Guest post by Alec Rawls
Miller et al. 2012 recently provided some pretty strong evidence for a solar driver of climate. “This is the first time anyone has clearly identified the specific onset of the cold times marking the start of the Little Ice Age,” said lead author Gifford Miller in January. And the dates?
LIA summer cold and ice growth began abruptly between 1275 and 1300 AD, followed by a substantial intensification 1430-1455 AD.
As you can see in the graphic above (from Usoskin 2003) these dates correspond pretty much with the midpoints of the Wolf and Spörer solar minima. (Usoskin 2007 centers Wolf at 1305 with a duration of 70 years and Spörer at 1470 with a duration of 160 years.)
Yet Miller never noted this coincidence. In fact, he tried to hide it, claiming that the onset of snow and ice growth coincided with periods of especially high volcanism (debunked both by Willis and by Wired), while dismissing the solar explanation with a misleading reference to the Maunder Minimum:
Our precisely dated records demonstrate that the expansion of ice caps after Medieval times was initiated by an abrupt and persistent snowline depression late in the 13th Century, and amplified in the mid 15th Century, coincident with episodes of repeated explosive volcanism centuries before the widely cited Maunder sunspot minimum (1645–1715 AD [Eddy, 1976]).
This is a remarkably blatant deception, acceded to by 13 co-authors plus the reviewers and editors at Geophysical Research Letters. It takes no expertise to know about the Wolf and Spörer minima. There is no physics involved, so who do these people think they are fooling?
Nobody. They just don’t think it is their job to make the case for what they regard as “the other side.” The anti-CO2 alarmists are behaving like lawyers in an adversarial legal proceeding, hiding what hurts their own case while overstating what can be fashioned in support. In the courts an adversarial system is able to elicit a measure of truth only because there is a judge to maintain rules of evidence and a hopefully unbiased jury examining the facts. These conditions do not obtain in science. The anti-CO2 alarmists are both the peer-review jury and the judge/editors, devolving into a pre-scientific ethic where acceptance is determined by power, not reason and evidence.
The lawyerly behavior of Miller et al. lead them to embrace a particular excuse for ignoring the evidence for a powerful solar driver of climate (even evidence that they themselves uncover). They don’t “need” it. But they were not the pioneers of this anti-scientific ploy. That dishonor goes to Gavin Schmidt.
Miller’s two null hypotheses, specific and general
The specific hypothesis of Miller’s paper is a feedback mechanism by which the cooling from volcanic episodes could get amplified into longer term cooling. It is “tested” via climate model. From Miller’s University of Colorado press release:
The models showed sustained cooling from volcanoes would have sent some of the expanding Arctic sea ice down along the eastern coast of Greenland until it eventually melted in the North Atlantic. Since sea ice contains almost no salt, when it melted the surface water became less dense, preventing it from mixing with deeper North Atlantic water. This weakened heat transport back to the Arctic and creating a self-sustaining feedback system on the sea ice long after the effects of the volcanic aerosols subsided.
But the real null hypothesis of the paper, the one that expresses the authors’ motivation, as revealed by blatant cover-up of their own evidence for a solar driver of climate, is more general. It appears in the last line of their abstract, which says that in order to explain the Little Ice Age, “large changes in solar irradiance are not required.”
The timings Miller found point like a neon sign to a solar explanation but he is determinedly oblivious to that evidence. He is only interested in whether there could be some other possible explanation, and as long as that null hypothesis is not absolutely falsified, he takes that as a rationale for ignoring the alternative hypothesis and the evidence for it.
What exactly is the alternative hypothesis? According to Miller’s wording, it is that the Little Ice Age was actually caused by “large changes in solar irradiance.” But nobody thinks that there have been large changes in solar irradiance. There is broad agreement that while solar magnetic activity fluctuates dramatically, solar irradiance remains almost constant. Irradiance shifts towards the UV when solar activity is high, but the change in Total Solar Irradiance is too small to bring about much decadal or century scale variation in climate.
In contrast, there is a great deal of evidence for a solar-magnetic driver of climate (second section here). This is the real alternate hypothesis, and there is at least one well developed theory for how it could occur: Henrik Svensmark’s GCR-cloud.
As a good adversarial lawyer, Miller is unwilling to betray any hint that this alternate hypothesis is even a possibility. Like Voldemart, it is the foe that “must not be named.” Thus Miller refers to the possible solar-magnetic driver of climate indirectly and incorrectly as “large changes in solar irradiance.”
Lawyerly advocacy is not science
In his role as an advocate, Miller’s fear is fully justified. A strong solar-magnetic effect on climate would be a death knell for anti-CO2 alarmism. Any late 20th century warming that can be attributed to that era’s continued high levels of solar activity reduces by the same amount the warming that can possibly be attributed to CO2, which in tern reduces the implied sensitivity of climate to CO2. Even worse, if solar-magnetic effects actually outweigh CO2 effects (my own surmise, by a wide margin) then the present danger is cooling, not warming, thanks to our now quiescent sun.
But lawyerly advocacy is not science. To only examine the evidence for non-solar explanations is to throw away information, violating the most basic scientific rationality, yet this is what the “consensus” has been doing for many years. My review of the first draft of the next IPCC report documents how “vast evidence for solar climate driver rates one oblique sentence in AR5.” AR4 listed Total Solar Irradiance (TSI) as the only solar effect on climate, as did the Third Assessment Report (scroll to TSI). “The Team” simply omits what they wish to avoid.
