The Beauty of a Near Spotless Sun

If the polarity is reversed, is it SC23 or 25. Has this happened before?
Does anyone konw?

Mr. Alex says:
June 27, 2010 at 4:52 am
The polarity is reversed! SC 23/25 polarity!
3% of all spots [that is one in about 30] are reversed. This does not mean a SC23 spot [too high latitude for that], and not a Sc25, because that is too far away in time. So, nothing shocking, and NOAA does not the polarity as a reason to not count a spot. They probably didn’t see it [hard so near the limb] or it was not seen by more than one observer, or didn’t meet some of their other criteria [like visible for at least 12 hours].

kim says:
June 27, 2010 at 9:51 am
LeanGate, please.
Judith Lean is a good friend of mine and a good scientist. That the IPCC didn’t involve more scientists on the solar issue is not a negative reflection on Judith. Perhaps it is more a reflection of how much [or how little] the IPCC believe the Sun is important. Lean’s analysis of this subject looks good to me: there is an influence, but it is small [barely detectable – otherwise we would not be discussing it]. The IPCC also did not compose a large team to evaluate the influence of Ceres or Pluto on the Earth…

Andrew30 says:
June 27, 2010 at 7:56 am
Someone needs to be using the same technology today as was used to create the historical record
Everybody is doing just that [except the Layman’s Count]
So who is using the historical method to measure sunspots? It is a trap.
Everybody is.
Charles S. Opalek, PE says:
June 27, 2010 at 8:23 am
For a real eye-opener about the present lack of solar activity
This paper is cyclomanic junk, IMHO. For people that believe in cycles it may be of some comfort, but it is hardly hard science. Now, scientists are often speculating [out of the box] and there is nothing wrong with that, but we should not see such as more than it is.

Mr. Alex says:
June 27, 2010 at 10:43 am
This is my past experience, and it is not the first time that this hesitation has happened with a reverse polarity sunspot.
I don’t think this is the case [I know the people at NOAA and how they count – reversed polarity does not create ‘hesitation’]. To bolster your claim, produce a list of cases.
however some folks on other blogs (Italian) believe that the number of RP spots in this cycle have exceeded 3%…
Again, the way to settle this is to produce a list. When SC23 ‘ended’ the NOAA region count was 11008. Now it is 11084, for a difference of 72. 3% of that is 2 spots, so statistically we should have had 2 reversed spots [and with so few spots that could easily be 1 or 3 as well]. Now, we need to be more precise: we should talk about the active ‘region’ rather than of individual spots. It is only with respect to the region of several spots [some leading and some trailing] that ‘reversed’ polarity makes sense. If what you got is a single spot, you can’t tell if it is reversed. You can tell whether the region is, and 1084 is.
the spot has STILL not been numbered.
1084

kim says:
June 27, 2010 at 11:17 am
Leif, if the allegations about Froelich are correct, how can Lean’s analysis be ‘fair’?
‘allegations’ are misplaced. Every experimenter adjust the data. The problem is that the detectors degrade in the harsh environment of space being in vacuum exposed to X-rays, UV, solar wind, cosmic rays, etc. The degradation is much larger than the solar changes in TSI and must be measured [estimated is a better word – ‘guessed at’ some would say]. One way is to have several detectors exposed different lengths of time, then look at the degradation of a function of time ans extrapolate to zero time.
There are disagreements about what the degradations are and how to employ them, but all that and the ‘JudithGate’ are just strawmen in the question about solar influence, because the final adjusted datasets do actually not disagree very much.

Leif Svalgaard says:
June 27, 2010 at 1:15 pm
Correction, of course:
Using the ACRIM data instead of Fröhlich’s makes no difference to the analysis except increasing the noise and hence decreasing the statistical significance of any solar connection.

Hockey Schtick says:
June 27, 2010 at 12:42 pm
incorrect adjustments
You can learn more about these issues here:
http://lasp.colorado.edu/sorce/news/2010ScienceMeeting/doc/Session1/1.07_Dewitte_TSI.pdf
ACRIM is clearly the odd man out.

Policyguy says:
June 27, 2010 at 1:36 pm
Forthcoming Grand Minima, but relies on an entirely different method to get there: C-14 dating of tree rings.
Their conclusion:
“However, our carbon-14 based observations do not indicate the imminent occurrence of the Maunder Minimum”
They also invoke Livingston&Penn as a possible explanation for the lack of visible sunspots during the Maunder [and I tend to agree with that] while at the same time there was a solar modulation of cosmic rays.

too many typos, here is a better one:
Policyguy says:
June 27, 2010 at 2:11 pm
It relies on solar physics to reach the authors’ conclusions. […]
http://journalofcosmology.com/ClimateChange111.html (Duhua and de Jager
It may look like solar physics [and de Jager used to be a highly respected solar physicist], but it smacks too much of ‘cyclomania’ for my taste. People have been looking for cycles ever since Schwabe discovered his, but with little success [despite the many claims – pick any number at random and there will be someone claiming a solar periodicity close the that 🙂 ]. Careful analysis of solar proxies going back some 12,000 years shows that grand minima do not have a periodicity to them.
Now, I won’t disagree with the next cycle being weak, but one has to be correct for the right reasons.

tallbloke says:
June 27, 2010 at 3:02 pm
The Sun’s influence on climate variation is dominant. There are clear lines of evidence to support this assertion.
Actually not. See: http://www.leif.org/research/Does%20The%20Sun%20Vary%20Enough.pdf slide 20 says in all. The arguments that TSI is not the whole story are tired. TSI and all the other solar variables vary much in unison because of the same underlying cause: the solar magnetic field.
‘Dominant’ is a big word. Care to quantify that? Otherwise you can say it with real meaning other than hand waving [which seems to be enough for some people].
Once clouds are also factored in, the link between the Sun and climate variation is pretty clear
Gee, yes. When it is cloudy it is less hot [lemme see if I can find a handy reference to that… hmm, here is one http://www.chicagobreakingnews.com/2010/03/weekend-weather-cloudy-wet-windy-and-cool.html ]

