As a prelude to a new book, Nigel Calder (who was the editor of New Scientist for four years in the 1960s) has written an op-ed for the Times (UK) basically recapitulating the hype over the Svensmark cosmic ray/climate experiments we reported on a couple of month ago (see Taking Cosmic Rays for a spin). At the time we pointed out that while the experiments were potentially of interest, they are a long way from actually demonstrating an influence of cosmic rays on the real world climate, and in no way justify the hyperbole that Svensmark and colleagues put into their press releases and more ‘popular’ pieces. Even if the evidence for solar forcing were legitimate, any bizarre calculus that takes evidence for solar forcing of climate as evidence against greenhouse gases for current climate change is simply wrong. Whether cosmic rays are correlated with climate or not, they have been regularly measured by the neutron monitor at Climax Station (Colorado) since 1953 and show no long term trend. No trend = no explanation for current changes.
213 Responses to "Nigel Calder in the Times"
So funny how your dismissive attitude here toward the ideas expressed in the article mirror the dismissive attitude in the article toward your side. This is just the most recent example of this sort of thing.
I am just annoyed that no one seems to be acting grown-up in their rhetoric about this on either side. Hyperbole, alarmism, and sarcasm toward opposing viewpoints prevails on both sides, at least in terms of what the public is treated to in the popular media.
We, the non-scientist public, deserve better from both sides, if this is of such grave import.
Barton Paul Levenson says
[[So funny how your dismissive attitude here toward the ideas expressed in the article mirror the dismissive attitude in the article toward your side. ]]
Did you miss the fact that the cosmic ray people have a big fat contradiction between their theory and the evidence? Forget who is dismissive of whom, take a look at the facts.
Mark A. York says
They say there are no facts Barton. Like all of that particular social persuasion, they seem to think if you just say it, that makes it true and no support is needed. Amazing. My comment there failed to post for some reason.
I had commented on Nigel’s article yesterday (curously the page seems to show only 10 comments at a time) and basically pointed out three main problems with the argument he presented.
1) Nigel claims that the ‘cooling’ of East Antarctica contradicts the theory that greenhouse gases are causing global warming. For one – and I think RealClimate has made this clear – pointing to East Antarctica is not proof that global warming is not happening (see Davis 2005). Furthermore, how can one infer that it is not greehouse gases causing the recent warming by pointing to East Antarctic cooling, especially considering what the IPCC has already had to say about this.
2) He claims that the global temperature rise reached a plateau in 1999. So far, what I have seen shows the contrary: that it has continued to rise.
3) The argument is based to a large degree on political arguments, rather than scientific analysis. In other words, it is purported that the claim that anthropogenic global warming in recent times is a real and dominant phenomena is weakened because it’s the orthodox position, or it’s somehow not open to new interpretations and theories, and so on. These are arguments from a given political circumstance, not from quantitaive/ qualitative analysis of data.
Paul M says
Now the bees are dying. Is there any link between the decline in the bee population and climate change? We need those little critters to pollinate the plants.
Hank Roberts says
>is there any link ….?
Er, probably (wry grin). I’m commenting as another reader here (who did keep bees once), I’m not a climate scientist.
Ask locally if you’re seeing a local problem. There are changes due to climate and weather. There are far greater risks for honeybees (one of hundreds of kinds of bees, which are among dozens if not hundreds of kinds of pollinators).
Got pesticide spraying? Migratory beekeepers? A good bee inspection system in your state watching out for known bee diseases that enforces laws to control them? (Ohio had a very effective bee disease control, decades ago at least; I don’t know of many other good ones.)
If you’re talking honeybees, remember they’re European imports; the natives here called them the “white man’s flies” when they arrived. And if you’re talking native pollinators, remember you’re talking about far more animals besides honeybees.
Steve Latham says
I’m surprised by two things in the article: 1. when he states that researchers who have contrary ideas or evidence are rewarded with impediments to their careers (is Svensmark and his basement his only evidence?), and 2. when he mentions solar physicists in general with no name or organisation or anything. I’m surprised because I would expect a former editor of a science mag to reference evidence for such statements and I’m disappointed that he didn’t.
Dennis Wingo says
So I guess that this graph, linked from the same NOAA FTP site is also a poltical ploy
Very good picture of how total solar energy has been increasing.
