Discussion > Best evidence: The story so far.
What I always wondered was just how much atmospheric water vapour at any time is just waiting for a condensation nucleus? It looks like clouds can form whenever they want to. Is there a significant amount of WV which can't form clouds in the absence of nuclei? That part of the mechanism needs to be scaled too, or Svensmark just has an interesting story. Now, how would you go about looking for smoking gun proof? I think there is enough to say you have proof of concept and some sort of correlation.
Well I am easily persuaded of the possibility of conspiracy and so the fact that CERN is an EU thing plus knowing how they would welcome a verdict supporting Svensmark, I think I know why a final result from the Cloud experiments has not yet been published.
Two specific findings included in the first report on Cloud:
On 25 August 2011, the first result of the experiment were published. They show that vapor traces, assumed until now to account for aerosol formation in the lower atmosphere can explain only a tiny fraction of the observed atmospheric aerosol production. The results also show that ionization from cosmic rays significantly enhances aerosol formation.
A paper critical of Svensmark was published by Lockwood and Fröhlich, in response Svensmark said:
Later in 2007, Svensmark and Friis-Christensen brought out a Reply to Lockwood and Fröhlich which concludes that surface air temperature records used by Lockwood and Fröhlich apparently are a poor guide to Sun-driven physical processes, but tropospheric air temperature records do show an impressive negative correlation between cosmic-ray flux and air temperatures up to 2006 if a warming trend, oceanic oscillations and volcanism are removed from the temperature data. They also point out that Lockwood and Fröhlich present their data by using running means of around 10 years, which creates the illusion of a continued temperature rise, whereas all unsmoothed data point to a flattening of the temperature, coincident with the present maxing out of the magnetic activity of the Sun, and which the continued rapid increase in CO2 concentrations seemingly has been unable to overrule.
Dung
Neither solar activity nor the hypothesised solar-GCR-cloud effects can be used to explain recent warming. Since none of the various papers I've linked in this discussion appear to have conveyed this, here is the back of the envelope version. The green line is sunspot number (SSN); the red is GAT.
BBD
We are both unwanted denizens on BH, you might be a little more friendly ^.^
Wow, BBD! You mean it is possible to discount a whole theory involving cosmic rays, high enegry particles etc. just be eye-balling a simple untransformed graph relating sunspot number to GAT? really?
Note that I am not saying solar activity IS related to recent warming - simpy marvelling at the audacity of your BS.
BBD
OK we have a problem here; The paper I referenced back in the good old days when we were allowed to discuss science on the communications thread was:
Long-term Variations in Solar Activity
and their Apparent Effect on the Earth's Climate
K.Lassen
Danish Meteorological Institute, Solar-Terrestrial Physics Division,
Lyngbyvej,100, DK-2100 Copenhagen (2), Denmark
You now reference a paper that shows no correlation at all.
Without saying anything else; clearly one must be wrong.
Ah now I notice that your reference is not to a paper is it?
I thought I would re-read what Nigel Calder had to say about Svensmark's most recent mega-theory:
In Svensmark’s new paper an equally concise theory, that cosmic rays from exploded stars cool the world by increasing the cloud cover, leads to amazing explanations, not least for why evolution sometimes was rampant and sometimes faltered. In both senses of the word, this is a stellar revision of the story of life.Here are the main results:
The long-term diversity of life in the sea depends on the sea-level set by plate tectonics and the local supernova rate set by the astrophysics, and on virtually nothing else.
The long-term primary productivity of life in the sea – the net growth of photosynthetic microbes – depends on the supernova rate, and on virtually nothing else.
Exceptionally close supernovae account for short-lived falls in sea-level during the past 500 million years, long-known to geophysicists but never convincingly explained..
As the geological and astronomical records converge, the match between climate and supernova rates gets better and better, with high rates bringing icy times.
Presented with due caution as well as with consideration for the feelings of experts in several fields of research, a story unfolds in which everything meshes like well-made clockwork. Anyone who wishes to pooh-pooh any piece of it by saying “correlation is not necessarily causality” should offer some other mega-theory that says why several mutually supportive coincidences arise between events in our galactic neighbourhood and living conditions on the Earth.
An amusing point is that Svensmark stands the currently popular carbon dioxide story on its head. Some geoscientists want to blame the drastic alternations of hot and icy conditions during the past 500 million years on increases and decreases in carbon dioxide, which they explain in intricate ways. For Svensmark, the changes driven by the stars govern the amount of carbon dioxide in the air. Climate and life control CO2, not the other way around.
and this
A mark of a good hypothesis is that it looks better and better as time passes. With the triumph of plate tectonics, diehard opponents were left redfaced and blustering. In 1960 you’d not get a job in an American geology department if you believed in continental drift, but by 1970 you’d not get the job if you didn’t. That’s what a paradigm shift means in practice and it will happen sometime soon with cosmic rays in climate physics.Plate tectonics was never much of a political issue, except in the Communist bloc. There, the immobility of continents was doctrinally imposed by the Soviet Academy of Sciences. An analagous diehard doctrine in climate physics went global two decades ago, when the Intergovernmental Panel on Climate Change was conceived to insist that natural causes of climate change are minor compared with human impacts.