Hockey Schtick says:
June 27, 2010 at 2:26 pm
My only “agenda” is to find the truth. Interesting that you feel I’m biased
Indeed.
Willson is biased, Hoyt is biased, D’Aleo is biased, Scafetta is biased…
I don’t think they are biased the same way as you are, just wrong.
Also interesting that after you point out all the potential uncertainties and various interpretations of the TSI data, that it doesn’t seem to bother you
These uncertainties are much smaller than the solar variations and therefore have little or no influence on Lean’s assessment.
more balanced presentation incorporating alternative views.
Science not ‘views’ than can be voted on, resolved by consensus, or be more or less ‘balanced’. In fact, science should be as start and unbalanced as possible.
Also interesting in light of the fact that multiple recent findings show the “solar constant” is not so constant and the sun is much more variable than previously thought.
No, less variable. When the ‘solar constant’ was first reasonably well measured [e.g. http://www.leif.org/EOS/Abbot-Variation-Sun.pdf%5D in the first decade of the 20th century the variations were cited to be about 50 w/m2 or 10-25 times larger than what we find today.
Also interesting that proxies of solar activity have found the sun to be more active in the 20th century than over the past 8000 years
That is very likely not so, see e.g. http://www.leif.org/EOS/muscheler05nat_nature04045.pdf
“our reconstruction indicates that solar activity around AD 1150 and 1600 and in the late eighteenth century was probably comparable to the recent satellite-based observations.”
or
http://www.leif.org/EOS/2009GL038004.pdf
“Recent 10Be values are low; however, they do not indicate unusually high recent solar activity compared to the last 600 years.”
There are many myths out there that masquerade as ‘truths’ or are labeled as such by people with agendas.

tallbloke says:
June 27, 2010 at 5:02 pm
On the contrary Leif, it your argument that TSI is the whole story that is tired. Some of your solar physics is good, but your approach to climatology is rubbish.
A good test of a theory is prediction, so calculate the temperature from your model for the past 10,000 years. This should be possible [indeed easy] as all input variables seem to depend only on planetary positions. BTW, one cannot have an ‘approach’ to science. It is either done right or not.
Your use of a weather repost to dismiss Soon et al’s graph showing a correlation between sunshine hours and surface temperature at the centennial timescale is just laughable.
fits with the general strength of your argument, which is indeed laughable. Soon’s argument is circular.

phlogiston says:
June 27, 2010 at 5:30 pm
“The problem is that the detectors degrade in the harsh environment of space being in vacuum exposed to X-rays, UV, solar wind, cosmic rays, etc.”
Why then are satellite measurements of temperature, or of anything, taken seriously by anyone?
Both measurements are taken seriously, but they are completely different in nature. For TSI which we measure MUCH more precisely than temperatures in the atmosphere we keep track of the degradation. Here is how it is done:
http://lasp.colorado.edu/sorce/news/2010ScienceMeeting/doc/Session1/1.07_Dewitte_TSI.pdf
We measure TSI with a precision of 0.0068 W/m2 which is 1,000,000*0.0068/1361 = 5 parts in a million, or comparable to 10 feet of the distance between L.A. and S.F.
Tallbloke
About Soon’s graph linking Japanese sun time with China temperature: is this not just a reflection of cloud cover? No need for any solar variation to explain this figure.
Agree, as I said, when it is cloudy, it is cooler. Or in this particular case: cold weather over China means clouds, and those clouds move generally eastwards towards Japan.
Leif Svalgaard
“solar activity around AD 1150 and 1600 and in the late eighteenth century was probably comparable to the recent satellite-based observations.”
Am I right in assuming this is your explanation for the medieval warm period?
No, as first: there is little, if any influence by the sun on the climate, and second, 1600th and the 18th century were not part of the MWP, or any other warm period.
Jeff says:
June 27, 2010 at 5:36 pm
recent uptick in solar activity might be due to just a couple of active regions that survive more than one solar rotation.
Yes, not much to crow about.
It ought to be possible, using the SOHO backside models and the Stereo images, to follow active regions all the way around. Has anybody done that for the recent spot groups?
People do this kind of thing. Some try even to ‘see’ through the Sun. Not much have come of this.

tallbloke says:
June 27, 2010 at 6:14 pm
The ability to miss the point or desire to deliberately obscure it. Which is it I wonder.
How about the point being dubious to begin with?

Geoff Sharp says:
June 27, 2010 at 7:03 pm
The new region has now evolved into to a reversed polarity group for SC24 and is noted for is large size amongst previous reversed regions.
Regions rotate and for that reason if they live long enough might end up ‘reversed’. this is normal and is not a sign of SC24 ending, SC25 or SC27 or any such making an appearance. [I know you don’t make such claims, but others do]
Question: What effect do these reversed regions have on the migrating reversing poleward flux.
Not much as only 1/1000th of the flux makes it to the poles, so an occasional reversed spot won’t have much impact.
If there is a diminishing effect they could be responsible for the south not reversing polarity this maximum?
Hardly, as we can easily miss 30 out of a 1000 spots not making it to the poles.
Now, if more than 50% of spots were reversed, that would be significant. But such is not the case.
This along with Hathaway’s observation of the very slow conveyor belt (base) in the south make this hemisphere most interesting to watch.
‘very slow’ is relative. It normally takes about 1000,000,000[m]/15[m/s] ~ 2 years to reach the pole. should that be 4 years instead, just means that the cycle will be bit longer, which we expect anyway.
rbateman’s sunspot area graphs telling the true picture for SC24.
The true picture is given by the F10.7 flux.