Data does not lie
The blogosphere is all abuzz with the reports of galactic cosmic rays. Many seem to think it’s is a new, revolutionary idea, as though we hadn’t known about this for years. What surprises me most (well, actually it doesn’t) is that skeptics are so highly critical of any perceived flaw in the IPCC AR4 SPM, but so eager to embrace (without critical appraisal, or even any appraisal at all) an alternative which has no observational support and a most flimsy theoretical basis.
It’s also very revealing that skeptics constantly harp on the idea that alternative viewpoints are “shut out of the discussion.” Nothing could be further from the truth. Svensmark’s theory, though not really credible, still made its way to publication in the peer-reviewed literature, experiments are now scheduled to study the effect of GCRs on cloud condensation nuclei, and both the blogosphere and the media are making (much too much) a big deal of it. How is this being “shut out” of the discussion?
gerald whyte says
Re post 8 I think your link should be
[Response: Indeed, please look at the time scale- this is just the upswing from solar minimum to solar maximum. To see how that really fits in on the longer time-period, look at the PMOD composite:
Jim Cross says
My understanding is that the Sun has been more active magnetically for the last 150 years.
How does a a baseline begun in 1953 disprove anything?
The Sun was more active during the Medieval Warming and less active during the Little Ice Age. Surely, the Medieval Warming and the Little Ice Age aren’t explained by the rise and fall of green house gases. So, unless some one offers a better explanation, these events seem best explained by variations in solar output and/or the magnetic field.
If that is right, then a more active sun would probably have SOME effect even if it does not account for all of our current warming and even if its exact mechanisms are not completely understood.
[Response: Nobody’s saying the sun has no effect. Many of us at RC have published papers on observational and modelling evidence for solar forcing effect on climate. The point of contention which always seems to come up is whether it has anything to do with the current climate change (i.e. the last few decades). The answer there is no (or more precisely, not very much). -gavin]
Hank Roberts says
Dennis Wingo: data does not lie; it wants to be understood. The graph you point to shows a change from about 1365 to around 1367, with a lot of variability. If it were your average bank balance per month, or Stairmaster average steps per day, would you think you saw a trend with that kind of change and variation?
Pollinators: honeybee colony collapse disease news:
Jim Cross says
Re #11 Gavin’s comment
Some where there was link to an article(s) that attempted to measure the effect of solar variation on recent warming. This was article that concluded it wasn’t having much of an effect. Could somebody point me to it?
I can’t remember how the analysis was done but, given that solar variation may have accounted for much of difference between the Medieval Warming and the Little Ice Age, I wonder if it might be underestimating a little.
Walt Meier says
The Antarctic sea ice numbers are misleading if not completely wrong. See http://nsidc.org/data/seaice_index/ for the specific numbers.
The only month you can get an 8% increase since 1978 is in March. Feb, Apr, and May give you ~6%. The other months are 3% or less (and December is actually decreasing slightly).
Meanwhile, in the Arctic, the annual mean has decreased by over 10% overall, and summers have declined by over 20%. And most importantly, while the Arctic trends are statistically significant at a 99% level, the Antarctic trends are not even significant at a 90% level.
Dennis, the graph you reference only covers four years — less than half a solar cycle. Have a look at this graph.
Data does not lie. But showing only a tiny fraction of the data so that it will support your hypothesis…
Hank Roberts says
PS, New Scientist’s editorial weblog — defending a recent article on a ‘reactionless drive’ — wrote:
“… should New Scientist should have covered this story at all? The answer is a resounding yes: it is, after all, an ideas magazine. That means writing about hypotheses as well as theories….”
If I go directly to the VIRGO page (I’m a theoretical astronomer who constructs solar models) I get to
and I go to total solar irradiance, the relevant place is Figure 2.1 to get the variations in the solar flux.
Nothing much is happening, although there is interesting structure even at small luminosity contrasts.
Your link is broken, by the way; I did eventually find your image, which is taken from one small section of VIRGO data with a 3 year baseline.
Yes, the solar luminosity does vary over a solar cycle, which is longer than 3 years. However, if you
look over longer periods than that (as per the links above) these cycles average out and are too small.
Data doesn’t lie, but people can either misunderstand or misinterpret data. Why did you pick a three year snippet
instead of the more easily found 25-30 year timelines? Because the former shows a linear trend and the latter does not?
That sure is a brief commentary on Svensmark’s work. You fail to point out that the Climax Station does not measure all cosmic rays, only those in certain energy ranges, which are not the optimum ranges for cloud nuclei formation.
