Guest post by Alec Rawls
In an interview with NewScientist magazine, Imperial College professor of atmospheric physics Joanna Haigh scoffs at the idea that late 20th century warming could have been caused by the sun:
Haigh points out that the sun actually began dimming slightly in the mid-1980s, if we take an average over its 11-year cycle, so fewer GCRs should have been deflected from Earth and more Earth-cooling clouds should have formed. “If there were some way cosmic rays could be causing global climate change, it should have started getting colder after 1985.”
What she means is that the 20th century’s persistent high level of solar activity peaked in 1985. That is the estimate developed by Mike Lockwood and Claus Fröhlich. The actual peak was later (solar cycle 22, which ended in 1996, was stronger than cycle 21 by almost every measure) but set that aside. Who could possibly think that cooling should commence when forcings are at their peak, just because the very highest peak has been passed?
Haigh’s argument against solar warming was in response to my suggestion that one new sentence in the leaked Second Order Draft of AR5 is a “game changer.” That is the sentence where the authors admit strong evidence that some substantial mechanism of solar amplification must be at work. The only solar forcing in the IPCC’s computer models is Total Solar Irradiance so if some solar forcing beyond TSI is also at work then all their model results are wrong.
No, no, no, Haigh told the NewScientist, it is “the bloggers” who have it all wrong:
They’re misunderstanding, either deliberately or otherwise, what that sentence is meant to say.
Look whose accusing people of misunderstanding. This woman thinks that warming is driven, not by the level of the temperature forcing, but by the rate of change in the level of the forcing. When a forcing goes barely past its peak (solar cycle 22 nearly identical in magnitude to cycle 21), does that really create cooling? Haigh should try it at home: put a pot of water on a full burner for a minute then turn the burner down to medium high. Does she really think the pot will stop warming, or that it will actually start to cool?
“Deliberately or otherwise,” this is an astounding misunderstanding of the very most basic physics, and Haigh is not the only consensus scientist who is making this particular “mistake.” Hers is the stock answer that pretty much every “consensus” scientists gives when asked about the solar-warming hypothesis. I have collected examples from a dozen highly regarded scientists: Lockwood, Solanki, Forster, Muscheler, Benestad, and more. Not surprisingly, it turns out that they are all making some crucial unstated assumptions.
Solar warming and ocean equilibrium
To claim that the 20th century’s high level of solar forcing would only cause warming until some particular date such as 1970, or 1980, or 1987, one must be assuming that the oceans had equilibrated by that date to the ongoing high level of forcing. That’s just the definition of equilibrium. After a step up in forcing the system will continue to warm until equilibrium is reached.
When I asked these scientists if they were making an unstated assumption that the oceans must have equilibrated by 1980 say to whatever forcing effect high 20th century solar activity was having, almost all of them answered yes, each giving their own off-the-cuff rationale for this assumption, none of which stand up to the least bit of scrutiny. Isaac Held’s two-box model of ocean equilibration is better than Mike Lockwood’s one-box model, but just move to the next simplest model, a three-box model of ocean equilibration, and any idea that longer term forcing won’t cause longer term warming collapses.
The well mixed upper ocean layer (the top 100-200 meters) does equilibrate rapidly to a change in forcing, showing a response time of less than ten years, but that isn’t the end of the story. As the top layer warms up it transfers heat to the next deeper ocean layers. If the elevated forcing persists then these next deeper layers will continue to warm on the time scale of multiple decades to multiple centuries. This warming will reduce the temperature differential between the upper and deeper layers, causing there to be less and less heat loss over time from the upper to the deeper layers, causing the upper layer to continue to warm on the time scale of multiple decades to multiple centuries.
This accords with what we actually see. Since the 50 year absence of sunspots that coincided with the bottom of the Little Ice Age, 300 years of uneven warming have coincided with an uneven rise in solar activity. Any claim that these three centuries of natural warming had to have ended by a particular 20th century date (never mind right when solar activity was at its peak), is at the very least highly speculative. To claim that we can be confident that this is what happened is borderline insane.
Or maybe it’s that other thing that Joanna Haigh insinuates about. Maybe there is an element of deliberateness to this “misunderstanding” where scads of PhD scientists all pretend that warming is driven by the rate of change of the temperature forcing, not the level of the forcing. How else to blame late 20th century warming on human activity? Some rationale has to be given for why it can’t have been caused by the high level of solar activity that was still raging. Aha, what if temperature were driven by the trend in the forcing rather than the level of the forcing? That would do it. Let’s say that one. Let’s pretend that even peak forcing will cause cooling as soon as the trend in the forcing turns down.