Miller plays this game from the get go, where his opening literature review assumes that the only solar effect is TSI:
Episodes of anomalously cold summers primarily are attributed to some combination of reductions in solar irradiance, especially the LIA Maunder sunspot minimum [Eddy, 1976], explosive volcanism, and changes in the internal modes of variability in the ocean–atmosphere system [Crowley, 2000; Wanner et al., 2011]. However, the natural radiative forcings are either weak or, in the case of explosive volcanism, shortlived [Robock, 2000], thus requiring substantial internal feedback.
Robock 2000 only addresses the volcanic issue, so Miller’s only grounds for calling solar forcing a “weak” effect is his own analysis, where he only looks at TSI (using the TSI reconstruction of Schmidt et al. 2011).
That’s a phony literature review. Miller’s repeated deceptions—hiding the Wolf and Spörer minima, referring to large solar effects as “large changes in solar irradiance” when there is no such hypothesis—can only be to hide the possible role of solar magnetic activity, but this actual object of Miller’s paper goes unmentioned in what is supposed to be a survey of the most relevant science. The literature review is a place where an adversarial approach is explicitly rejected by well established scientific standards, but the alarmists are not playing by the rules.
There is nothing wrong with Miller et al. testing their hypothesis that solar activity does not play a significant role (which they do by “setting solar radiation at a constant level in the climate models”). But when they pair this non-falsification of their pet theory with blatant misdirection about their own discovered evidence for the alternative hypothesis, that is bad. It is using the “not needed” claim as an implicit justification for the omitted variable fraud that the entire consensus is engaged in.
Gavin Schmidt is a pioneer of the “not needed” excuse for ignoring possible solar magnetic effects
Some history on this particular ploy, for anyone who is interested. Miller and his co-authors are not the first to pull the “not needed” gambit. Eleven years ago Shindell, Schmidt, Mann, Rind and Waple published a paper in Science that is remarkably similar to Miller 2012. Like Miller, Schmidt and his co-authors propose a North Atlantic mechanism for amplifying cooling effects, though the mechanism itself is quite different. The spectral shift that accompanies decreased solar activity is hypothesized to alter atmospheric ozone composition in a cooling direction, setting in motion atmospheric flows (“planet waves”) that in turn are hypothesized to drive the North Atlantic Oscillation. Their null hypothesis is the same as Miller’s: that they can account for the Little Ice Age without invoking any solar effects beyond the expected variations in solar irradiance, and their test is also the same: they run a model.
If the UV shift that goes with low solar activity can explain much of the Little Ice Age, couldn’t the UV shift from high solar activity explain a similar amount of 20th century warming? No say Shindell et al. Changes in atmospheric composition from the pre-industrial to the industrial period supposedly cause the effect of the UV shift to reverse (p. 2151):
Ozone’s reversal from a positive (preindustrial) to a negative feedback supports results showing that solar forcing has been a relatively minor contributor to late 20th-century surface warming (7, 19, 31).
Thus the CO2 explanation for recent warming is not undercut, enabling claims of future catastrophic warming to go forward. Of course Schmidt’s references “showing that solar forcing has been a relatively minor contributor to late 20th-century surface warming” only look at TSI, and his “ozone reversal” is not an empirical finding but a model result. They’ve got all the doors manned.
In 2005, this 2001 paper became the centerpiece of a public exchange between Gavin Schmidt and science fiction author Jerry Pournelle. Schmidt was vigorously insisting on the scientific integrity of himself and everyone he knew:
None, not one, of the climate scientists I meet at conferences or workshops or that I correspond with fit the stereotype you paint of catastrophists making up worries to gain grant money. Personally, I don’t think I’ve ever made a dramatic statement in papers, public speechs, grant applications or letters to the editor. Yet I still manage to keep my job and support a couple of graduate students. This is the same in every institution and university. … I do not go around being a doom sayer – but it is incumbent on scientists to explain to people what it is we think we understand, and what it is we don’t.
To explain the sober science that causes him to dismiss the solar-warming hypothesis, Schmidt invoked his 2001 paper with Shindell et al.. It shows that there is no “need” to bring in any suspicious “new physics” (Schmidt’s Voldmartian euphemism for the solar-magnetic hypothesis that must not be named):
I was a co-author of a paper in Science in 2001, that looked at whether climate models could replicate this pattern given the known physics of solar change. We found that two features were key, allowing the solar irradiance to vary more in the UV than in the visible (consistent with what is seen over the sunspot cycle), and allowing the ozone field to vary as a function of the UV and temperature in the stratosphere. With both of these effects, the model produced global cooling (as you would expect) but also a robust change to the circulation (a weakened NAO) that amplified the cooling in western Eurasia and over the mid-latitude continents. Obviously given the uncertainties in the forcing, the data that we were trying to match, and uncertainty in the model response, we can’t use this a proof that we got all of it right. However, in the absence of better data, there is no obvious need for ‘new’ or unknown physics to explain what was going on. This was just a first cut, and better models and more data are being brought to bear on the problem, so the conclusion may change in the future. As of now though, this is still the current state of thinking.