David44 says:
June 27, 2010 at 7:28 pm
Leif Svalgaard says @ June 27, 2010 at 6:05 pm
“…there is little, if any influence by the sun on the climate…”
To a novice such as my self, that sounds crazy. Do you mean it literally, or something more like: “the very small variations in solar output that we measure have little or no influence on variations in climate” ?
Clearly the latter.

Nasif Nahle says:
June 27, 2010 at 8:04 pm
The question is: Which one of the three is the most accurate, non biased reconstruction?
The latest one. And there is no bias here anymore. It was once thought that there was a long-term varying background approximately controlled by the 11-year running mean of the sunspot number. This ‘bias’ was partly motivated by the desire to account for the LIA [otherwise the variation in TSI would clearly be too small]. Lean’s and others [including yours truly] later research have undermined that idea, and nobody [except die-hard solar enthusiasts] believes anymore that there is such a background. Hence the almost flat curve.

Teh JC says:
June 27, 2010 at 8:58 pm
if the sun is asleep, so-to-speak, what is making it sleep?
It goes to sleep every eleven years.
Contrary to old school belief, the sun does not have a hydrogen core; it is high dense iron.
No, the old school is still correct. The iron core is plain nonsense.
James F. Evans says:
June 27, 2010 at 8:59 pm
Another cold northern hemisphere winter and those with the “sun doesn’t matter” position will be harder pressed to maintain that same position.
You mean when we approach solar maximum? And “harder pressed” by whom?
I seem to recall that the last several months of very low solar activity all had record-high temperatures. Perhaps caused by the recent tiny uptick in solar activity?

mikelorrey says:
June 27, 2010 at 9:12 pm
I find the past several months data on both sunspot and 10.7 to have remained significantly below (50% or more) predicted levels.
Remember that the ‘predicted’ levels were too high to begin with [a max around 70 seems more reasonable].
At this point in time we should be seeing monthly escalating levels of both as SC24 explodes in activity.
‘explodes’ is perhaps a bit too much to hope for. Also, as you know I think the sunspot number is too low by about a factor of two [Livingston&Penn – http://www.leif.org/research/Solar-Microwaves-at-23-24-Minimum.pdf ]. The flux is on its way up, albeit in fists and starts: http://www.leif.org/research/F107%20at%20Minima%201954%20and%202008.png
Note that the blue curve touched the red [coming out of the 1954 minimum into one of the biggest cycles ever], so give it a bit a time.

David44 says:
June 27, 2010 at 11:50 pm
Is it your understanding then, Dr. Svalgaard, that because of the ACRIM controversy, Lean and colleagues have or would today today recant their 1997 JGR paper
Not at all. The ACRIM controversy has nothing to do with this. First, it is very small [fractions of a Watt/m2, second]; second, her statement “the observed rise in solar irradiance of approximately 2.0 W m-2 at the top of the atmosphere” is not correct and conclusions based on that are therefore suspect.
We have all learned something the past 13 years, and one thing we have learned is that there has very likely not been such a large increase. Lean today would agree with this.