Don’t fret about the diehards. The glory of empirical science is this: no matter how many years, decades, or sometimes centuries it may take, in the end the story will come out right.
So it's not simply solar activity governing the incidence of high energy particles - it's also the changing rate of supernova activity in relative proximity to the earth that has an effect.
Too many supernovae explosions and life becomes threatened with extinction from extreme cold, too few and regions of the earth become highly inhospitable because of extreme warmth.
Solar activity acts only as a modulator to the incidence of high energy cosmic particles, and sun spots are only a proxy for solar activity.
Matthu
Yes, the sun's magnetic field (solar wind) deflects a proportion of the particles away from the Earth when it is strong but less so when it is weak.
So the intensity of cosmic rays entering our atmosphere is controlled by:
The strength of the solar wind.
The distance from the Earth to the sun (orbital)
Our position in the galaxy (in a spiral arm close to spernovae or in deep space with weak cosmic rays)
According to Svensmark we are currently on the edge of a spiral arm and "about to leave it" meaning a long period of warmth. I dont know the timescales so we may still return to ice age one more time but somehow I doubt it.
Another notable point is that with Svensmark's theory there does not seem to be the same reliance on positive feedbacks to explain drastic alternations of hot and icy conditions during the past 500 million years, so perhaps this will be comforting to BBD - I know he was concerned that there should be an alternate explanation.
And another notable result - which goes some way to countering BBD's homemade graph he presented at Jul 26, 2012 at 9:41 PM - is this
It is evident in Figure 2 that for the 22-year period from 1983 to 2005, the average amount of low-level cloud follows the flux of cosmic rays very closely. In fact, Svensmark claims that the correlation coefficient is 0.92, a very high correlation for this type of data.A potential change in cloud cover of 3-4 percent caused by changes in cosmic ray flux is sufficient to explain global temperature changes of several degrees due to the change in the reflectivity of clouds. The reason the variation in direct radiation from the sun was rejected earlier is because it has been found to vary only by a few tenths of a percent. This is insufficient to explain observed global warming.
matthu, Dung,
Please refrain from posting this off-topic stuff. This is supposed to be a discussion of the best evidence for AGW, not the best evidence against it. (-;
matthu
Since the one thing that the climatologists do admit they have trouble modelling is clouds and since there is still (whatever BBD might say) a debate about whether any positive feedback from increased water vapour is modified by the increased cloud cover which must (inevitably, surely) follow, it is surprising that this possible hypothesis is not only not being explored but is being dismissed by mainstream climatologists without, as far as I can see, much consideration being given to looking seriously at it.
Given the .92 correlation between cloud and cosmic rays (always bearing mind that correlation is not causation) it would at least seem to drill a hole in the "it must be CO2 because nothing else works" argument.
Since this appears to work and lets CO2 off the hook is there other than a scientific reason why the establishment don't want to know?
Just askin'.
Matthu
In terms of the feedbacks; Richard had me go look at some papers that "prove" that the downward radiation and outward radiation is as predicted by the GHG theory. The only problem is that the earth does not appear to be aware of that and is not currently warming ^.^
Just as in the ice core records there are long periods where CO2 rises and temperature falls.
Just one of these events should be enough to disprove the GHG theory.
Aidey
You are a bad baaaad man ^.^
I have no problem with Svensmark being considered here in terms of qwhat would be a solid indicator that he is right and that GCRs are a major player. But it would not tke CO2 out of the picture. The CO2 GHE still exists. Svensmark provides an additional mechanism sometimes conflicting and sometimes in concert with CO2. And of course the feedback if large and positive will also work backwards. The feedback the warmists claim is temperature-related, it does not require that temp to have risen because of CO2, any reason will do. Right now we may be seeing just that, an ocean-circulation temp drop wiping out any CO2 effect AND its feedback. Now, somebody with an open mind needs to formulate an experiment which will actually prove something and measure. Did I mention that I do not trust climate scientists to do that and publish results which do not match their theory? What do you think would happen in the corridors of UAE if somebody came along and said, 'look chaps, we seem to have got it wrong'? Would they take another look, or close the experiment down? And at the met, with their cosy funding arrangements and NGO links and academic network?
What has it got to do with the United Arab Emirates??? -.-
Rhoda, you're treading a path a lot of us have done before (although with a lot more clarity and cutting logic than most) and you've arrived at the same destination. There is no empirical evidence unless you want there to BBD. There are no disastrous consequences unless you want there to BBD positive feedbacks from water vapour that, miraculously, never turns itself into clouds, triggering negative feedback and buggering the scare up.