[Response: We’ve done this to death, and sometimes we get bored too. If the argument is that cosmic rays are being modulated by the solar activity (which they clearly are on a 11 yr timescale), then I don’t see any reason why different energy bands will be trending differently than the ones monitored at CLIMAX. I would also point out that this is the same series used by Svensmark and others to demonstrate a cloud link in the first place. -gavin]
Gaudez Mischol says
Link doesn’t work.
Steve Latham says
Nitpicking: data -> plural; datum -> singular
Ike Solem says
As an example only…
Global warming: another experiment that demonstrates that increases in atmospheric CO2 will not have any effect on climate…
“Researchers recently carried out an experiment that debunks the central point in the ‘theory’ of global warming. They constructed an experimental model of the atmosphere in a box, and by passing infrared light through this model, they demonstrated that the atmosphere is already saturated with respect to the absorption of infrared light by carbon dioxide. In layman’s terms, this shows conclusively that adding CO2 to the atmosphere will have no effect on the net absorption of infrared light, and thus will not increase the surface temperature of the planet. Global warming has been shown to be a hoax!”
Hope noone takes that seriously, and decides to publish it on the front page of the Wall Street Journal…
I suppose I should include the actual series of events related to that experiment: see http://www.aip.org/history/climate/co2.htm
A few years after Arrhenius published his hypothesis, Knut Angstrom sent infrared radiation through a tube filled with carbon dioxide. He put in as much of the gas in total as would be found in a column of air reaching to the top of the atmosphere. The amount of radiation that got through the tube scarcely changed when he cut the quantity of gas in half or doubled it. The reason was that CO2 absorbed radiation only in specific bands of the spectrum, and it took only a trace of the gas to produce bands that were “saturated” – so thoroughly opaque that more gas could make little difference.
This was all clarified around 1950:
The early studies sending radiation through gases in a tube had an unsuspected logical flaw – they were measuring bands of the spectrum at sea-level pressure and temperature. Fundamental physics theory, and a few measurements made at low pressure in the 1930s, showed that in the frigid and rarified upper atmosphere, the nature of the absorption would change. The bands seen at sea level were actually made up of overlapping spectral lines, all smeared together. Improved physics theory, developed by Walter Elsasser during the Second World War, and laboratory studies during the war and after confirmed the point. At low pressure each band resolved into a cluster of sharply defined lines, like a picket fence, with gaps between the lines where radiation would get through.
As far as the cosmic ray question, one there’s no trend, two there’s no evidence that cosmic rays would increase CCN formation in the atmosphere (as opposed to inside a smoggy box) – see http://rabett.blogspot.com/2006/10/svensmark-stumbles-into-smog-chamber.html , etc. It’s already been rebutted several times… but here we see it again! Incidentally, people were claiming that the above ‘CO2 experiment’ disproved global warming on RC threads about six months ago.
Re: #10 Gerald, thanks so much for the link to those solar graphs. They will be helpful in my presentations.
What is the current RC explanation as to why the NH is warming and Antarctica is cooling? The cloud cover theory seems to explain it. Does RC have a different explanation besides cloud cover? Do you disagree that cloud cover can explain it?
[Response: RC search in the upper right corner of the main page is your friend here. A search on “Antarctic cooling” takes you right to our previous post Antarctic cooling, global warming. -mike]
Re #20: “Nitpicking: data -> plural; datum -> singular”
If you’re writing in Latin, sure. In normal English usage, though, data is a mass noun (I think that’s the correct term, though it’s been a while since I studied English grammar, or Latin), used to refer to a whole collection of stuff – like for example snow or sand. So put that nit back :-)
Collective is the word you are looking for. Data is a collective noun. Like sheep.
I have seen Nigel Calder speak and I am surprised at his op-ed. As written, his op-ed inidcates he is more or less ignorant of the basis of the IPCC findings and the scientific consensus on global warming. Cherry picking at its best!
gavin: did you ever finish May discussion ( https://www.realclimate.org/index.php/archives/2006/05/thank-you-for-emitting/#comment-13470 ) with Nir Shaviv?
Ike Solem says
RE#23 – There are certainly a lot of recent scientific reports on the Antarctic that you might want to look into.