It’s one psycho-drama or the other: either Haigh’s insinuations about dishonesty are projection, accusing others of what she and her cohorts are actually doing, or she’s just dumber than a box of rocks.
Haigh also channels Steven Sherwood, pretending that the highlighted sentence is just about GCR-cloud
The draft report acknowledges substantial evidence for some mechanism of solar amplification and lists Henrick Svensmark’s GCR-cloud theory as an example of one possible such mechanism (7-43 of the SOD):
Many empirical relationships have been reported between GCR or cosmogenic isotope archives and some aspects of the climate system (e.g., Bond et al., 2001; Dengel et al., 2009; Ram and Stolz, 1999). The forcing from changes in total solar irradiance alone does not seem to account for these observations, implying the existence of an amplifying mechanism such as the hypothesized GCR-cloud link.
Haigh claims that the evidence about cloud formation being induced by cosmic rays points to a weak mechanism, then simply ignores the report’s admission of substantial evidence that some such mechanism must be at work:
Haigh says that if Rawls had read a bit further, he would have realised that the report goes on to largely dismiss the evidence that cosmic rays have a significant effect. “They conclude there’s very little evidence that it has any effect,” she says.
Rawls says that if Haigh had read the actual sentence itself, she would have realized that it isn’t about galactic cosmic rays, but only mentions GCR-cloud as one possible solar amplifier.
Aussie climatologist Steven Sherwood did the same thing, claiming (very prematurely) that the evidence does not support GCR-cloud as a substantial mechanism of solar amplification, then pretending away the report’s admission of clear evidence that some substantial such mechanism is at work:
He says the idea that the chapter he authored confirms a greater role for solar and other cosmic rays in global warming is “ridiculous”.
“I’m sure you could go and read those paragraphs yourself and the summary of it and see that we conclude exactly the opposite – that this cosmic ray effect that the paragraph is discussing appears to be negligible,” he told PM.
As JoNova and I blogged last weekend, this ploy inverts the scientific method, using theory (dissatisfaction with one particular theory of solar amplification) as an excuse for ignoring the evidence for some mechanism of solar amplification. Using theory to dismiss evidence is pure, definitional anti-science. Unfortunately, NewScientist gives this slick anti-scientist the last word:
“The most interesting aspect of this little event is it reveals how deeply in denial the climate deniers are,” says Steven Sherwood of the University of New South Wales in Sydney, Australia – one of the lead authors of the chapter in question. “If they can look at a short section of a report and walk away believing it says the opposite of what it actually says, and if this spin can be uncritically echoed by very influential blogs, imagine how wildly they are misinterpreting the scientific evidence.”
Sherwood and Haigh are flat lying to the public about what a simple single sentence says, pretending the admission of strong evidence for some substantial mechanism of enhanced solar forcing was never made, then trusting sympathetic reporters and editors not to call them on it. This is why the report had to be made public. After my submitted comments showed how thoroughly the new sentence undercuts the entire report it was obvious that the consensoids who run the IPCC would take the sentence right back out, and here Sherwood and Haigh are already trying to do exactly that.
Too late, anti-scientists. Your humbug is on display for the whole world to see.
lsvalgaard says: December 22, 2012 at 9:22 am
………
Dr. S
Are you saying that the palaeomagnetism is rubbish, and reversals of the Earth’s magnetic field are ‘spurious’ clams, since according to you nothing is known about the Earth’s magnetic field variability before 1832 ?
Leif:”I would rather put it this way: since the solar changes are so small, supporters of the notion that the Sun is the major driver need to invoke unspecified or unknown ‘amplification’ mechanisms. This does not mean that any such mechanisms actually are operating as it has not been established that the Sun is a major driver.
On Bond: as he correctly relalizes that TSI won’t do it, he needs an ‘additional’ mechanism. This is not an ‘amplification’ of the TSI influence.”
I agree that we don’t know the mechanism but it is well nigh impossible to explain the sorts of relationships Bond and others find without assuming that something else is going on. It is prefectly reasonable even in the absence of understanding of that mechanism to believe in that amplification. It is *possible* that this is mistaken but nothing has been brought up that shows that it is. All science is tentative, obviously.
In re: what Bond is actually saying, I don’t understand your point at all (it seems so obviously false). Here is the man in his own words.