“New or unknown physics” is obviously a reference to to GCR-cloud, which Schmidt finds lacking as a theory. Fine, but that is no excuse for ignoring the ever growing mountain of evidence that there is some mechanism by which solar activity is having a much larger effect on climate than can be explained by changes in solar irradiance. I compile some of that evidence in the second section here. For the state of that evidence in 2001, the Third Assessment Report’s section 6.11.2.2 on “Cosmic rays and clouds” is well worth a look.
While AR4 and AR5 have progressively excised the evidence for solar activity as a powerful driver of global temperature, TAR actually began with several paragraphs of studies that found substantial correlations between solar activity and climate. Only then did it judge the proposed mechanisms that might account for these correlations to be too uncertain to include in their modeling.
That would be okay if they still took the discovered correlations into account in formulating their climate predictions, but of course they did not. This is the highly improper step that invalidates the IPCC’s entire enterprise. They are using theory (in particular, their dissatisfaction with Svensmark’s GCR-cloud theory) as an excuse to ignore the evidence that supports the theory, excising its known predictive power from their predictive scheme.
Evidence is supposed to trump theory, not vice versa. The IPCC is inverting the scientific method. It is literal, definitional, anti-science, and Schmidt’s “no need” excuse is simply another justification for doing the same thing. Since there is no need to invoke a strong solar driver of climate, he is going to ignore the evidence for a strong solar driver of climate, and this is what Schmidt holds up to Pournelle as an example of his integrity: the very point where he justifies the omitted variable fraud that is being perpetrated by himself and his cohorts. If only he were capable of embarrassment.
Who is actually doing a suspicious new kind of physics?
Schmidt looks askance at GCR-cloud as “new physics,” but it isn’t new in any fundamental sense. The cloud micro-physics that Svensmark, Kirkby and others are looking at is presumed to follow established particle physics models. It is a new application of current physics. What Schmidt is really suggesting with his jaundiced eye is that we should be reluctant to extrapolate our current understanding of physical principles to illuminate the biggest scientific controversy of the day.
At the same time, he and Miller and the rest of the alarmists have introduced something that really is new and problematic. They are using model runs to test their hypotheses. They are using theory to test theory, with no empirical test needed. Here Miller describes how he “tests” his theory about ocean feedbacks (page 3 of 5):
Climate modeling reveals one such possible feedback mechanism. Following Zhong et al. [2011], we tested whether abrupt LIA snowline depressions could be initiated by decadally paced explosive volcanism and maintained by subsequent sea-ice/ocean feedbacks. We completed a 550-year transient experiment (1150–1700 AD) using Community Climate System Model 3 [Collins et al., 2006] with interactive sea ice [Holland et al., 2006] at T42 x 1 resolution. Our transient simulation was branched off a 1000 AD control run, and forced solely by a reconstructed history of stratospheric volcanic aerosols and relatively weak solar irradiance changes (Figure 2b) [Gao et al., 2008].
Models are not reality, and in the above case the model is known to be wrong. Total solar effects are presumed to be “weak”? That is what the alarmists all assume but it is not what the empirical evidence says, and while they may be able to tweak their models enough to keep them from being strictly falsified by the LIA, the last decade of no significant warming has them stumped completely.
General Circulation Models are the most elaborate hypotheses ever concocted. They involve thousands of questionable steps, iterated thousands of times. To illustrate, the Shindell-Schmidt paper is good enough to provide us with a highly abridged description of the hypothetical steps that their model works through. It gives some idea of the volume and sweep of what they are theorizing (p. 2150). (If you are actually going to read this, brace yourself):
Our previous studies have demonstrated how external forcings can excite the AO/ NAO in the GISS GCM (22, 25). Briefly, the mechanism works as follows, using a shift toward the high-index AO/NAO as an example: (i) tropical and subtropical SSTs warm, leading to (ii) a warmer tropical and subtropical upper troposphere via moist convective processes. This results in (iii) an increased latitudinal temperature gradient at around 100 to 200 mbar, because these pressures are in the stratosphere at higher latitudes, and so do not feel the surface warming (26). The temperature gradient leads to (iv) enhanced lower stratospheric westerly winds, which (v) refract upward-propagating tropospheric planetary waves equatorward. This causes (vi) increased angular momentum transport to high latitudes and enhanced tropospheric westerlies, and the associated temperature and pressure changes corresponding to a high AO/NAO index. Observations support a planetary wave modulation of the AO/NAO (27, 28), and zonal wind and planetary wave propagation changes over recent decades are well reproduced in the model (22).