That's it, you either believe that, or you don't. If you believe it you are on the side of the Angels if you don't your on the side of the Devil. Just a new wave of religious fervour demanding instant sacrifice for future happiness.
There is empirical evidence that the GHG theory is wrong but there is as yet no empirical evidence to prove any other theory is correct.
Ice cores are empirical evidence, you can hold them in your hands (and get frostbite hehe).
The proxies used to extract temperature and CO2 information are understood and accepted.
Once the warming started in the Holocene interglacial it took between 400 and 800 years before CO2 began to rise, the GHG theory states that this amplifies the warming. However the temperature of our interglacial plateaued and began to fall roughly 10,000 years ago even though CO2 continued to rise and still does rise.
The only two conclusions one can draw from this are:
CO2 has no role in warming the planet
OR
CO2 has a warming effect between certain ppm levels but that at or around 200 ppm the effect stops.
Dung
CO2 has a warming effect between certain ppm levels but that at or around 200 ppm the effect stops.
One of the things I like least about discussion with sceptics is what I call the 'goldfish syndrome'. By which I mean that one makes a perfectly valid, perfectly clear point and somehow it just gets 'forgotten'. Usually with frightening speed.
In this instance, may I take you back to the first page of this discussion and direct your attention to my comment at Jul 23, 2012 at 8:51 PM?
Now may I ask you to *think* about the overall shape of the Zachos curve, while bearing in mind that Svensmark's 'cosmoclimatological' hypothesis does not provide any explanation at all for the bigger picture, at least as far as Cenozoic climate change is generally considered?
Really *think*.
We've all now heard about that duff paper you read. Now, stick to the topic and don't be so condescending.
rhoda
If you think there are errors in the methodology of HS12, you need to point them out. Or you need to retract your claim that the paper is 'duff'.
BBD
A guy named Richard Feynman became a very famous man and scientist and one very basic principle that he advocated has stood the test of time.
It does not matter how clever a scientist is or how impressive his theory is, just one experiment that produces "the wrong result" is enough to decide that the theory is rubbish. The wrong result is one where predicted results do not agree with experimental results.
What I have quoted is a well reported and documented period of time during which CO2 and temperature behave in a way that in no way agrees with the GHG theory. Therefore it is rubbish.
Or you could explain why Svensmark's 0.92 correlation between cosmic rays and cloud cover can be simply ignored.
Or you tell us if you agree that it is correct that CO2 absorbs IR between certain concentrations and at certain wavelengths only and if not on what basis you reject this hypothesis.
Or you could explain why if there is a positive feedback from increased water vapour in the atmosphere the effect is not lessened by the inevitable formation of clouds.
Any reason for not engaging with us on these matters?
BBD
As has been said by others, I do not trust Hansen not least because he appeared before a senate committee and said that exaggerating a problem was a good thing because it helped to focus the public's mind on the need to take action.
I decided to look at Hansen and Sato (2012) so I followed one of your links (to Fig 1).
Bingo!
A graph showing the interglacials in the current ice age, a period I have studied quite a lot ^.^
I have a paper on my hard drive somewhere (pls dont make me find it) which concluded that the maximum temperature reached in our current Holocene interglacial was 6 deg C lower than that in the previous Eemian interglacial. In giving his findings the author mentions that there are other papers released recently that put the difference at 10 deg C.
However lets keep this in an area that you might be happy with, The graphs of the interglacials shown in AR4 put this temp difference at 3 deg C.
Hansen and Sato conclude that the difference is just 0.5 deg C. The phrase "touch with a ten foot barge pole" comes to mind.
I will read further about the bits you wanted me to look at.
matthu
OK I understand your problem now so I will attempt to justify talking about it here.
There is as far as I know, no dispute over the fact that increased sunspot activity (increased solar magnetic field/solar wind strength) is related to reduced intensity of cosmic rays entering the Earth's atmosphere. Please comment if you do not accept this.
There is much evidence for several hundred years that sunspot activity is linked to temperature (I will cite papers if you need them) however the reason for this was unknown.
A book by Henrik Svensmark and Nigel Calder called "The Chilling Stars" was published in 2007. In this book Svensmark suggested that the interaction of cosmic rays (sub atomic particles) with molecules in the atmosphere resulted in some large molecules arriving at the Earth's surface and seeding low level clouds. At the end of the book Svensmark added that he had proved this effect in his own small lab but that it would be tested on a larger scale by a team of 50 scientists at CERN.
As far as I know the testing at CERN is still ongoing and so far only an interim report has been released. The interim report confirmed Svensmark's theory but refused to draw conclusions and a further report is long overdue.
Is this enough for you to accept that cosmic rays are a valid issue in this thread? They seem to be better supported than the GHG theory to me ^.^ .