From his paper:”The surface hydrographic changes may have affected production of North Atlantic Deep Water, potentially providing an additional mechanism for amplifying the
solar signals and transmitting them globally”
Cheers, 🙂
Carter, the scientist in your video refuses to show her evidence. Never has she archived, so nothing was said, scientifically. It’s just her say-so.
You’re a believer, not a thinker.
thisisnotgoodtogo says:
December 22, 2012 at 10:29 am
You’re a believer, not a thinker.
Now, this is good to go: 95% of the commenters here are believers, too.
Carter says:
December 22, 2012 at 9:11 am
‘Wrong, as usual’ so who doI believe? A nobody on the interweb or respected scientists or journalists? Now lets think about that, because it’s a difficult one!
AGU ice core data, that debunks a global MWP and confirms the ‘Hockey Stick’…..
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
I believe the peer-reviewed science and not some guy with an obvious blind spot.
You can use either of these to find that peer-reviewed information.
Was there a Medieval Warm Period? YES, according to data published by 1091 individual scientists from 625 research institutions in 46 different countries …
Understanding the Medieval Warm Period Project Interactive Map and Time Domain Plot
This includes a compilation of papers from ALL continents not just the Northern Hemisphere.
Here are two NEW major proxy studies were released in April and June 2012 to get you started on your reading assignment.
Get back to us after you have read ALL the papers.
Carter,
As I helpfully explained to you: Unlike your incredible New Scientist fantasy source, the charts I provided here were constructed from verifiable peer reviewed data. They show conclusively that the LIA was a global event, and it was much colder than average Holocene temperatures.
You put yourself in the untenable position of arguing with ice core data and other proxies, and with extensive peer reviewed data, and with the vast preponderance of scientists who know that the LIA and the MWP were global events. There is no doubt about the LIA, but it rocks your belief system, so you impotently argue about it.
You refuse to accept any data that contradicts your wild-eyed belief system. That places you squarely in the climate True Believer cult. Science has nothing to do with your belief, and your belief has nothing to do with science.
It is a fact that global warming has stalled. It may resume. Or not. But your belief that “carbon” is at fault for global warming is contradicted by Planet Earth.
So, what should we believe? What Carter is saying? Or what Planet Earth is saying? Becuase they are mutually contradictory. For myself, I do not accept the pseudo-scientific ranting of lunatics. I accept what the ultimate Authority, the planet, is telling us. But Carter refuses to listen to Planet Earth.
Run along now, Carter, and go watch your propaganda videos, since you are not capable of debating or refuting the facts — like the ones Gail Combs just provided for your edification. You could learn plenty from them. But you won’t. The cognitive dissonance between reality and your fantasy might make your head explode. We wouldn’t want that, would we?
vukcevic says:
December 22, 2012 at 10:17 am
Are you saying that the palaeomagnetism is rubbish, and reversals of the Earth’s magnetic field are ‘spurious’ clams, since according to you nothing is known about the Earth’s magnetic field variability before 1832 ?
Paleomagnetic measurements of the intensity and polarity going back thousands or millions of years are largely correct [with large errorbars, of course]. What is rubbish is the belief that that data is correct, or can be even estimated, on an annual basis and in areas where there is no data [such as the Arctic and Antarctic]. The spherical harmonic coefficients can be calculated from actual data and from those we can approximate the field at those data points, but not with any accuracy in areas where there is no data [we cannot make up data where there is none].
Shawnhet says:
December 22, 2012 at 10:22 am
I agree that we don’t know the mechanism but it is well nigh impossible to explain the sorts of relationships Bond and others find without assuming that something else is going on. It is perfectly reasonable even in the absence of understanding of that mechanism to believe in that amplification. It is *possible* that this is mistaken but nothing has been brought up that shows that it is. All science is tentative, obviously.
The ‘Bond events’ with a near 1500 yr period are not found in modern reconstructions of solar activity, e.g. http://www.leif.org/research/TSI-10000-yrs.png from http://www.leif.org/EOS/PNAS-2012-Steinhilber-Appendix.pdf so the ‘evidence’ is weak.