Reduced irradiance during the Maunder Minimum causes a shift toward the lowindex AO/NAO state via this same mechanism. During December to February, the surface in the tropics and subtropics cools by 0.4° to 0.5°C because of reduced incoming radiation and the upper stratospheric ozone increase. Cooling in the tropical and subtropical upper troposphere is even more pronounced (;0.8°C) because of cloud feedbacks, including an ;0.5% decrease in high cloud cover induced by ozone through surface effects. A similar response was seen in simulations with a finer resolution version of the GISS GCM (14). This cooling substantially reduces the latitudinal temperature gradient in the tropopause region, decreasing the zonal wind there at ;40°N. Planetary waves coming up from the surface at mid-latitudes, which are especially abundant during winter, are then deflected toward the equator less than before (equatorward Eliassen-Palm flux is reduced by 0.41 m2/s2, 12° to 35°N, 300 to 100 mbar average), instead propagating up into the stratosphere (increased vertical flux of 6.3 3 1024 m2/s2, 35° to 60°N, 100 to 5 mbar average) (29). This increases the wavedriven stratospheric residual circulation, which warms the polar lower stratosphere (up to 1°C), providing a positive feedback by further weakening the latitudinal temperature gradient. The wave propagation changes imply a reduction in northward angular momentum transport, hence a slowing down of the middle- and high-latitude westerlies and a shift toward the low AO/NAO index. Because the oceans are relatively warm during the winter owing to their large heat capacity, the diminished flow creates a cold-land/ warm-ocean surface pattern (Fig. 1).
That is a LOT of speculation. Normally it is all hidden. They just say, “we did a model run,” but this is what it actually means: ten thousand questionable steps iterated a hundred thousand times. It is fine for people to be working on these models and trying to make progress with them, but to use them to make claims about what is actually happening in the world is insane, and using them as an excuse for ignoring actual empirical evidence is worse than insane.
This really is a new kind of science, and not one that stands up to scrutiny. We are being asked to turn our world upside down on the strength of the most elaborate speculations in the history of mankind, yet Schmidt thinks it is cloud microphysics—traditional science!—that should be eschewed. All to justify the destruction of the modern world, now well underway.
Lars P. says:
April 30, 2012 at 12:45 pm
If there has been a systematic error of 5 W/m2 for “energy in” has there been another systematic error of 5 W/m2 of “energy out”? Where?
Not quite as 30% is reflected before it gets ‘in’. But that 5 W/m2 difference does not make any real difference in the budget at the level of accuracy of our understanding.
vukcevic says:
April 30, 2012 at 1:27 pm
It is regrettable that few of those IPCC scientists know of, and even fewer if any understand the sun – earth – temperature multi-decadal link.
This is not ‘understanding’ or even valid science as we have discussed so often before.
Gail Combs says:
April 30, 2012 at 11:47 am
“David I think Richard B Woods is this guy:
Dr. Richard B Woods
Richard leads the Climate, Cryosphere and Oceans (CCO) group in the Met Office Hadley Centre.
Richard is head of the CCO group, whose remit covers modelling the role of the oceans and ice in the climate system. In addition, CCO acts as a focal point for policy-focused science to inform climate change mitigation strategies aimed at avoiding dangerous climate change…. http://www.metoffice.gov.uk/research/people/richard-wood ”
– –
Gail,
Did you notice that the Richard Wood in the Met Office Hadley Centre does not have an “s” in his last name, while my last name does? I don’t live in the UK and have no connection to the Met Office. Why do you misspell Dr. Wood’s name as “Dr. Richard B Woods”?
Leif Svalgaard says: April 30, 2012 at 2:20 pm
This is not ‘understanding’ or even valid science as we have discussed so often before.
You can do the Antarctic delta Bz yourself (delta t =20 years).
I am sure you do understand it perfectly well, it just happens you don’t like what you see; to the delight of Usoskin, Solanki, Lockwood and other assorted luminaries, it blows the SSN revisionist science into pieces. However, I think you are correct about the Svensmark’s hypothesis, as it can be easily concluded by comparing opposing trends at the poles.
davidmhoffer says:
April 29, 2012 at 2:46 pm
“For ice to form on salt water, all the water below the surface right to the bottom must first cool to the freezing point.”
No, it doesn’t. See http://www.linkingweatherandclimate.com/ocean/waterdensity.php
or, with more detail, http://www.lsbu.ac.uk/water/explan2.html
“Nice attempt at a misdirect though. Are you a lawyer?”
I wasn’t attempting to misdirect. I’m not a lawyer.
vukcevic says:
April 30, 2012 at 2:58 pm
I am sure you do understand it perfectly well, it just happens you don’t like what you see
I see wiggles, but they have nothing to do with each other. In order to ‘not like’ something it has to make sense. If it does not, it is just thrown on the junk heap with nary a thought or dislike.
vukcevic says:
April 30, 2012 at 2:58 pm
I am sure you do understand it perfectly well, it just happens you don’t like what you see
This is what I see: http://www.leif.org/research/Field-Change-at-Poles.png
Note what happened before 1650. As I said: correlation junk.
Leif Svalgaard says:
I see wiggles, but they have nothing to do with each other. In order to ‘not like’ something it has to make sense. If it does not, it is just thrown on the junk heap with nary a thought or dislike.
An idea:
*We know that the suns main effect on warming the air is that first, it warms the water, which then warms the air.
*We know thatt here are various currents and waves (ENSO and the like) which have various timed cycles (decadal, multi-decadel etc). Specifically, we know that these different cycles have different timings, in relationship to each other, some shorter, some way longer.
*The sun goes into, say, a Grand Minimum.
*It’s main effect is to heat or not heat water differently than it did before (either directly, or through some emechanism like increased clouds resulting in increased shade). This of course assumes that anything all all different actually happens.