Hockey Schtick says:
June 27, 2010 at 11:38 pm
It’s apparently ok with Dr. Svalgaard if the IPCC chooses one solar physicist to feature her own paper as an implied balanced consensus – without mentioning alternative views or any controversies regarding the way her data was adjusted – ok got it.
Your bias shows in the way you uncritically parrot the JudithGate nonsense without actually knowing what IPCC said in their AR4.
Here is a sample:
2.7.1 Solar Variability
“The estimates of long-term solar irradiance changes used in the TAR (e.g., Hoyt and Schatten, 1993; Lean et al., 1995) have been revised downwards, based on new studies indicating that bright solar faculae likely contributed a smaller irradiance increase since the Maunder Minimum than was originally suggested by the range of brightness in Sun-like stars (Hall and Lockwood, 2004; M. Wang et al., 2005). However, empirical results since the TAR have strengthened the evidence for solar forcing of climate change by identifying detectable tropospheric changes associated with solar variability, including during the solar cycle (Section 9.2; van Loon and Shea, 2000; Douglass and Clader, 2002; Gleisner and Thejll, 2003; Haigh, 2003; Stott et al., 2003; White et al., 2003; Coughlin and Tung, 2004; Labitzke, 2004; Crooks and Gray, 2005). The most likely mechanism is considered to be some combination of direct forcing by changes in total solar irradiance, and indirect effects of ultraviolet (UV) radiation on the stratosphere. Least certain, and under ongoing debate as discussed in the TAR, are indirect effects induced by galactic cosmic rays (e.g., Marsh and Svensmark, 2000a,b; Kristjánsson et al., 2002; Sun and Bradley, 2002).
2.7.1.1.1 Satellite measurements of total solar irradiance
Four independent space-based instruments directly measure total solar irradiance at present, contributing to a database extant since November 1978 (Fröhlich and Lean, 2004). The Variability of Irradiance and Gravity Oscillations (VIRGO) experiment on the Solar Heliospheric Observatory (SOHO) has been operating since 1996, the ACRIM III on the Active Cavity Radiometer Irradiance Monitor Satellite (ACRIMSAT) since 1999 and the Earth Radiation Budget Satellite (ERBS) (intermittently) since 1984. Most recent are the measurements made by the Total Solar Irradiance Monitor (TIM) on the Solar Radiation and Climate Experiment (SORCE) since 2003 (Rottman, 2005).
2.7.1.1.2 Observed decadal trends and variability
Different composite records of total solar irradiance have been constructed from different combinations of the direct radiometric measurements. The Physikalisch-Meteorologisches Observatorium Davos (PMOD) composite (Fröhlich and Lean, 2004), shown in Figure 2.16, combines the observations by the ACRIM I on the Solar Maximum Mission (SMM), the Hickey-Friedan radiometer on Nimbus 7, ACRIM II on the Upper Atmosphere Research Satellite (UARS) and VIRGO on SOHO by analysing the sensitivity drifts in each radiometer prior to determining radiometric offsets. In contrast, the ACRIM composite (Willson and Mordvinov, 2003), also shown in Figure 2.16, utilises ACRIMSAT rather than VIRGO observations in recent times and cross calibrates the reported data assuming that radiometric sensitivity drifts have already been fully accounted for. A third composite, the Space Absolute Radiometric Reference (SARR) composite, uses individual absolute irradiance measurements from the shuttle to cross calibrate satellite records (Dewitte et al., 2005). The gross temporal features of the composite irradiance records are very similar, each showing day-to-week variations associated with the Sun’s rotation on its axis, and decadal fluctuations arising from the 11-year solar activity cycle. But the linear slopes differ among the three different composite records, as do levels at solar activity minima (1986 and 1996). These differences are the result of different cross calibrations and drift adjustments applied to individual radiometric sensitivities when constructing the composites (Fröhlich and Lean, 2004).
Figure 2.16. Percentage change in monthly values of the total solar irradiance composites of Willson and Mordvinov (2003; WM2003, violet symbols and line) and Fröhlich and Lean (2004; FL2004, green solid line). 
Solar irradiance levels are comparable in the two most recent cycle minima when absolute uncertainties and sensitivity drifts in the measurements are assessed (Fröhlich and Lean, 2004 and references therein). The increase in excess of 0.04% over the 27-year period of the ACRIM irradiance composite (Willson and Mordvinov, 2003), although incompletely understood, is thought to be more of instrumental rather than solar origin (Fröhlich and Lean, 2004). The irradiance increase in the ACRIM composite is indicative of an episodic increase between 1989 and 1992 that is present in the Nimbus 7 data (Lee et al., 1995; Chapman et al., 1996). Independent, overlapping ERBS observations do not show this increase; nor do they suggest a significant secular trend (Lee et al., 1995). Such a trend is not present in the PMOD composite, in which total irradiance between successive solar minima is nearly constant, to better than 0.01% (Fröhlich and Lean, 2004). Although a long-term trend of order 0.01% is present in the SARR composite between successive solar activity minima (in 1986 and 1996), it is not statistically significant because the estimated uncertainty is ±0.026% (Dewitte et al., 2005).
Current understanding of solar activity and the known sources of irradiance variability suggests comparable irradiance levels during the past two solar minima. The primary known cause of contemporary irradiance variability is the presence on the Sun’s disk of sunspots (compact, dark features where radiation is locally depleted) and faculae (extended bright features where radiation is locally enhanced). Models that combine records of the global sunspot darkening calculated directly from white light images and the magnesium (Mg) irradiance index as a proxy for the facular signal do not exhibit a significant secular trend during activity minima (Fröhlich and Lean, 2004; Preminger and Walton, 2005). Nor do the modern instrumental measurements of galactic cosmic rays, 10.7 cm flux and the aa geomagnetic index since the 1950s (Benestad, 2005) indicate this feature. While changes in surface emissivity by magnetic sunspot and facular regions are, from a theoretical view, the most effective in altering irradiance (Spruit, 2000), other mechanisms have also been proposed that may cause additional, possibly secular, irradiance changes. Of these, changes in solar diameter have been considered a likely candidate (e.g., Sofia and Li, 2001). But recent analysis of solar imagery, primarily from the Michelson Doppler Imager (MDI) instrument on SOHO, indicates that solar diameter changes are no more than a few kilometres per year during the solar cycle (Dziembowski et al., 2001), for which associated irradiance changes are 0.001%, two orders of magnitude less than the measured solar irradiance cycle.
2.7.1.2.1 Reconstructions of past variations in solar irradiance
Long-term solar irradiance changes over the past 400 years may be less by a factor of two to four than in the reconstructions employed by the TAR for climate change simulations. Irradiance reconstructions such as those of Hoyt and Schatten (1993), Lean et al. (1995), Lean (2000), Lockwood and Stamper (1999) and Solanki and Fligge (1999), used in the TAR, assumed the existence of a long-term variability component in addition to the known 11-year cycle, in which the 17th-century Maunder Minimum total irradiance was reduced in the range of 0.15% to 0.3% below contemporary solar minima. The temporal structure of this long-term component, typically associated with facular evolution, was assumed to track either the smoothed amplitude of the solar activity cycle or the cycle length. The motivation for adopting a long-term irradiance component was three-fold. Firstly, the range of variability in Sun-like stars (Baliunas and Jastrow, 1990), secondly, the long-term trend in geomagnetic activity, and thirdly, solar modulation of cosmogenic isotopes, all suggested that the Sun is capable of a broader range of activity than witnessed during recent solar cycles (i.e., the observational record in Figure 2.16). Various estimates of the increase in total solar irradiance from the 17th-century Maunder Minimum to the current activity minima from these irradiance reconstructions are compared with recent results in Table 2.10.
Each of the above three assumptions for the existence of a significant long-term irradiance component is now questionable. A reassessment of the stellar data was unable to recover the original bimodal separation of lower calcium (Ca) emission in non-cycling stars (assumed to be in Maunder-Minimum type states) compared with higher emission in cycling stars (Hall and Lockwood, 2004), which underpins the Lean et al. (1995) and Lean (2000) irradiance reconstructions. Rather, the current Sun is thought to have ‘typical’ (rather than high) activity relative to other stars. Plausible lowest brightness levels inferred from stellar observations are higher than the peak of the lower mode of the initial distribution of Baliunas and Jastrow (1990). Other studies raise the possibility of long-term instrumental drifts in historical indices of geomagnetic activity (Svalgaard et al., 2004), which would reduce somewhat the long-term trend in the Lockwood and Stamper (1999) irradiance reconstruction. Furthermore, the relationship between solar irradiance and geomagnetic and cosmogenic indices is complex, and not necessarily linear. Simulations of the transport of magnetic flux on the Sun and propagation of open flux into the heliosphere indicate that ‘open’ magnetic flux (which modulates geomagnetic activity and cosmogenic isotopes) can accumulate on inter-cycle time scales even when closed flux (such as in sunspots and faculae) does not (Lean et al., 2002; Y. Wang et al., 2005).
A new reconstruction of solar irradiance based on a model of solar magnetic flux variations (Y. Wang et al., 2005), which does not invoke geomagnetic, cosmogenic or stellar proxies, suggests that the amplitude of the background component is significantly less than previously assumed, specifically 0.27 times that of Lean (2000). This estimate results from simulations of the eruption, transport and accumulation of magnetic flux during the past 300 years using a flux transport model with variable meridional flow. Variations in both the total flux and in just the flux that extends into the heliosphere (the open flux) are estimated, arising from the deposition of bipolar magnetic regions (active regions) and smaller-scale bright features (ephemeral regions) on the Sun’s surface in strengths and numbers proportional to the sunspot number. The open flux compares reasonably well with the cosmogenic isotopes for which variations arise, in part, from heliospheric modulation. This gives confidence that the approach is plausible. A small accumulation of total flux (and possibly ephemeral regions) produces a net increase in facular brightness, which, in combination with sunspot blocking, permits the reconstruction of total solar irradiance shown in Figure 2.17. There is a 0.04% increase from the Maunder Minimum to present-day cycle minima.
Prior to direct telescopic measurements of sunspots, which commenced around 1610, knowledge of solar activity is inferred indirectly from the 14C and 10Be cosmogenic isotope records in tree rings and ice cores, respectively, which exhibit solar-related cycles near 90, 200 and 2,300 years. Some studies of cosmogenic isotopes (Jirikowic and Damon, 1994) and spectral analysis of the sunspot record (Rigozo et al., 2001) suggest that solar activity during the 12th-century Medieval Solar Maximum was comparable to the present Modern Solar Maximum. Recent work attempts to account for the chain of physical processes in which solar magnetic fields modulate the heliosphere, in turn altering the penetration of the galactic cosmic rays, the flux of which produces the cosmogenic isotopes that are subsequently deposited in the terrestrial system following additional transport and chemical processes. An initial effort reported exceptionally high levels of solar activity in the past 70 years, relative to the preceding 8,000 years (Solanki et al., 2004). In contrast, when differences among isotopes records are taken into account and the 14C record corrected for fossil fuel burning, current levels of solar activity are found to be historically high, but not exceptionally so (Muscheler et al., 2007).
2.7.1.2.2 Implications for solar radiative forcing
In terms of plausible physical understanding, the most likely secular increase in total irradiance from the Maunder Minimum to current cycle minima is 0.04% (an irradiance increase of roughly 0.5 W m–2 in 1,365 W m–2), corresponding to an RF[11] of +0.1 W m–2. The larger RF estimates in Table 2.10, in the range of +0.38 to +0.68 W m–2, correspond to assumed changes in solar irradiance at cycle minima derived from brightness fluctuations in Sun-like stars that are no longer valid. Since the 11-year cycle amplitude has increased from the Maunder Minimum to the present, the total irradiance increase to the present-day cycle mean is 0.08%. From 1750 to the present there was a net 0.05% increase in total solar irradiance, according to the 11-year smoothed total solar irradiance time series of Y. Wang et al. (2005), shown in Figure 2.17. This corresponds to an RF of +0.12 W m–2, which is more than a factor of two less than the solar RF estimate in the TAR, also from 1750 to the present. Using the Lean (2000) reconstruction (the lower envelope in Figure 2.17) as an upper limit, there is a 0.12% irradiance increase since 1750, for which the RF is +0.3 W m–2. The lower limit of the irradiance increase from 1750 to the present is 0.026% due to the increase in the 11-year cycle only. The corresponding lower limit of the RF is +0.06 W m–2. As with solar cycle changes, long-term irradiance variations are expected to have significant spectral dependence. For example, the Y. Wang et al. (2005) flux transport estimates imply decreases during the Maunder Minimum relative to contemporary activity cycle minima of 0.43% at 200 to 300 nm, 0.1% at 315 to 400 nm, 0.05% at 400 to 700 nm, 0.03% at 700 to 1,000 nm and 0.02% at 1,000 to 1,600 nm (Lean et al., 2005), compared with 1.4%, 0.32%, 0.17%, 0.1% and 0.06%, respectively, in the earlier model of Lean (2000).
Table 2.10. Comparison of the estimates of the increase in RF from the 17th-century Maunder Minimum (MM) to contemporary solar minima, documenting new understanding since the TAR.
Reference Assumptions and Technique RF Increase from the Maunder Minimum to Contemporary Minima (W m–2)a Comment on Current Understanding
Schatten and Orosz (1990) Extrapolation of the 11-year irradiance cycle to the MM, using the sunspot record. ~ 0 Irradiance levels at cycle minima remain approximately constant.
Lean et al. (1992) No spots, plage or network in Ca images assumed during MM. 0.26 Maximum irradiance increase from a non-magnetic sun, due to changes in known bright features on contemporary solar disk.
Lean et al. (1992) No spots, plage or network and reduced basal emission in cell centres in Ca images to match reduced brightness in non-cycling stars, assumed to be MM analogues. 0.45 New assessment of stellar data (Hall and Lockwood, 2004) does not support original stellar brightness distribution, or the use of the brightness reduction in the Baliunas and Jastrow (1990) ‘non-cycling’ stars as MM analogues.
Hoyt and Schatten (1993)b Convective restructuring implied by changes in sunspot umbra/penumbra ratios from MM to present: amplitude of increase from MM to present based on brightness of non-cycling stars, from Lean et al. (1992). 0.65 As above
Lean et al. (1995) Reduced brightness of non-cycling stars, relative to those with active cycles, assumed typical of MM. 0.45 As above
Solanki and Fligge (1999)b Combinations of above. 0.68 As above
Lean (2000) Reduced brightness of non-cycling stars (revised solar-stellar calibration) assumed typical of MM. 0.38 As above
Foster (2004) Model Non-magnetic sun estimates by removing bright features from MDI images assumed for MM. 0.28 Similar approach to removal of spots, plage and network by Lean et al. (1992).
Y. Wang et al. (2005)b Flux transport simulations of total magnetic flux evolution from MM to present. 0.1 Solar model suggests that modest accumulation of magnetic flux from one solar cycle to the next produces a modest increase in irradiance levels at solar cycle minima.
Dziembowski et al. (2001) Helioseismic observations of solar interior oscillations suggest that the historical Sun could not have been any dimmer than current activity minima. ~ 0
Notes:
a The RF is the irradiance change divided by 4 (geometry) and multiplied by 0.7 (albedo). The solar activity cycle, which was negligible during the Maunder Minimum and is of order 1 W m–2 (minimum to maximum) during recent cycles, is superimposed on the irradiance changes at cycle minima. When smoothed over 20 years, this cycle increases the net RF in the table by an additional 0.09 W m–2.
b These reconstructions extend only to 1713, the end of the Maunder Minimum.
Figure 2.17. Reconstructions of the total solar irradiance time series starting as early as 1600. The upper envelope of the shaded regions shows irradiance variations arising from the 11-year activity cycle. The lower envelope is the total irradiance reconstructed by Lean (2000), in which the long-term trend was inferred from brightness changes in Sun-like stars. In comparison, the recent reconstruction of Y. Wang et al. (2005) is based on solar considerations alone, using a flux transport model to simulate the long-term evolution of the closed flux that generates bright faculae.
—————–
And so on and on…