From his paper:”The surface hydrographic changes may have affected production of North Atlantic Deep Water, potentially providing an additional mechanism for amplifying the solar signals and transmitting them globally”
As I said, I have discussed these thing personally with the late Gerard Bond and what he is hinting at is that TSI must have some effect [with which I agree], but since that effect is too small to explain large climatic changes, he thinks there must be ‘an additional [and different]’ mechanism at work. This is not to thought of as an ‘amplification’ of the small TSI effect, but as a way of getting more out of the small solar changes [perhaps of a different nature: UV, GCRs, whatever]. What that additional mechanism might be, he does not speculate on [just says ‘solar-triggered’]. A hypothesis that is en vogue is the GCR-cloud one and that is why IPCC chooses to look at that one, rather than speculate about unknown and unspecified ‘solar triggers’. This is perfectly reasonable to me, and does not mean that IPCC endorses the unknown and unspecified triggers.
Gail Combs says: December 22, 2012 at 10:43 am
Get back to us after you have read ALL the papers.
========================
carter does not read. He watches videos. It’s easier, you see.
lgl says:
December 22, 2012 at 3:21 am
When does the Steinhilber TSI show the steepest fall last 2000 years? Exactly, around 1250.
Gail Combs says:
December 22, 2012 at 10:43 am
The two-millennia long reconstruction shows a well defined Medieval Warm Period with a peak warming ca. AD 950–1050
So, the Earth’s climate knows how to predict solar changes 200 years ahead of time. Perhaps you should do some more integrations.
The claim that 1985 is the peak was only based on Sun Spot Numbers and even this isn’t correct with the peak declining after 1987 using 121 month mean. TSI shows the peak recently between 1977 and 1995 with global temperatures not warming much longer than this period. Only 3 years later with the big 1997/98 El Nino did global temperatures continue to rise, especially when taking the change in low global cloud albedo into account.
http://img823.imageshack.us/img823/6873/had3vlowcloudvsolar2.png
When taking changes in global low cloud into account these explain the warming of the planet since the 1980’s. Declining low level cloud warms the surface because the energy from the sun increases it’s surface area. Therefore it is the sun that’s done it indirectly, but what caused the decline in low level clouds?
Can’t be CO2 because it it would produce more water vapor and increase low cloud levels. Could be the sun’s affect on the atmosphere by changing the position of the jet stream across the hemisphere’s, particularly since 2007. This theory can quickly change the atmosphere without changing the ocean heat content at first, so we see changes in weather patterns, but little change in the ocean heat content at least at first. With decreased low cloud albedo compared with previous decades, explains why global temperatures are still in the warmish levels before the energy from the oceans get chance to release. An increase in low cloud global levels only need to change by about 3 or 4 percent to bring us back to 1970’s levels.
Leif:”The ‘Bond events’ with a near 1500 yr period are not found in modern reconstructions of solar activity,”
I’m sorry but this is a little opaque to me. Are you saying that TSI doesn’t change as much as Bond assumed at the time of his paper or that the actual measurements he was using (ie for carbon-14 or whatever) are wrong? If the former, I can’t see how that impacts the idea that an amplification is suggested at all(except to suggest that the amplification may need to be higher).
” This is not to thought of as an ‘amplification’ of the small TSI effect, but as a way of getting more out of the small solar changes [perhaps of a different nature: UV, GCRs, whatever]. ”
??? Uh, getting more out of the small solar changes is just another way of saying that the small solar changes are amplified somehow.
Forgot to mention, notice this;-
“TSI shows the peak recently between 1977 and 1995”
Global temperatures started to warm after 1980, 3 years later and they stopped warming 3 years after 1995.
What’s wrong mods am I too near the truth for you?
REPLY: It got caught be the SPAM filter due to word combinations, and still in moderation, and mods brought it to my attention. Tell you what, if you want to denigrate rather than debate, put your full name to your claims, as I do, and then your comment would be on par with what I do every day, putting my name to this entire website. Ball’s in your court.
– Anthony
Shawnhet says:
December 22, 2012 at 11:23 am
Are you saying that TSI doesn’t change as much as Bond assumed at the time of his paper
The dips or minima do not recur at the 1500-yr period he suggests.
??? Uh, getting more out of the small solar changes is just another way of saying that the small solar changes are amplified somehow.
Here is one interpretation: TSI has some small effect. A much larger effect is due to GCR-clouds [say]. The latter is not an amplification of the former [different mechanisms].
Shawnhet says:
December 22, 2012 at 11:23 am
Are you saying that TSI doesn’t change as much as Bond assumed at the time of his paper
The dips or minima do not recur at the 1500-yr period he suggests.