First, consider the tropical glacier record, which includes evidence of the Medieval Warm Period and the Little Ice Age as well as the last 50 years of unprecedented warming; the compilation of global tropical glacier records is discussed at:
“First Compilation Of Tropical Ice Cores Shows Abrupt Global Climate Shifts” Jun 27 2006
Thus, the warming is not confined to the Northern Hemisphere, but is a global phenomenon.
The Antarctic cooling issue (as cited in the linked op-ed) is a good example of How Misleading Talking Points Propagate (RC) – that may be the link you’re looking for.
Note also that overall Antarctic snowfall has not increased in 50 years.
“First Direct Evidence That Human Activity Is Linked To Antarctic Ice Shelf Collapse” Oct 16, 2006
“Antarctic Ice Shelf Collapse Triggered By Warmer Summers” Jan 19 2001
“Rapid Temperature Increases Above The Antarctic” Mar 30 2006
“Antarctic Ice Shelf Retreats Happened Before” Feb 28, 2005
“Antarctic Ice Sheet Losing Mass, Says University Of Colorado Study” Mar 2, 2006
“Climate Changes Are Linked Between Greenland And The Antarctic” Nov 10 2006
“Antarctic Ice Shelves Breaking Up Due To Decades Of Higher Temperatures” Apr 9 1999
“Study Previews Ice Sheet Melting, Rapid Climate Change” Mar 12 2006
And so on… the take home message seems to be that both rising ocean temperatures and summer air temperatures can have dramatic effects on ice sheets, and the Antarctic ice shelves are sensitive to ocean temperatures (which control the melting rate) and snowfall/ ice flow (the addition rate). As the shelves go away, the glaciers will flow right into the sea. The Medieval Warm Period and the Little Ice Age seem to indicate that the climate is sensitive to various forcings, and we’ve created an unprecedented and increasing atmospheric CO2 forcing due to the use of fossil fuels – estimated to be ~20X that of any potential solar forcing – so we should expect that the observed warming trends will continue. Also note that most of the above papers weren’t discussed in the 2007 IPCC report – too recent.
Fabien Bulabois says
Re New Scientist/Nigel Calder, former editor of:
Just highlighting the difference in tone between New Scientist No 2569, 16 September 2006: GLOBAL WARMING – Will the sun come to our rescue?, and the latest issue No 2590, 10 February 2007: GOODBYE COOL WORLD – WHY OUR FUTURE WILL BE HOTTER THAN WE’VE BEEN TOLD. It may be a case of judging the book by its cover, but the second statement is a lot more assertive in its form (exclusive use of capital letters) and content (affirmative mode).
Jon-Erik G. Storm says
You will not resolve these disputes with contrasting sorts of data, because there will always be some contradictory evidence for any theory.
Of good help is a little history, and a little meta-science, or a look at scientific method.
Implicit in most of these articles is that because global warming has become the orthodoxy, it brooks no dissent. To prove this, every once in a while, we read some new data set that “contradicts” the whole theory.
This happens all the time. A good example is that Newton’s theory of gravity was not able to precisely model observations of the path of Mercury beyond a certain degree of accuracy. In the end, one of the experiments seen as confirming Einstein’s theory was that it did in fact track Mercury precisely.
But in the meantime, Newton’s theory was not thrown out in toto because of a few flaws. Instead, it was refined.
Here, the idea that science is nothing more than a sort of pyrrhonian skepticism is simply wrong. Science accepts tested theories as a model of truth, not to be discarded without a more compelling, fully working model.
Until the so-called skeptics of global warming can present a model that fully explains all of the observations, they have nothing.
The best they could really hope for is to limit the anthropogenic percentage, but in the end, as long as there is any anthropogenic contribution, there needs to be man-made counter-actions.
Another way to hit home with these (often works with evolution deniers) is to ask if they want their medicine conducted on these breaking shreds of evidence without competent review and long term study.
S. Molnar says
1. I won’t debate the unpleasant subject of normal English usage, but in scholarly writing the distinction between “datum” and “data” has not disappeared, both because some of us prefer to use Latin words correctly and because it is useful to be able to differentiate between the singular and plural forms.
2. Speaking of differentiation, “the Times” is ambiguous (yes, I know I can follow the link, but I try not to follow too many Murdoch links), especially when the author’s nationality (“group”) is unknown.
3. (Re mike’s comment) I don’t wish to complain about the enlarged search function, since that might be viewed as volunteering for webmaster duties, but I was more inclined to scold people for not using it back when a compound search was not required to restrict the results to RC.