Hockey Schtick says:
June 27, 2010 at 11:38 pm
It’s apparently ok with Dr. Svalgaard if the IPCC chooses one solar physicist to feature her own paper
Is even wrong on its face. Here are the authors. I have highlighted the ones I know are solar or space physicists [there are, of course, only one lead author for each subject.
Coordinating Lead Authors:
Piers Forster (UK), Venkatachalam Ramaswamy (USA)
Lead Authors:
Paulo Artaxo (Brazil), Terje Berntsen (Norway), Richard Betts (UK), David W. Fahey (USA), James Haywood (UK), Judith Lean (USA), David C. Lowe (New Zealand), Gunnar Myhre (Norway), John Nganga (Kenya), Ronald Prinn (USA, New Zealand), Graciela Raga (Mexico, Argentina), Michael Schulz (France, Germany), Robert Van Dorland (Netherlands)
Contributing Authors:
G. Bodeker (New Zealand), O. Boucher (UK, France), W.D. Collins (USA), T.J. Conway (USA), E. Dlugokencky (USA), J.W. Elkins (USA),
D. Etheridge (Australia), P. Foukal (USA), P. Fraser (Australia), M. Geller (USA), F. Joos (Switzerland), C.D. Keeling (USA), R. Keeling (USA), S. Kinne (Germany), K. Lassey (New Zealand), U. Lohmann (Switzerland), A.C. Manning (UK, New Zealand), S. Montzka (USA),
D. Oram (UK), K. O’Shaughnessy (New Zealand), S. Piper (USA), G.-K. Plattner (Switzerland), M. Ponater (Germany),
N. Ramankutty (USA, India), G. Reid (USA), D. Rind (USA), K. Rosenlof (USA), R. Sausen (Germany), D. Schwarzkopf (USA),
S.K. Solanki (Germany, Switzerland), G. Stenchikov (USA), N. Stuber (UK, Germany), T. Takemura (Japan), C. Textor (France, Germany),
R. Wang (USA), R. Weiss (USA), T. Whorf (USA)
—–
I may have missed some [got tired], but you should get that there were many solar physicists as authors.