*If this is the way things are working, then a change in the sun will not result in a matching change in the climate, because the different simescales of all the largly water based effects of the heating will result in very diffeent timescales for any solar effected change in different areas. That is, in areas where there is no current, the change may be relatively quick, in areas with a decadal oscillation, it may take up to a decade, in areas with a multi-decadal oscillation, multi decades, etc.
*In other words, if the suns effect is indirect, modulated through various cycles that take varying lengths of time, you should expect that changes in the sun, wiggles on your graph, will not cause immediate and worldwide changes in climate, matching wiggles on a climate graph. The changes un the sun may still cause noticable changes in climate, but it could be hard to spot on a worldwide scale since the changes will show up in different places at widely varying times, and in some places the effects of corcings, feedbacks, and thermostated effects of various intensity may amplify or even entirely counteract the effects of the sun in that area. About the only thing you could see clearly might be if there is large changes by the sun (say the Maunder) and matching largish changes by the climate over a long timescale, probably at least several decades, OR, changes in some areas that are dramatic enough to be noticed in the case that some areas are not effected by the sun due to local thermostate or forcing/feedback effects.
Or to put it another way, with all the various climate cycles of various timeframes on this planet, I would actually be very suprised if wiggles seen on a graph by the sun created matching wiggles of climate. I would expect that it would take a longish period of several Grand Minimums to make a semi matching period of cooler weather, which appears to be what happened in the LIA.
Speaking of which, you say “http://www.leif.org/research/Svalgaard_ISSI_Proposal_Base.pdf If you look at Figure 2 you can see that the cosmic ray proxies have been rather constant the past 300 years. As the cosmic ray modulation is believed to be controlled by the sun’s magnetic field as drawn out into interplanetary space [the Heliosphere] the level of the cosmic rays is often expressed as the equivalent magnetic field strength [the one that would yield the observed radionuclides].
Yes, “rather constant” for 300 years, however, what about that 1700 dip? THAT was NOT rather constant, that looks large enough to have caused some climate change, was there any climate change at around that time? Note the above, the change may be different timing wise in different areas of the earth due to the effects of different timescale currents and other cycles.
And that brings me to one last point. If we are going to really solve the issue of what causes say, a Roman Warm Period, followed by a cooler Dark Ages, followed by a warmer MWP, followed by a cooler LIA, followed by the current modern warm period, and whether these are caused by periodic changes in the sun, what we need is, first, proxies that show past periods of warmth and cooling, which we have, and past periods that show changes of the suns magnetic field, which we can then look at to see if they match timeswise. Do we have proxies that go back far enough and are reliable enough to tell the suns magnetic activity during past peroids of known warmth and cooling? If they match up, we will then know that there is significant corellation between what the sun does and climate, at least when what the sun does is different enough long enough to matter. If the sun goes grand Minimum a,d every time hte earths climate cools, then it does, it will not matter whether we agree on the mechanism for it or not, if it does it, it does it. Are there such solar matgnetic proxies going far enough back, then we can at least answer that question.
If there are not, then we are stuck with a very limited, perhaps too limited, dataset to answer the question. I mean, the LIA lasted a rather longish time, and our dataset appears to only go back as far as the latter part of it, or even just to the tail end of it. That is far to small a dataset to really be sure. We would really need multiple Grand Minimums to match up with the known multiple cool peroids to really be sure. All I see right now is one partial dataset, part of a known cool period matching with part of a proxie of the suns magnetic activity.
And this of course is only the proxies we have, can we know what, say, the speed of the solar wind was 300 years ago if that speed may vary independantly of such magnetic proxies as we have? Can we be sure that the one always effecs the other, can the solar wind slow down while the proxies show only a smaller change? After all, we do not have DIRECT solar wind measurments from back then, so we really would need to know if the proxies and solar wind (and other things that may effect climate, such as changes in UV) actually always match up. I beleive it is said that it is changes in the solar wind speed and pressure that effect cosmic rays, so what we really need to know is the speed of the solar wind, which we cannot directly measure back that far in time.
SHORT FORM:
If you look for matching wiggles on solar magnetic activity and climate, you may not find them because the timings of the varoius climate cycles will throw them off. The best you can hope for is for very large (say Maunder Minimum sized changes or multiple Grand Minumums) solar changes to match longish period climate changes, lomg enough to smooth out these introduced cyclic variables. Big picture, see it, small picture, not see it.
To really see the above big picture, we would need to look back at, say, the last 10,000 years of solar and climate cycles, and see if there is a match, can we do that?
Leif Svalgaard: I have no doubt that over time, by default, more will overcome their remaining qualms until even solar history revisionism helping lead to blaming the Little Ice Age on volcanoes (not matching the timing of its start, magnitude, nor duration) or the new trend of lol BS about claiming the relatively tiny number of humans back then caused it instead of any impact of http://www.freeimagehosting.net/newuploads/319xq.jpg becomes standard, if not blaming on utter vagueness that nobody can even link to a write-up of over relevant timeframes in any real detail. Ideological polarization increases over time, as does what people feel they can get away with. But I’m not so naive as to think it matters what I say to you directly except when there are other readers as an audience, and this isn’t the best thread for most matters now since no longer on the front page.