4. Please give us a straight science entry soon – absence has made the heart grow quite fond enough, thank you.
[Response: The UK Times. I’ve edited above to be clearer. If you want to volunteer for websmaster duties, I need someone to program in a branch to each search function from two radio-buttons nicely placed in the above banner. Any and all offers accepted and I’ll send you the details on request! -gavin]
Jeff Weffer says
What seems completely implausible is that variations in solar activity have no impact on Earth’s climate whatsoever.
They obviously do, since virtually all (99.9999%) of Earth’s climate is derived from solar energy.
The next issue is that it is completely implausible that solar activity is a monolith, never changing amount. The Sun clearly has cycles of activity.
The Sun clearly has an 11-year cycle. The variance is very small between those cycles but the fact remains that old Sol is a variable entity.
What other cycles does old Sol have beyond the 11 year one. Well go back to the sunspot figures of the late 1600s if you want evidence that old Sol has more varibility than the minimal variance of the 11 year cycle.
What bothers me the most, is that people will go out of their way to discount the variation when the evidence is right there. No one measured total solar irradiance in the late 1600s. So we don’t really know that solar variability caused the Little Ice Age.
We do know, however, that changes in the Earth’s orbit can translate into changes in solar energy impacting the Earth which can cause Ice Ages etc.
What bothers me the most, is that people do not want to investigate this variability any further. And some proxies such as C-14 production indicate old Sol has alot of variability, enough to explain the Medieval Warm Period, the Little Ice Age, the Modern Warming etc.
[Response: Why do you think any of what you said is controversial? Look at my own papers for ample evidence that people are actively researching these issues (most recently, Shindell et al 2006). The reason we are critical here of some of the solar shennanigans is the misuse and logical fallacies that seem to abound whenever solar is discussed. Add in the sorry history of people seeing solar connections where there are none (over and again), you have a situation where, in order to be taken seriously, you have to be extremely scrupulous in doing solar research. Svensmark and colleagues haven’t been, and they have been rightly criticised for hyping their results. As a consequence, it becomes harder to take them seriously. For that, they have only themselves to blame. -gavin]
re: your response to #23
That link says we need to be careful about short records and instead look for long term trends. May I ask: what is long term? 50 years? 100 years, 1000? 10,000? Is ~150 years of thermometer data enough to pick a trend? Is it still enough when we know that we started in a cold period? What of the coverage? What of the accuracy? You don’t want to be fooling yourself with incomplete data, do you?
Al Bedo says
The good thing about the GCR theory is that it if NASA is correct about the cycle 25 slowdown,
GCR climate impact should be very testable within 15 years:
John Tillman says
Re. Comment 18:
We need to know more about Galactic CR fluxes. The CR Isotope Spectrometer aboard the ACE satellite has for instance been collecting data at the L1 Point for less than ten years.
It may be that neutron monitoring on earth doesn’t provide the information required to establish a trend. It’s possible that a stonger solar magnetosphere preferentially shields the planet not only from certain energies but even elements & isotopes.
Neutrons are along for the ride with the protons in their nuclei, so may or may not be a valid indicator of the charged particles that actually make it through magnetic diversion, the ionosphere & stratosphere to the lower troposphere.
I hope the Danish team attempts to answer the questions you raised as steps in proof last year. The experimental work at CERN indicates they see the need to try in at least some cases.
A Question says
Off Topic, quick question:
What are your opinions (Gavin, David et al.) of Ahilleas Maurellis’ article from a few years back? I tried to research some commentary on it but could not find any…http://physicsweb.org/articles/world/16/5/7/1
Thanks, I love your site!