I’m saying that the situation is complex and not so clear cut as Bond assumed. I don’t have the full thesis manuscript, but this abstract illustrates some of the problems:
Glacial North Atlantic millennial variability over the last 300,000 years
Obrochta, Stephen Phillip
Thesis (Ph.D.)–Duke University, 2008.; Publication Number: AAI3336170;
The hematite-stained grain (HSG) proxy method, commonly employed by the late G.C. Bond to detect the “1500-year cycle” in North Atlantic climate, is reproduced and verified for the first time. The exact method is compiled from various sources and presented in Chapter 1. In Chapter 2, an HSG record from classic North Atlantic DSDP Site 609 is reconsidered. While the Site 609 HSG record was initially interpreted to exhibit 1500-year variability, it did not actually contain spectral power at the 1500-year band. The chronology for Site 609 is based on radicarbon dates to 26 ka, beyond which the sea surface temperature record is matched to the record of air temperature variations over Greenland from the GISP2 ice core. However, it is now evident that the lack of spectral power at the primary period of the observed fluctuation was likely due to the GISP2 chronology, which has been subsequently shown to become progressively deficient over the course of the last glaciation. Updating the Site 609 chronology to the latest chronology for the virtually complete NGRIP Greenland ice core, which is based on layer counting to 60 ka, results in 99% significant spectral power at a 1/1415 year frequency. In Chapter 3, the classic Site 609 lithic records are extended to the previous two glaciations, glacial Stages 6 and 8, at IODP Site U1308 (reoccupied Site 609). The “1500-year cycle” is not detected within Stage 6, perhaps indicating that D-O Events were not manifest in a similar fashion, if at all. Heinrich Event are also not detected, indicating relative stability of the North American Laurentide Ice Sheet during Stage 6. As a result, individual North Atlantic sites recorded loweriv amplitude, asynchronous hydrographic changes. The SST proxy record at Site U1308 during Stage 6 primarily records intermediate temperatures. The subtle SST changes detected likely indicate local as opposed to basin-scale changes related to the migration of oceanic frontal boundaries. During Stage 6, benthic delta13 C changes are of lower amplitude than Stages 2–4 and correspond more strongly to variations in SST than to ice rafting, indicating that ice-rafting events did not as strongly influence NADW formation. During Stage 8, however, well-structured cycles in HSG with a mean event spacing of ˜1500 +/- 500 years are detected, potentially indicating a greater likelihood of D-O Events during Stage 8. In addition, three Heinrich Events, defined by a large abundance of DC, occurred during MIS 8, indicating surging of the Laurentide Ice Sheet Ice Sheet. Stage 8 is therefore more analogous to that of the last glaciation than Stage 6. Chapter 4 explores the link between HSG and cosmogenic nuclide production, which are highly coherent at a frequency of 1/950 years. A 950-year period is present in the HSG records of the last three glaciations. While a 950-year oscillation may be the product of solar forcing, due to uncertainty in paleomagnetic reconstructions and in the Site U1308 chronology, the null hypothesis that the HSG proxy does not reflect variable solar irradiance cannot be unequivocally refuted. Solar forcing does however provide an explanation for climate variability in the 950-year band during the last three glaciations.
—–
Note the lip-service paid to possible solar forcing in the last sentence [good for funding of further research]
From his paper:”The surface hydrographic changes may have affected production of North Atlantic Deep Water, potentially providing an additional mechanism for amplifying the solar signals and transmitting them globally”
Natural variability of the North Atlantic can be directly associated with Sun – Earth interactions via number of intermediary steps.
http://www.vukcevic.talktalk.net/NaturalVariability.htm
FAO A Watts
‘put your full name to your claims, as I do’, big deal! ‘and then your comment would be on par with what I do every day’ I doubt that!
REPLY: Your denigration comment claims by insinuation that because of who I am I have no right to an opinion. Therefore my counter is that as an anonymous coward, neither do you, but give you a chance to elevate yourself. You have chosen snark over personal integrity, choosing to shoot denigration from behind the veil of anonymity instead. It says much about you. What sort of background do you have that qualifies you to have an opinion (but I don’t )?
You might want to read my about page – Anthony
Arno Arrak says:
December 21, 2012 at 3:41 pm
This non scientist thanks you for your clear and consise comment. And of course Bob Tisdale for his many detailed graphs and explanations on same subject.
This is my probably stupid question for the great minds out there in blogville. If the late last century El Niño caused the so called “unprecedented” CO2 driven warming that the warmistas keep banging on about what is the link between anthropogenic CO2 and that 1998 El Niño?