Hockey Schtick says:
June 28, 2010 at 1:15 am
how can you state that “the adjustments are so small…”?
Because a third is only 1/4 of the usual solar cycle variation [which we can barely see in the temperature response] or about 0.02K. We cannot even measure a 0.02K change.

Here is what an active Sun looks like:
ftp://howard.astro.ucla.edu/pub/obs/drawings/1957/dr570102.jpg
ftp://howard.astro.ucla.edu/pub/obs/drawings/1957/dr570623.jpg
ftp://howard.astro.ucla.edu/pub/obs/drawings/1957/dr571223.jpg
ftp://howard.astro.ucla.edu/pub/obs/drawings/2001/dr010328.jpg
All the little specks and dots must be counted. How many do you find for each of the four drawings? Number of groups and number of spot, specks, and dots.

Leif:
No, the old school is still correct. The iron core is plain nonsense.
The Sun was derived from the same source material as the rest of the Solar System, and as such it surely must have an iron and silicate core (did the heavier elements just propel themselves away from the Sun?). Now that heavy-element core may be minute in comparison to the great bulk of the lighter elements, but a small heavy-element core must be there somewhere, surely.
And another thing that puzzles me. The center of the Sun has no gravity, or even a gravity gradient pulling away from the very center (for an atom at the center of the Sun, the center of mass and therefore center of gravity is actually outwards). If so, then surely the small outwards gravity gradient may even generate a small void at the center of the Sun.
.