[Response: Mostly ok. There are a few odd statements (such as “Crude calculations suggest that the two effects approximately balance each other, and that water vapour does not have a strong feedback mechanism in the Earth’s climate” – don’t know where that comes from). However, the main hook, that there is ‘anomalous clear-sky absorbtion’ of solar radiation is no longer a big issue. As far as I recall, the anomaly was mostly associated with aerosol species rather than water vapour exotica. However, there are always ongoing improvements to the HITRAN database with respect to water vapour and so I wouldn’t want to be too dogmatic. -gavin]
Craig Allen says
Re 33: Like you I’m a non-climatologists getting my head around all this. It’s a very complex field being addressed by hundreds of scientists who have created a vast body of evidence and interpretation. As will become clear if you look around the articles on this site and elsewhere; readings from the network of thermometer stations around the world are but a small portion of the data being collected, interpreted and used to model the planet’s climate system. And temperature is only one of many interrelated parameters or relevance. Many of the data sets that they are working with go back thousands, hundreds of thousands or even millions of years. Such data are derived from myriad sources including the analysis of the chemistry and structure of layers in polar ice cores, lake sediments, tree rings, stalactites and many many others. The international consensus on what the climate is doing is based on all this and much more, all fitted together to create a coherent picture of what the climate has done, is doing and is likely to do. The picture is not complete and is not perfect, and there are plenty of pundits on the sidelines trying to muddy the picture. But it’s fascinating to watch the climatologists at work, as they polish their theories, incorporating and taking advantage of the flood of new data. Check out the rest of this web-site. It’s really worth trying to get your head around it all.
jd will says
Following the GCR debate with great interest. A few questions:
1. Is it the RC view that Solar is essentially an 11 year cycle and that its longer cycles are essentially constant or minimal contrasted against GHG forcing?
[Response:No. There is clearly an 11 yr cycle of small amplitude, and there may be longer term irradiance variations – but there is no positive reason to think they are much larger. In the past, solar forcing may have been important (along with volcanic) on multidecadal to century timescales, however, GHG forcing over the last 50 years dwarfs any concievable solar contribution. -gavin]
2. Is any group trying to reconcile Milankovitch projections (which according to my limited knowlege never fully explained the data previously) in light of new understanding of GCR, i.e., Solar Attenuation?
[Response: I have no idea how these things could be connected. Orbital variations are very well understood and there is no reason to think that GCR changes should be affected by them.]
3. Can GCR be thought of as a stream that could have the analogy of swirls and eddies due to other solar bodies?
William Astley says
In reply to response: [Response: We’ve done this to death, and sometimes we get bored too. If the argument is that cosmic rays are being modulated by the solar activity (which they clearly are on a 11 yr timescale), then I don’t see any reason why different energy bands will be trending differently than the ones monitored at CLIMAX. I would also point out that this is the same series used by Svensmark and others to demonstrate a cloud link in the first place. -gavin]
Planetary cloud cover can and is being reduced by the process “electroscavenging” which can and has occurred without modulation of GCR. (i.e. No change in CLIMAX, but planetary cloud cover is reduced.)(GCR creates ions which form the nucleous for cloud particles. Electroscavenging clears the cloud of the Ion-mediated Nucleous and causes rain.)
Electrosavenging is increasing due to an increase in the Global Electric current. The Global Electric current is increasing due to “the increased number of high speed streams of solar wind, that are occurring during the declining phase and minimum of sunspot cycle in the last decades.” (The solar southern coronal hole is moving towards the solar equator at the end of the solar cycle. The polar coronal hole is producing cyclic strong solar winds.)
It is a fact that overalll planetary cloud cover has been reduced from 1993 to 2003. See Palle’s attached paper which notes the cloud data is consistent with process “electroscavenging” and refers to Tinsley and Yu’s paper. Palle has written a second paper which use data from earthshine (reflected off of the moon) rather than satellite data which confirms this paper.
(See Tinsley and Yu’s attached paper, sections 5 a-e for details concerning the Global electric current and electroscavenging.)
Does this make sense? Two separate processes. GCR which creates ions, the ions created cloud nucleous and a separate process that clears and collects ions, hence forming rain.
[Response: ??? Try reading the papers you cite – Palle: “However, there is no clear systematic trend [in the ionization] since the 1960s.” (figure 7 caption). This is exactly what one would expect given the lack of trend in CLIMAX. If there is no trend in the input, you can’t get a trend in the output, whatever the mechanism! – gavin]
William Astley says
In reply to “2. Is any group trying to reconcile Milankovitch projections (which according to my limited knowlege never fully explained the data previously) in light of new understanding of GCR”
Yes. The hypothesis is that earth’s magnetic field is modulate by the orbital cycle. The cyclic variations of the earth’s magnetic field cyclically modulates GCR which increases or decreases overall planetary cloud cover, which creates the ice age cycle. Also it is hypothesized that GCR cyclically changes in overall magnitude as the solar system moves through the Milky Way’s spiral arms.
