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Earths albedo controlled by cosmic rays

  1. Jan 16, 2008 #1
    The Danish scientist Henrik Svensmark has been scorn for several years now because of his alternative explanation of how earths temperature varies. His theory states this:

    High solar activity is a sign of a strong magnetic field from the sun
    Strong magnetic field from the sun will decrease the amount of cosmic rays/particles which enters earths atmosphere
    As these particles are "grains" for condensation of low clouds, a reduction of the incoming particles will result in less low altitude cloud formation (Low clouds are an important factor in reflecting suns incoming energy to earth, that is, increasing earths albedo.)
    Earths temperature rise

    This was the short explanation. The complete text is called "Cosmoclimatology: a new theory emerges" [A&G February 2007 - Vol.48].

    At the moment it seems like the IPCC has managed to quiet down any alternative explanations to CO2 driven Global Warming.

    There must be a people scattered throughout the world who are members on this forum, a lot of them also attending universities/colleges. So what I was wondering about is:
    Is there a general acceptance for CO2 as the cause for GW?
    Are Henrik Svensmarks theories well known?
    Last edited: Jan 16, 2008
  2. jcsd
  3. Jan 16, 2008 #2


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    Cosmic rays don't seed low clouds, they can be seeded by smoke and pollution particles but not by muons - I call quackery!

    There is pretty much acceptance that greenhouse gases (CO2 is the most common but not necessarily the greatest overall effect) cause global warming.
  4. Jan 16, 2008 #3
    Hmm.. Have you even read any of svensmarks papers?

    The cosmic rays referred to are mainly protons (90%) and alfa particles (9%), in energy ranges from 0.01GeV and 15GeV. The theory is based on these rays ionizing and "catalyzing" the formation of condensation cores {"Variation of cosmic ray flux and global cloud formation - a missing link in solar-climate relationship" [Henrik Svensmark and Egil Friis-Christensen "Journal of Atmospheric and Solar-Terrestrial Physics Vol.59, 1997]}.

    What are your countrary sources? And, did you even read my questions?
  5. Jan 16, 2008 #4


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    I'm sorry that was rude.

    A post by a PF member with a low post count
    Suggesting that GW doesn't happen
    Mentioning a scientist no-one had heard about
    With a newly coined term for a new theory
    With only a partial reference to a paper ( what is A&G ?)
    Alleging a conspiracy by a goverment/internal body to cover it up

    Tends to trip the crank detector !
  6. Jan 16, 2008 #5
    Apology accepted!

    I have not, neither has Henrik Svensmark, stated that there is no global warming. The clue is: "what is the source of the global warming" or "what controls the temperature on earth."

    I have not alleged there is a conspiracy, people tend to do non-logical things without any conspiracy involved.

    I would appreciate that people read "cosmoclimatology: a new theory emerges" first:

    The theory is not new, it was speculated there was a connection in the late in 1980ties. The first papers materializing the theory were published in the late 1990ties.
    Last edited by a moderator: Apr 23, 2017
  7. Jan 16, 2008 #6
    Oh, I forgot. A&G: Astronomy and Geophysics
  8. Mar 15, 2008 #7
    ...What particles? Aren't cosmic rays almost entirely electromagnetic energy, which doesn't seed clouds? Have I missed something from astrophysics?
  9. Mar 15, 2008 #8


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    No cosmic rays are mostly muons or the decay products of more energetic particles.
    Particles can seed clouds (as in a cloud chamber) how much effect they have on an entire planets atmosphere is debatable.
  10. Mar 19, 2008 #9


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    Earth in physicsforums has a lot of this type of stuff. Svensmark has been discussed in many threads here.

    Cosmic rays are energetic particles flying around in space
  11. May 1, 2008 #10
    for those that haven't seen it. It's in 6 parts. Was a TV documentary. I find it very disappointing it took him 16 months to get his work published. It's all politics. CERN has an experiment upcoming.

    You will have to copy and paste as I can't post url's.






  12. May 1, 2008 #11


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    When you browse through the threads here on the earth forum, you will see a rather balanced approach, and different people have different stances on it. It is not the "anti-AGW bashing" that you might expect. I think people are somewhat divided on the subject (as any good frontier research must be !)

    That said, we tend to ban everything which is conspiracy theory - but that doesn't preclude the knowledge that no-AGW proponents have right now more difficulties getting heard than pro-AGW proponents which are on the "politically-correct" wave. That said, it is not because they have a harder time getting published that that automatically means that they must be right :smile:

    My personal view is that the IPCC "is on something" but oversells it. You cannot deny all of the science work that goes in it, but I think the scientific issues are still far from "settled and certain so that anyone doubting it is a crank", but it is nevertheless suggestive.

    Other people here have other opinions. You'll find a whole spectrum.
    Last edited: May 1, 2008
  13. May 1, 2008 #12
    Last edited: May 1, 2008
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