I’ve done a month by month analysis of 300 year record of CET temperatures (1700-2000). My conclusion may be speculative, but probably makes more sense than some of IPCC nonsense.
During summer months CET’s directly respond to solar irradiation, while for the rest of the year the Gulf Stream is predominant, with the amount of heat transported as a function of the solar irradiance, with much smaller annual variability in tropics, where the heat is absorbed.
Flow intensity of saline warm waters of the Gulf Stream is modulated by long-term changes in the intensity of the Earth’s magnetic field. These changes in the velocity of the transport system (by the GMF) introduce a variable time delay, directly affecting correlation of the CETs either to the solar irradiance or the Earth’s magnetic field.
Effect of the GMF on saline currents is most clearly shown in correlation to the Arctic temperatures, where the GMF is strongest and consequently the most effective.
http://www.vukcevic.talktalk.net/NFC1.htm

geronimo says:
June 28, 2010 at 4:42 am
bad practice to make a scientist a lead author and then use their paper, and their paper only, to deal with the issue of TSI?
I think I just showed that many papers were cited. Perhaps check out what was actually said.

Leif Svalgaard says:
Vukcevic: Flow intensity of saline warm waters of the Gulf Stream is modulated by long-term changes in the intensity of the Earth’s magnetic field.
Svalgard: No, it is not. The forces involved are too minute to have any effect.
Even an omni-logos can be erroneous.
1895 -“Heavier-than-air flying machines are impossible.” — Lord Kelvin, British mathematician and physicist, president of the British Royal Society.
1903.- Orville Wright took the Flyer for a 12-second sustained flight.
Forces acting on a molecule of water are minute, but not negligible, eventually creating powerful ocean current.
Forces acting on a moving (by the above force) ion of saline water are also minute, but not negligible. Action along length of thousands of miles affects the velocity of the current.
http://envisat.esa.int/live/lg_03.gif

tallbloke says:
June 28, 2010 at 9:43 am
Leif verified my calcs
Of the trivial stuff. The important point is how you connect the things.
As I said:
“A good test of a theory is prediction, so calculate the temperature from your model for the past 10,000 years. This should be possible [indeed easy] as all input variables seem to depend only on planetary positions.”
Do this and come back and show us.
vukcevic says:
June 28, 2010 at 8:32 am
Forces acting on a moving (by the above force) ion of saline water are also minute, but not negligible. Action along length of thousands of miles affects the velocity of the current.
You are an engineer. Calculate the force and convince yourself that it is negligible.

David44 says:
June 28, 2010 at 12:59 pm
Clearly this view conflicts with other investigators who find a clear historical correlation between solar variation and climate changes
There is no doubt that solar activity influences the climate. Everybody I know agrees with that. The sole question is ‘how much’. There is observational evidence that the amount is of the order of a tenth of a degree. This is much less than the changes that most scientists would say we have observed the past few hundred years, so the variability of the Sun is not a dominant or even significant driver of climate. I wish it were as that would make field of study that more important and ensure funding for decades to come.
Do you discount the supposed historical correlation
The correlations are poor and not convincing.
then there must either be an unknown TSI multiplier (cosmic rays or whatever) or an unknown confounder linked to both TSI and climate. No?
Since the correlations are so poor, there does not seem to be good reasons to invoke unknown factors.

James F. Evans says:
June 28, 2010 at 1:47 pm
Yet, at the same time, Dr. Svalgaard regularly refers to his “own” cycles as a means of prediction, interpretation & explanation.
Cycles are not used for anything. We make the prediction a few years ahead of time by observing the polar fields.
Ryan Welch says:
June 28, 2010 at 3:11 pm
in what way can you compare the 1954 Minima of 19/20 to the cycle 23/24?
You compare them by plotting them on the same graph, like you compare thing A with thing B by putting them next to one another and observing them carefully.
The downslope of 23 is nothing like the downslope of 19 and neither is the duration of the Minima.
What you see is that the downslope of 18 [not 19 – that is the upslope] was steeper than 23, because 18 was a much higher cycle [as simple as that]. The duration of the minima were pretty much the same: about 0.6 years on either side of the minimum point [near 2009.0]. The upslope of 24 is much weaker than the upslope of 19, which is one of the signs that our prediction of ‘the smallest cycle in 100 years’ is on track and may even come true.

Leif:
Even Newton knew that there is no gravity inside a spherical shell of matter [ http://hyperphysics.phy-astr.gsu.edu/hbase/mechanics/sphshell2.html ], so the atom does not feel any force from what is further away from the center of the Sun than it is, but only from matter that is closer to the center of the Sun than it is.
Sorry, Leif, the link you gave says that:
“”The net gravitational force on a mass anywhere inside a uniform shell of mass is zero.””
http://hyperphysics.phy-astr.gsu.edu/hbase/mechanics/sphshell2.html
Clearly this is wrong, as I have been 2000′ under the Earth (well inside a spherical shell of mass) and I can assure you that I was not weightless (I was in a deep mine, and walking on the floor in the normal manner). Likewise, drill bits down some 10km inside the Earth are not weightless. Also, as I understand it, convection currents (as present inside the Earth and Sun) can only occur in the presence of a gravity gradient, and not in a weightlessness environment. Thus the weight of a mass inside a sphere of mass HAS to be proportional in some sense to its distance from the center of that sphere.
Anyway, I think we both concur that an atom at the very center of the Sun is weightless, with equal gravitational mass on all sides. But my suggestion is that if a small void develops at the very center of the Sun, then the presence of that void will cause an asymmetry to the gravity gradient that will sustain and perpetuate that void, so it becomes a permanent feature.
.

