Henrik Svensmark’s hypothesis, it’s the sun

Posted: August 24, 2011 by tchannon in Astrophysics, climate, Politics, Solar physics

This is a quick pointer to news about the CERN CLOUD experiment.

Others have more time to do the topic justice.


Thanks to Tenuc for pointing out the [above] from Nigel Calder’s blog

As some others are saying, don’t go assuming too much just yet.

A good thread on WUWT containing many pointers to elsewhere.

I might add more later.

  1. Tenuc says:

    So, confirmation that the CLOUD experiment failed to falsify Henrik Svensmark’s hypothesis that most of the global warming of the 20th Century can be explained by the reduction in cosmic rays due to stronger solar activity, which resulted in less low cloud cover and a greater influx of insolation. Good news for those of us who are sceptical of the claims that man-made CO2 was to blame… 🙂

    The following is from Nigel Calder’s blog…

    “A graph they’d prefer you not to notice. Tucked away near the end of online supplementary material, and omitted from the printed CLOUD paper in Nature, it clearly shows how cosmic rays promote the formation of clusters of molecules (“particles”) that in the real atmosphere can grow and seed clouds. In an early-morning experimental run at CERN, starting at 03.45, ultraviolet light began making sulphuric acid molecules in the chamber, while a strong electric field cleansed the air of ions. It also tended to remove molecular clusters made in the neutral environment (n) but some of these accumulated at a low rate. As soon as the electric field was switched off at 04.33, natural cosmic rays (gcr) raining down through the roof of the experimental hall in Geneva helped to build clusters at a higher rate. How do we know they were contributing? Because when, at 04.58, CLOUD simulated stronger cosmic rays with a beam of charged pion particles (ch) from the accelerator, the rate of cluster production became faster still. The various colours are for clusters of different diameters (in nanometres) as recorded by various instruments. The largest (black) took longer to grow than the smallest (blue). This is Fig. S2c from supplementary online material for J. Kirkby et al., Nature, 476, 429-433, © Nature 2011”

    Like Climategate, this will be another game changing moment for those scientists and politicians promoting the CAGW scam. The truth will always out!

    [Thanks, added image to the post — co-mod, Tim]

  2. Doug Proctor says:


    From my WWWT comment:

    As I read the abstract, the following points are made:

    1. More than half the cloud droplets come from ion-induced droplets.

    2. Current ammonia levels in the atmosphere increase the nucleation numbers by 100 – 1000 X at occurring in a non-ammonia containing atmosphere.

    3. Current cosmic ray densities increase the amounts of nucleation between 2 and >10 relative to a non-cosmic ray environment as long as there is enough ammonia in the atmosphere. (the rate increases until saturation or stability occurs at the higher rates).

    We “know” average cloud cover is about 26% (?) and cloud albedo between 0.6 and 0.9, averaging for this purpose 0.75 (?). The current insolation, averaged over the globe, is TOA 340.5 W/m2.

    The IPCC give a value of about 3.4 W/m2 for a radiative value of the doubling of CO2, leading to a 1.4C – 3.0+ under current projections (> 2 ppmv/yr CO2) for Y2100.


    1. There is more than enough ammonia in the atmosphere to “use” more cosmic rays.
    2. An increase of cosmic gamma rays by 2% (for example) leads to a 4% – >20% increase in nucleation numbers.
    2. An increase of 4-20% increase in nucleation numbers leads to a 2-10% increase in cloud formation.

    Given what we “know” about current cloud covers and insolation, a 2% increase in cosmic ray input leads to between an increase of 0.52% to 2.6% cloud cover (.265 to .286 cloud cover), and an increased reflectance of a 0.135 W/m2 to 6.64 W/m2 (using an RF of 0.75 for clouds).


    1. The equivalent radiative power for a 2% increase in cosmic ray input, 0.14 – 6.6 W/m2, is within the current range required to account for the global temperature increase since 1820, and beyond that of a worst-case scenario for CO2.

    2. This experiment establishes an “as-good-as” mechanism as anthropogenic CO2 for the observed post-LIA temperature rise, and, in particular, the post-1965 temperature rise IF a rise in cosmic ray input equal to or less than 2% of the pre-LIA and/or pre-1965 period can be established.



    1) Could someone check/redo the math?
    2) Could someone pull up a cosmic ray input graph of density vs time?

    Bottom line – how much cosmic ray increase do we need to replace CO2 as a heating factor?


    Update: someone on WUWT said that there has been no change in cosmic ray input to the Earth’s atmosphere for 50 years. Clearly Svensmark’s work requires more cosmic rays getting in than before. Is it true that there has been no change? It doesn’t require much, a my math (?) seems to show.

  3. Tenuc says:

    Doug, thanks for a good summary that the Svensmark effect is of the right order of magnitude to produce observed climate changes. There is no doubt that solar activity was increased during the latter half of the 20th century and has now started to fall again. The oceans provide a buffer of energy which takes time to work it’s way through the climate system so there will be lags between cause and observed effects.