Legatus says:
April 30, 2012 at 9:40 pm
Yes, “rather constant” for 300 years
Only “rather constant” if someone throws out every contradictory source of data, like those I previously mentioned (among really many others but as a sample):
http://chiefio.files.wordpress.com/2011/06/1000px-carbon14_with_activity_labels-svg.png?w=640
from
http://pubs.usgs.gov/fs/fs-0095-00/fs-0095-00.pdf
http://www.freeimagehosting.net/newuploads/319xq.jpg
from (plus other sources mentioned before)
http://napink.com/Global%20Warming%20and%20Phanerozoic%20Climate%20Changes_Page_17.jpg
http://www.global-warming-and-the-climate.com/images/C14-anomlies.gif
from
http://ruby.fgcu.edu/courses/twimberley/EnviroPhilo/Svensmark.pdf
Legatus says:
April 30, 2012 at 9:40 pm
I mean, the LIA lasted a rather longish time, and our dataset appears to only go back as far as the latter part of it, or even just to the tail end of it. That is far to small a dataset to really be sure.
Actually there is data beyond that.
Although not all grand minimums, there are around 5 local minimums and 5 maximums matching in
http://www.freeimagehosting.net/newuploads/319xq.jpg
(and 1 that doesn’t but not bad for a complex system with multiple influences and some random measurement errors)
Again, sources include:
http://napink.com/Global%20Warming%20and%20Phanerozoic%20Climate%20Changes_Page_17.jpg
and
http://www.drroyspencer.com/global-warming-background-articles/2000-years-of-global-temperatures/
except more exactly
http://www.ncasi.org/programs/areas/climate/LoehleE&E2007.csv
vukcevic says:
April 30, 2012 at 2:58 pm
However, I think you are correct about the Svensmark’s hypothesis, as it can be easily concluded by comparing opposing trends at the poles.
There is support for cloud cover variation (e.g. via cosmic rays) influencing temperatures which comes from Artic versus Antarctic temperature trend differences as discussed in:
http://www.space.dtu.dk/upload/institutter/space/forskning/05_afdelinger/sun-climate/full_text_publications/svensmark_2007cosmoclimatology.pdf
On a slightly different topic, also see:
http://icecap.us/images/uploads/SvensmarkPaper.pdf
Leif Svalgaard says: April 30, 2012 at 8:51 pm
…………………..
dt should be 20 years, geographic locations we can discuss some other time, they are related to the transpolar and the circumpolar currents, since it is those two that are fundamental for understanding hemispheric climate/temperature changes, rather than the geographic or magnetic poles.
http://www.vukcevic.talktalk.net/TSA.htm
http://www.leif.org/research/Field-Change-at-Poles.png
Ignoring your temperature graph, it is more than clear that now you also understand the connection , but the interpretation is a matter of your choice.
Henry Clark says: April 30, 2012 at 11:23 pm
…………..
Clouds and temperature are two components of closed concurrent positive and negative feedback loops (degree of evaporation, air circulation due to changes in atmospheric pressure, precipitation, day & night, summer & winter, etc ), any attempt to disentangle them, is unlikely to be successful.
vukcevic says:
May 1, 2012 at 1:01 am
“Clouds and temperature are two components of closed concurrent positive and negative feedback loops (degree of evaporation, air circulation due to changes in atmospheric pressure, precipitation, day & night, summer & winter, etc ), any attempt to disentangle them, is unlikely to be successful.”
Certainly they are related.
There would, of course, be an influence from solar activity variation other than the impact on cosmic rays (where Shaviv estimates the latter to be on the order of twice the effect of TSI variation with TSI varying far less in percentage terms). Cloud cover variation can be influenced by temperature changes even while cloud cover variation simultaneously causes temperature changes too. But an example of the overall picture is the graphs in the papers linked in my prior comment. It is unfortunate I can’t post images directly in comments here, as that cripples illustration.
The degree of correlation between cloud cover variation (at the appropriate altitude) and cosmic ray flux variation is still more than that for cosmic ray flux versus temperature, for fluctuations on the shortest time scales, since the latter has extra substantial influence from other factors, although the papers linked in my last comment show both. The latter paper linked shows a comparison to temperature trends in figure 2, including with El Nino deductions, although my graph of Dye 3 Be-10 cosmic ray flux versus Loethle temperature data at http://www.freeimagehosting.net/newuploads/319xq.jpg is essentially that on a 600-year timeframe (without trying such deductions for ocean variation but with them less critical for seeing the basic picture on the larger timescale).
Especially at the smallest time scales, there are some significant differences between sunspot number trends and cosmic ray flux trends; for instance, sunspot numbers in the last cycle were declining substantially since 2002 whereas cosmic ray flux didn’t start its corresponding rise much until the start of 2004:
http://www.swpc.noaa.gov/SolarCycle/sunspot.gif
http://cosmicrays.oulu.fi/webform/query.cgi?startdate=2000/01/01&starttime=00:00&enddate=2012/04/26&endtime=00:0&resolution=Automatic%20choice&picture=on
The AP index is significantly closer (as in http://www.swpc.noaa.gov/SolarCycle/Ap.gif ) but not exactly the same on the smallest time scales as can be seen.
Legatus says:
April 30, 2012 at 9:40 pm
Do we have proxies that go back far enough and are reliable enough to tell the suns magnetic activity during past peroids of known warmth and cooling?