Ralph says:
June 28, 2010 at 6:20 pm
Clearly this is wrong, as I have been 2000′ under the Earth (well inside a spherical shell of mass)
You were not weightless because there is still 20904000′ below you and you were feeling the force of the mass below you.
oneuniverse says:
June 28, 2010 at 4:18 pm
any reasoning presented to explain why the Voyager measurements should provide an upper bound for past CR LIS. Is there any evidence or argument in support of the assumption?
Voyager is outside the termination shock and has measured the Proton and Helium nuclii spectra. And from those the LIS can be estimated. The detailed reasoning is given in their paper http://www.leif.org/EOS/2009JA014532.pdf to which I refer.
Their conclusion is that the maximum possible 10Be production is only 1.5 times the production at recent solar minima. And that therefore the significantly higher concentrations measured during the Maunder Minimum are most likely not solely related to changes in the sun but that other effects such as local and regional climate near the deposition sites may play a significant role in 10Be concentrations.

oneuniverse says:
June 28, 2010 at 4:18 pm
Sorry, wrong paper. Here is the pertinent one:
ttp://www.leif.org/EOS/2008JA013689.pdf
to which I refer.

tallbloke says:
June 29, 2010 at 7:13 am
So what do you believe to be the correct max figure for the little ice age/Maunder minimum, and where can I download the 10Be data so I can look for myself?
It is not that simple. There is no ’10Be data’ set that can be downloaded. There are several ice cores, each with the own time resolution, from different places, with different local climate, etc. I’ll quote from a recent paper by Webber and Higbie http://arxiv.org/ftp/arxiv/papers/1004/1004.2675.pdf [but also published in JGR]
“When the first detailed 10Be measurements from polar ice cores were reported (e.g., Beer, et al., 1990) there was the hope that this ice core data could provide a “monitor” of past solar activity as it effects cosmic ray intensities incident on the Earth, in much the same way as neutron monitors are used to monitor this solar activity in the modern era (Beer, 2000). This “concept” with its 1:1 correspondence between 10Be production and 10Be in ice cores, has since been used extensively to interpret historical 10Be ice core data in terms of changes in heliospheric conditions and their effect on cosmic ray intensities incident on the Earth. Our results show that, given our current understanding (or lack of it) of the correspondence between 10Be production, sunspot numbers and the 10Be observed in ice cores, this is really not a reliable “concept” to use for historical extrapolation. The sunspot number itself remains the best indicator of cyclic (11 year) solar activity after ~1700 A.D. The level of 10Be production in the Earth’s atmosphere at the minimum of the 5 most recent solar activity cycles is the same to within 5%. If this production level has changed in the past, then the present uncertainties in the 10Be ice core data are such that the magnitude of these changes cannot be robustly determined. Calculations also show that if the LIS remains the same as it is now, the 10Be production should never increase by a factor of more than 1.3-1.5 over the average modern values at sunspot minimum at any time in the recent past, whereas increases by a factor ~2.0 have been observed in the 10Be ice core data. In order that ice core data may in the future be utilized to provide an accurate historical record of cosmic ray intensity incident on the Earth’s polar atmosphere, new measurements or analyses need to be made. The measurements would need to include comprehensive yearly measurements of 10Be covering the last 60 years (several 11 year cycles) up to and including 2009, in several nearby (within a few km) ice cores in order to isolate and understand the origin of the large fluctuations observed in the individual yearly ice core data.”

kim says:
June 29, 2010 at 11:21 am
Isotope record supports a non-climatic response to the Maunder Minimum?
One swallow does not make a summer. You can’t deduce much from a singular occurrence.
A grand, simple, and unanswered question is whether Solar Grand Minima cool the earth. I believe you doubt it, but how much do you doubt it?
Since their is no good evidence for this, I doubt it very much [89.53%]. My arguments are summarized here: http://www.leif.org/research/Does%20The%20Sun%20Vary%20Enough.pdf page 20 tells the story in a single Figure. ‘TSI’ is just used here as a generic term for solar activity [in Fact, the TSI on the figure was derived from cosmic ray modulation].

oneuniverse says:
June 29, 2010 at 2:11 pm
this conclusion does not exclude that, for instance, the cosmic ray intensity may have been twice higher than at present during 10^5 years in the period 10^6 years before present.
but it also does not support that idea. But see my remarks just posted.

oneuniverse says:
June 29, 2010 at 4:51 pm
There is no evidence that I’m aware of, since we’re not considering 10Be and I assume 14C proxies.
Perhaps I misunderstood your statement. I took it to mean ‘we [you and I] are not considering 10Be and I [i.e. you alone] assume we are considering 14C proxie[s]’.
But perhaps you were not considering proxies at all, which means that we have no knowledge [indirect or direct] of GCR flux before 1953, so the whole thing is moot.

Leif:
So the center of the Sun may actually be hollow.
Now you are way out there with some of the other esteemed pseudo-scientists that frequent this blog. For all this is a sad state of affairs.
Sorry Leif, I must protest. I am not a scientist (pseudo or otherwise), I am an intelligent layman with a difficulty understanding a particular point of solar-cosmic science. And I have to say, you are not helping me understand anything here.
a. We have now agreed that matter is weightless at the center of the Sun (not anywhere within the Sun, as that website you linked said).
b. With the many eddies and currents in the Sun’s matter, it is not beyond the realms of possibility that a small vortex or void may be created within this weightless material, right at the center of the Sun (by small, say 100km or so across).
c. Any matter on the edge of this void will experience a stronger gravity gradient on its side of this void (the matter there is closer). The difference would be small, but measurable.
d. Such an asymmetric force would tend to perpetuate the void, so it becomes a stable feature.
e. Nothing you have said prevents me from thinking that this is a perfectly reasonable thought experiment. In fact, you have made no reasonable comment at all.
.

>>> d. Such an asymmetric force would tend to perpetuate the
>>> void, so it becomes a stable feature.
And as evidence m’lud, I present before the jury the recent case of the Coriolis Force (or effect). The said force is a mere trifle in climatic terms, barely enough to perturb the wings of a butterfly, and yet its constant presence creates and sustains a hurricane. I rest my case.
http://en.wikipedia.org/wiki/Coriolis_effect
.