LOL perhaps the warmistas will convince me that the 1998 El Niño didn’t cause the step up warming.
lsvalgaard says:
December 22, 2012 at 11:31 am
Here is one interpretation: TSI has some small effect. A much larger effect is due to GCR-clouds [say]. The latter is not an amplification of the former [different mechanisms].
BTW, Bond did not believe in the GCR-cloud mechanism, mainly because of the lack of climate response to the Laschamp geomagnetic event about 40,000 years ago.
vukcevic says:
December 22, 2012 at 12:12 pm
Natural variability of the North Atlantic can be directly associated with Sun – Earth interactions
At the South Pole, you claim…
Leif:”Here is one interpretation: TSI has some small effect. A much larger effect is due to GCR-clouds [say]. The latter is not an amplification of the former [different mechanisms].”
Well, not to beat a dead horse here, no one is claiming that the TSI itself is increased by some unknown mechanism. Rather the point is that some unknown mechanism might act in tandem with TSI to make the overall effect on the *climate* bigger.
In re: the paper you link above, I thought you might be interested in the most recent work done by its author which still seems consistent with the solar amplification model. (I don’t have access to the paper)
A re-examination of evidence for the North Atlantic “1500-year cycle” at Site 609
Stephen P. Obrochtaa, , , Hiroko Miyaharab, Yusuke Yokoyamac, Thomas J. Crowley
Ice-rafting evidence for a “1500-year cycle” sparked considerable debate on millennial-scale climate change and the role of solar variability. Here, we reinterpret the last 70,000 years of the subpolar North Atlantic record, focusing on classic DSDP Site 609, in the context of newly available raw data, the latest radiocarbon calibration (Marine09) and ice core chronology (GICC05), and a wider range of statistical methodologies. A ∼1500-year oscillation is primarily limited to the short glacial Stage 4, the age of which is derived solely from an ice flow model (ss09sea), subject to uncertainty, and offset most from the original chronology. Results from the most well-dated, younger interval suggest that the original 1500 ± 500 year cycle may actually be an admixture of the ∼1000 and ∼2000 cycles that are observed within the Holocene at multiple locations. In Holocene sections these variations are coherent with 14C and 10Be estimates of solar variability. Our new results suggest that the “1500-year cycle” may be a transient phenomenon whose origin could be due, for example, to ice sheet boundary conditions for the interval in which it is observed. We therefore question whether it is necessary to invoke such exotic explanations as heterodyne frequencies or combination tones to explain a phenomenon of such fleeting occurrence that is potentially an artifact of arithmetic averaging.
Note the section which states the variations are coherent with the estimates of solar variability.
Cheers, 🙂
@ur momisugly Gail Combs re: “Producing ‘Scientific Reports’ to use to sway uneducated politicians is now ‘big business’ and just as dirty as the rest of politics.”
Thanks Gail and skeptics. You all are fighting the good fight. Frankly, I’m both angry and saddened that science has been hijacked by activists with anti-people agendas.
For those Looking for a good cause other than the insane CO2 fight, I suggest: access to clean water, industrial pollution, malaria, childhood immunization, habitat destruction, human trafficking, many more….
Shawnhet says:
December 22, 2012 at 1:07 pm
Well, not to beat a dead horse here, no one is claiming that the TSI itself is increased by some unknown mechanism. Rather the point is that some unknown mechanism might act in tandem with TSI to make the overall effect on the *climate* bigger.
It was not about TSI itself being increased but the effect of TSI. ‘In tandem’ means then in addition to, not an ‘amplification’ of the original TSI effect.
A re-examination of evidence for the North Atlantic “1500-year cycle” at Site 609
Stephen P. Obrochta, , , Hiroko Miyahara, Yusuke Yokoyama, Thomas J. Crowley
Thanks for the reference. BTW, Hiroko is a good friend of mine, I’ll ask her for the paper.
Note the section which states the variations are coherent with the estimates of solar variability.
In ‘sections’, but not overall. You can always find ‘sections’ where wiggles agree with any two time series. The image remains of a much less clear correlation than in Bond et al. 2001 [perhaps IPCC should not even reference Bond 2001].
[snip – quoting potholer54 is not only off-topic, but irrelevant. Good try at ducking the issue though – Anthony]
Shawnhet says:
December 22, 2012 at 1:07 pm
Well, not to beat a dead horse here, no one is claiming that the TSI itself is increased by some unknown mechanism. Rather the point is that some unknown mechanism might act in tandem with TSI to make the overall effect on the *climate* bigger.
It is comforting that IPCC does not consider ‘some unknown mechanism’ to be worthy of mention.