This is about the best we have at the moment [according to traditional wisdom]:
http://www.leif.org/research/Moberg-Solanki-Correlation.png and
http://www.leif.org/research/Temperature-vs-10Be-14C.png and
http://www.leif.org/research.Global-Temperatures-2000-yrs.png
Henry Clark says:
April 30, 2012 at 11:20 pm
Only “rather constant” if someone throws out every contradictory source of data, like those I previously mentioned (among really many others but as a sample):
You are still quoting a lot of establishment graphs [most of which are not independent]. The motivation for this may be ideological, but science in the end triumphs.
vukcevic says:
April 30, 2012 at 11:50 pm
dt should be 20 years
It shouldn’t matter much what dt is, except that higher time resolution is always better. In any case you can just smooth the 10-yr curves.
Ignoring your temperature graph, it is more than clear that now you also understand the connection
I carefully showed that there is no ‘connection’ to understand.
Legatus says:
April 30, 2012 at 9:40 pm
Yes, “rather constant” for 300 years, however, what about that 1700 dip? THAT was NOT rather constant, that looks large enough to have caused some climate change, was there any climate change at around that time?
It probably was CAUSED in large part by the climate, see e.g. http://arxiv.org/ftp/arxiv/papers/1004/1004.2675.pdf
line 222 ff: “Indeed this implies that more than 50% the 10Be flux increase around [the dip in solar activity], e.g., 1700 A.D., 1810 A.D. and 1895 A.D. is due to non-production related increases”
See also slide 47 in http://www.leif.org/research/The%20long-term%20variation%20of%20solar%20activity.pdf showing that there was a well-developed solar magnetic field in 1706
Legatus says:
April 30, 2012 at 9:40 pm
Do we have proxies that go back far enough and are reliable enough to tell the suns magnetic activity during past peroids of known warmth and cooling?
http://www.leif.org/research/Global-Temperatures-2000-yrs.png
http://www.leif.org/research/Global-Temperatures-2000-yrs.png
Leif Svalgaard says:
April 30, 2012 at 1:53 pm
“Not quite as 30% is reflected before it gets ‘in’. But that 5 W/m2 difference does not make any real difference in the budget at the level of accuracy of our understanding.”
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Leif the 30% above confirms again that the reflected energy calculation is also only a rough approximation based on input and not on real measured data.
Systematic bias is systematic error in energy budget calculation. One cannot say that 0.1 W /m2 is energy imbalance when all input and output may contain systematic errors of +- 5 W/m2.
But this was OT to the blog-post.
Coming back to topic, you were saying that we can understand variances in the sun’s output by 0.007 W/m2. Sorry, this is wide overstated.
The paper itself highlights the error exceeding previous confidence statements: “This fundamental difference” – the 5 W/m2 – “exceeds prior measurements’ reported uncertainties of ∼1.3 W m−2”
Even in Lean’s paper one can see the grey area marked as uncertainty (Fig 1.b). Furthermore the paper discounts 1 W variances measured by instruments based on other proxies and models.
Whereas it may or may not be right, shows still the problems in instrumental measurements and the over reliance on models.
Only during the last decade do we really start to have real data that could measure variances closer to where the human influence could be: TIM, ARGO, Envisat, Jason2 and what we see is a lot of data that does not fit the current dogma.
Leif Svalgaard says:
May 1, 2012 at 4:10 am
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What are the error bars on your solar reconstruction in this plot?
Also, concerning the long term affect of consistently high solar activity, what is the pecentage change in the one percent spectrum of solar activity which reaches the disphotic zone? Also, what is the resdience time of that energy, and might it not be far longer then seven years? Indeed,, solar energy constitutes a rather vast spectrum, so what is the residence time within the earths ocean of each spectrum, and how much does each spectrum change over a solar cycle?
My questions pertain to OHC, others may have similar questions pertaing to atmospheric changes over long periods of time. As basic ocean cycles appear to be multi decadal, all forcings of shorter and longer duration have to be sorted through these various filters.
I suggest that the error bars on solar reconstructions is perhaps quite large. Below, (W.R. Webber1, P.R. Higbie2 and C.W. Webber3), notes how the climate can affect the 10be ice core proxy. However the problem with past climate reconstructions is that their resolution is not able to detect such fine changes. Indeed, one of the “team” membes states that as far as 100 year resolution we know xxxx-all, about climate, although I am however, not that sceptical.
Leif and others suggest that sun spot counts are a better method of determing past solar activity. This, in and of itself, is somewhat problematic, although some claim to have accurately assembled past sun spot records for several hundred years at least. To get accurate error bars on solar activity correlation to climate it appears we need error bars on both recordes, as well as the ability to determine the residence time of various solar spectrum within the earths system, particularly the oceans, as welll as greater understanding of cloud formation mechanics and jet stream movements.
The answer may be, we simply do not know the past with the accuracy necessary to determine correlations and possible causeations, and should instead concentrate on the most recent solar cycles and climate observations whrere we have much better observations.
Webber1, P.R. Higbie2 and C.W. Webber3
“155 The large scatter between the 10Be ice core measurements and 10Be production
156 calculations and the resulting lack of correlation on a year to year basis, described above, could
157 arise in several ways. Two possibilities are; 1) Severe climatic effects on a time scale ~1-2 years
158 or less (e.g., Pedro, et al., 2006). These effects could be very local or more general effects
159 covering large geographic scales. 2) “Instrumentally” based effects that somehow introduce a
160 large variability in what are more uniform variations.”