[Response: You might want to ask yourself why this paper never made into the peer-reviewed literature. What is more likely – that the deposition 10Be is affected by climate changes associated with the ice ages (for instance Field et al, 2006 might be useful in assessing that), or that geomagnetic modulation of cosmic rays just happens to be coincident with Jun 60N insolation? (Bard and Frank, EPSL, 2006 is also another good source for why this is rubbish). -gavin]
William Astley says
I do not understand your response: [Response: ??? Try reading the papers you cite – Palle: “However, there is no clear systematic trend [in the ionization] since the 1960s.” (figure 7 caption). This is exactly what one would expect given the lack of trend in CLIMAX. If there is no trend in the input, you can’t get a trend in the output, whatever the mechanism! – gavin]
The affect is due to an increase in the Global Electric Current, not GCR. What input at Climax are you referring to? The ions are still being produced. The electroscavenging process is removing them.
From Palle’s paper “Another explanation may be other climatic parameters are acting on cloudiness in addition to atmospheric ionization. A clear decreasing trend over approximately the past two decades is seen in both the total cloud amount … and low level cloud data. A simple linear fit to the yearly low cloud data has a slope of -0.065%/yr. If the this trend is subtracted from the low cloud data the correlation coefficient rises from 0.49 to 0.75, significant at the 99.5% level.
[Response: No trends in cloud cover are statistically significant given the uncertainties in the data and systematic issues with the satellite measurements. Why do you think there is an increase in ‘electroscavenging’? And what do you think is driving it? -gavin]
John Tillman says
I don’t know if this 2004 simulation finding climate change correlations with CO2 concentrations and GCR fluxes during the Paleozoic, Mesozic & Cenozoic has been cited yet. Haven’t read the whole article, so don’t know how the author derived inputs, to include cloud cover.
John Tillman says
It’s all about the muons:
Edward Barkley says
Are Milankovitch Cycles and other orbital variations of the earth commonly factored in to AGW climate models? Without a better understanding of cosmic radiation, I would imagine these variables are considered statistically insignificant, yes?
Peter Sutton says
Can anyone answer these questions, simply?
The Little Ice Age – real or not?
The lack of sunspots at the same time – real or not?
Is it a coincidence – yes or no?
Jim Roland says
Re: #34 Al Bedo,
Hi, I’m GW-ish.
Re: Ice Ages
There seems to be some suggestion that galactic cosmic rays are a root cause of ice ages, are modulated by earth’s orbital variations, related to Milankovitch cycles, etc.
The climate effect of orbital cycles has to do with the amount of solar energy intercepted by earth, not the output of the sun, and says nothing at all about variations in the sun.
Understanding the impact of astronomical cycles on paleoclimate is a rapidly advancing field, and our understanding of it is attaining a level of maturity which is very impressive. Those who know the details of the effects of orbital cycles cannot take seriously the suggestion that their impact is through modulation of GCRs. Those who suggest that such a phenomenon is real, cannot possibly have an understanding of the effect of orbital cycles on the distribution of solar energy.
This is yet another example of throwing out an interesting idea, which seems plausible until you actually learn something about the phenomenon. It reminds me of one of the most famous pseudo-science books of all time, Velikovsky’s Worlds in Collision, which attempted to explain world-shaking biblical events (like the plagues Moses brought upon the Egyptians) by astronomical events. It all sounded extremely convincing to those who were ignorant of the topics, but to those in the know it was pure fantasy, and not even very good fantasy. Astronomers would typically say “The biblical archeology was very impressive, but the astronomy is utter nonsense,” while archeologists would typically say, “The astronomy was fascinating, but the archeology is utter nonsense.”
For those who are interested in a few details of the effect of astronomical cycles, I’ve posted about the topic on my blog here and here.
Patrick Cassen says
Re: Global dimming. Does Stanhill’s Forum piece (EOS 88,p 58, 2007) require any response from RC (beyond what I was able to find in previous posts?) He’s claiming a total 20 W/m^2 for 1958-1992. He does not mention the “urban effect” reported by Alpert et al (GRL 32, L17802, 2005); is that the issue?
The fastest orbital (Milankovitch) cycle affecting climate is the precession cycle, with a period never shorter than about 19,000 years. That’s much to slow to affect climate significantly on century-long timescales. Therefore their effect can be safetly ignored in AGW climate models.
Why no, the people doing this work are totally unaware of such things!
That’s your basic point, yes? That scientists trying to understand AGW are librel, perhaps even commie, conspiracy people who don’t actually pay attention to stuff that appears in undergrad science textbooks.