mistake but I assure you all that they did.
Late to the party and It’s possible a Coriolis effect causes the solar mag fields and the sunspots.
2pesos.
Leif Svaalgard,
“No valid critique has been put forward. The article is a progress report on ongoing work. There are two issues:
1) weighting of Zurich/International SSN. This is now established fact
2) calibration of GSN. Anybody can duplicate the analysis using published data.
The actual talk at the conference [with notes] is here
http://www.leif.org/research/Solar-Activity-Past-Present-and-Future-Notes.pdf”
How does it feel to be the purveyor of Consensus Science???
We will be eagerly awaiting your next projections!!!
HAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAH
From Gerald Kelleher on November 13, 2012 at 3:31 pm:
Yes, the chicken knows if it’s a rooster or a hen. I never specified which, so you didn’t know. What hens let out a morning call?
Your comments have been amusing, sometimes perplexing. Now you’re challenging easily verifiable math. Relative to the stars, the Earth takes 23hrs 56min 4sec to return to the same orientation (23.9344 hrs). You could time this yourself in your own backyard.
You see 24hrs because relative to the stars, the Sun has moved position relative to the Earth, it takes another 3min 56sec to “catch up”.
365.25 days/yr * 24hrs/day / 23.9344hrs/rotation
=366.25 rotations.
Here on Earth, watching the Sun, there are 365.25 days to the year, it takes 1461 24-hr periods for the Sun to return to the same spot. But during those 365.25 days, the Earth has turned on it axis 366.25 times relative to the stars.
If you can’t figure out such a basic frame of reference issue, and want to rant about “mistakes” being foisted on the public… Better avoid designing gearing for any machine whatsoever, especially planetary gearing, or you’ll be ranting about mechanical engineers as well.
kadaka (KD Knoebel) says:
November 13, 2012 at 7:35 pm
I agree with your averages, but due to Earth’s elliptical orbit, it is a bit more complicated. : -)
“The shortest days are some 23 hours, 59 minutes and 40 seconds long and occur around 15 September, while the longest days around Christmas are some 24 hours and 3 0 seconds long.
Watches are based on the convenient assumption that all days in the year are exactly 24 hours long. Sundials take the days as they are, varying in length from 24 hours and 30 seconds in late December and 23 hours 59 minutes and 40 seconds on 15 September as stated above.”
See:
http://www.spot-on-sundials.co.uk/noon.html
This was good. Thank you. Leif Svalgaard.
From Werner Brozek on November 13, 2012 at 9:40 pm:
I agree with your averages, but due to Earth’s elliptical orbit, it is a bit more complicated. : -)
And when isn’t it a bit more complicated?
But just like chemists contemplating chemical reactions based on electron shells, or using the small angle approximation with pendulums, you can stay simple and still get the right answer, that’s correct enough.
From me on November 13, 2012 at 7:35 pm:
That’s 366.25 rotations/yr.
Always make sure you have the units right!
days/yr * hrs/day / hrs/rotation
(rewrite to multiply)
=> days/yr * hrs/day * rotations/hr
(cancel days)
=> hrs/yr * rotations/hr
(cancel hrs)
=> rotations/yr.
Solar Activity – Past, Present, Future
Prediction of solar activity has a poor track record, but the progression of the current Cycle 24 is in accordance with its behaviour predicted from the evolution of the solar polar fields, so perhaps there is hope.
The very long cosmic ray record (when calibrated and understood correctly) provides the necessary material for statistical studies of the frequency and features of extremes of solar activity (the ‘500-year floods’). The first order of business is to understand why the variations are discordant compared to other solar indicators the past 400 years. This effort is ongoing and the results are not yet in sight.
Not really, the sight depends on the personal point of view. Astronomical investigations have shown that cosmic ray records are connected to solar tide functions and moreover because of the linearity of the time function of the ‘Julian Day’ definition it can be used for calibrations of the records. And because of this the connection of solar tide functions terrestrial climate functions as global sea level, global temperatures or the cosmic ray function can be calculated forward in high resolution of month > 1000 years into the future.
http://www.volker-doormann.org/images/cosmic_r_vs_solar_tide.jpg
In this graph the astronomic time function is scaled by a factor of 1.15 because it seems that the cosmic ray record time data are not accurate and not linear, and a prediction is plotted for the next 200 years.
It is clear that the frequency of the sun spots and the modulation frequency of 1/centuries cannot give results of cosmic rays from the sun in high time resolution. But oscillations of ~6.3 cycles per year as well in the sea level data and in the temperature data from satellites fit well with solar tide functions of high frequency objects in the solar system of high density.
http://www.volker-doormann.org/images/uah_rss_ghi11_r_oct.gif
http://www.volker-doormann.org/images/hadcrut3_vs_solar_tides.gif
Solar activity means all and nothing. One has to see the stable solar oscillator from its geometry and the frequency modulation and its causes separately. The sun spot time shift or frequency modulation is correlated to the global temperature reconstruction:
http://www.volker-doormann.org/images/sun_shift_buent.gif
Because it is obvious that solar tide functions of ~6.30 periods per year unto 0.0011 periods per year are visible it seems that not the sunspot activity function is relevant but all the relevant solar tide functions and its frequencies.
There is a big title claiming ‘Future’, but I have not found any hard predictions. However, it shows the limit of a heliocentric personal point of view rejecting the frequencies in the whole solar system.
V.
pochas says:
November 13, 2012 at 12:02 pm
The electrons get going faster than the protons, hence the electric current and the orthogonal magnetic field. This is the principle behind magnetohydrodynamics.
From Tokyo [so a bit late]:
Unfortunately that doesn’t quite work. You cannot easily separate electrons from protons because of their very strong mutual attraction. The Biermann Battery Effect very early on in the history of the Universe did create a magnetic field from nothing, but that process is extremely inefficient and has no significance in the Sun.