    I found this bit of the Kirby material interesting…

    “…In an early-morning experimental run at CERN, starting at 03.45, ultraviolet light began making sulphuric acid molecules in the chamber, while a strong electric field cleansed the air of ions. It also tended to remove molecular clusters made in the neutral environment…”

    Perhaps other effects on cloud nucleation precursors, like varying amounts of ions, could be complicating the linear relationship of the Svensmark effect?

  4. Lord Beaverbrook says:

    Our database includes world-wide cosmic-ray neutron observations (pressure-corrected 1 hour counts) since 1953.
    Takashi Watanabe
    WDC for Cosmic Rays
    Solar-Terrestrial Environment Laboratory, Nagoya University
    Nagoya 464-8601, Japan


    Is this of any use?

  5. tchannon says:

    There is data. Probably have a look when I am clear of some other things.

  6. A. C. Osborn says:

    If there had been no measurable change in the Cosmic Rays that Svensmark talks about how could he have come up with a correlation & hypothesis in the first place?

  7. Tenuc says:

    Interesting comment from Henrick, who as usual is modest and quietly confident that his theory is good.

    Svensmark welcomes the new results, claiming that they confirm research carried out by his own group, including a study published earlier this year showing how an electron beam enhanced production of clusters inside a cloud chamber. He acknowledges that the link between cosmic rays and cloud formation will not be proved until aerosols that are large enough to act as condensation surfaces are studied in the lab, but believes that his group has already found strong evidence for the link in the form of significant negative correlations between cloud cover and solar storms (which reduce atmospheric ionization). “Of course, there are many things to explore,” he says, “but I think that the cosmic-ray/cloud-seeding hypothesis is converging with reality.”

  8. Roy Martin says:

    Tenuc’s starting reference made a good point. It crossed my mind shortly after I started reading the WUWT blog comments that there might be a sort of ”Kirkby Code” in the paper. Easy enough to comply with political correctness in the Abstract, but if there was real evidence he could very well include it with some oblique references or comments, there for the finding.

    The full paper will make interesting reading.

  9. Ulric Lyons says:

    If GCR`s were directly forcing cloud cover, we would expect to see changes in clouds that correspond to the roller-coaster ride of the GCR levels, but we do not…

  10. tallbloke says:

    Edit by Tim:
    Mostly text by Shaviv is here for anyone with visual problems

  11. suricat says:


    I must be thick because I don’t understand how sulphuric acid can be generated in that ‘sterile’ environment.

    OK! I’m happy with ammonia and nitric acid being generated from a sterile atmosphere by way of N2 dissociation, but ‘sulphur derivatives’ (?). I can only think that there must’ve been unexpected contamination within the chamber, or unobserved GCR invasion has included sulphurous protons.

    Any ideas?

    Best regards, Ray.

  12. tchannon says:

    “Sulphur dioxide was added to the chamber only in the final days of the run.”

    “Results from the CERN pilot CLOUD experiment” –2010

    Click to access acp-10-1635-2010.pdf

    And Nature 2011, supplementary info should do the trick

    Click to access nature10343-s1.pdf

  13. Steven Mosher says:

    So gents.. data is waiting for hypothesis testing

  14. tallbloke says:

    I’ll see if we can get Henrik or Jasper over for a chat. 8)

  15. Steven Mosher says:

    Here’s a bet: If i take an average of the insolation from 2/11-2/18 and we have
    and event on 2/19.. whats your prediction for insolation the week after the event?

  16. tallbloke says:

    Rainy in the mountains with sunny intervals on the east coast . Dark at night.

    C’mon Mosh, what sort of ‘event’?

  17. Steven Mosher says:


  18. tchannon says:

    Might be some “interesting” modulation effects from the diurnal sampling.

    Has anyone done detailed work on CR events? What I have in mind here is a spatial effect from various causes including for the US the effect of geomagnetism. If an event has a spatial shape which matches theory that would be rather nice.

    I think the effect is real and what we need is a post mortem of a good event. In a way this is a particularly malleable event which is in effect a natural experiment.

  19. tchannon says:

    There ought to be something in Chilbolton data, worlds largest steerable meteorological radar which is near here… except we don’t know how it manifests. Or maybe it doesn’t.


    Graphical plots can be access from the University of Reading, part of cloudnet

    Level 1 observational data

    if I have this correct an event happened 30th October 2003

    November 2003 from Chilbolton

    Google map of radio dish

    Science and Technology Facilities Council (STFC), Chilbolton Facility for Atmospheric and Radio Research, [Wrench, C.L.]. Chilbolton Facility for Atmospheric and Radio Research (CFARR) data, [Internet]. NCAS British Atmospheric Data Centre, 2003-,Date of citation. Available from http://badc.nerc.ac.uk/view/badc.nerc.ac.uk__ATOM__dataent_chobs.