Lars P. says:
May 1, 2012 at 4:19 am
Coming back to topic, you were saying that we can understand variances in the sun’s output by 0.007 W/m2. Sorry, this is wide overstated. The paper itself highlights the error exceeding previous confidence statements
You are still confusing accuracy and precision. The systematic error is constant, thus does not influence the precision. To illustrate the difference, imagine you have a weighing scale and uses that to measure your weight every day, your loss and gains with a precision of one ounce. After a month you discover that it matters whether you have your clothes on or not, there is a three pound difference. That is the systematic error, but since it is constant [assume always the same clothes] the difference does not distort a graph of your weight loss or gains. That is the precision.
David A says:
May 1, 2012 at 5:05 am
What are the error bars on your solar reconstruction in this plot?
I suggest that the error bars on solar reconstructions is perhaps quite large.
The error bars on the cosmic ray – based recontructions are large, but can diminish in time as methods get better and many more cores are analysed.
Leif and others suggest that sun spot counts are a better method of determining past solar activity. This, in and of itself, is somewhat problematic
The sunspot number is a count and as such does not have error bars: if you count the coins in your purse and find you have $2.57, what is the error bar on that? The problem with the sunspot count for really old records [200+ years ago] is the lack of systematic counting and how to calibrate one casual observer against another.
To get accurate error bars on solar activity correlation to climate it appears we need error bars on both records
And it turns out that the climate record is less known than the solar activity record. Yet, in spite of all those errors, there are people that claim fantastic and overwhelming correlations between the records…
Leif Svalgaard says:
May 1, 2012 at 7:26 am
Coming back to topic, you were saying that we can understand variances in the sun’s output by 0.007 W/m2. Sorry, this is wide overstated. The paper itself highlights the error exceeding previous confidence statements
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You are still confusing accuracy and precision.
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Thanks Leif for the explanation on systematic errors, but you missed the part: … the paper discounts 1 W variances measured by instruments based on other proxies and models…
“Although ACRIM I, ACRIM II, ACRIM III, VIRGO, and TIM all track degradation with redundant cavities, notable and unexplained differences are evident in Figure 3a among their reported irradiance variations and in Figure 3b with the modeled influences of sunspots and faculae (shown in Figure 1c and used to estimate climate responses in Figure 2). Features not easily attributable to solar activity include an annual cycle that is nearly in phase with the Sun‐Earth distance in ACRIM III data, and 90‐day spikes in the VIRGO data coincident with SoHO spacecraft maneuvers that are most apparent during the 2008 solar minimum.
Disagreement among overlapping observations, as apparent in Figure 3, indicates undetected drifts that suggest the TSI record is not sufficiently stable to discern solar changes on decadal time scales. For example, Figure 3b shows that only the ACRIM composite shows irradiance increasing by ∼1 W m−2 between 1986 and 1996; if real, the solar origins of this increase are ambiguous since it is also absent in the model.”
Leif cites the thoroughly debunked Schwartz 2006:
I critiqued a later version of this Schwartz paper last year. Schwartz’ model is built on a single heat sink. That is, it assumes that the whole ocean warms at once and hence can be represented by measured top-water temperatures. Not that Schwartz was actually so silly as to think that this is what is really going on. He just thought that this was the right model to look at to analyze short term changes in global surface temperatures, as he explained at the beginning of his abstract:
Schwartz’ very first sentence acknowledges that heat transport into and out of deeper ocean layers can easily take centuries. For Leif to represent this paper as arguing AGAINST century scale warming and cooling of the oceans is pretty bad.
Have a good trip Leif! And if you get a chance, do point out to Solanki that rapid responses to short term forcings (which he found between solar activity and global temperature) do not militate against longer term responses to longer term forcings, but actually imply them. Really, it an absurd mistake for solar physicists to be making, and it needs to stop. This is Solanki’s excuse for claiming that the sun can’t be responsible for late 20th century warming, even though he thinks that solar activity was, up until the last couple of decades, the primary driver of global climate. He’s essentially claiming that because the day warms quickly in response to the rising sun, the planet can’t warm more slowly in response to increased seasonal insolation, and on the basis of this “science” he is willing to support that “consensus” that we have to unplug the modern world. Please call him on it! (You just may have to call yourself on it first.)
Alec Rawls says:
May 1, 2012 at 10:29 am
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I do not know why it appears so hard for some to understand the potential for greater then seven year affects of solar insolation. This is why here I earlier asked Leif, “concerning the long term affect of consistently high solar activity, what is the pecentage change in the one percent spectrum of solar activity which reaches the disphotic zone? Also, what is the resdience time of that energy, and might it not be far longer then seven years? Indeed, solar energy constitutes a rather vast spectrum, so what is the residence time within the earths ocean of each spectrum, and how much does each spectrum change over a solar cycle? Leif answered my other queations, but chose not to answer what I consider to be the most important in regard to OHC. Solar affects on cloud formation , and potentialu jet stream locations, are of course another large area of limited but growing understanding. Thank you for your posts highlighting how the IPCC chooses to inform their ignorance.