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Cosmic Radiation Makes Trees Grow Faster

Posted by kdawson on from the ents-are-going-to-war dept.

Diamonddavej writes "The BBC reports that researchers at the University of Edinburgh have found that Galactic Cosmic Rays (GCRs) somehow makes trees grow faster. GCRs vary according to the 11-year solar cycle, with more GCRs hitting the Earth during solar minimum when there is a lull in the solar wind, which normally acts to protect the inner solar system from external galactic radiation. The mechanism might have something to do with GCRs increasing cloud cover, which diffuses sunlight and increases the efficiency of photosynthesis. Nevertheless, the researchers remain mystified and are requesting further ideas and research collaboration to test hypotheses. (How about Radiation Hormesis, AKA 'Vitamin-R?')" Here is the paper's abstract at the journal New Phytologist. The researchers say: "The relation of the rings to the solar cycle was much stronger than to any climatological factors. ... As for the mechanism, we are puzzled."

32 of 162 comments (clear)

  1. Big Surprise by JumperCable · · Score: 4, Funny

    researchers at the University of Edinburgh have found that Galactic Cosmic Rays (GCRs) somehow makes trees grow faster

    I don't think they need to look any further for answers than the Fantastic Four.

  2. It's called research by EdIII · · Score: 4, Funny

    As for the mechanism, we are puzzled

    Geez and they're scientists? Just do a little research. I suggest Marvel Comics. Plenty of good info there. At the risk of starting war, I would caution them against research using DC Comics as they are for simple idiots that live in their mother's basements.

    1. Re:It's called research by jdgeorge · · Score: 2, Funny

      mothers'

      No, the GP was implying that people who read DC Comics are all children of the same mother, and that they live in a multitude of basements that she owns. That mother must be one amazing woman.

  3. causality is possibly wrong by wizardforce · · Score: 5, Interesting

    If the solar cycle is what determines the level of GCR that gets to Earth then it may very well have absolutely nothing to do with the tree growth its self but an indicator of solar conditions which influence tree growth rates.

    --
    Sigs are too short to say anything truly profound so read the above post instead.
    1. Re:causality is possibly wrong by socsoc · · Score: 2, Funny

      But correlation is causation.

    2. Re:causality is possibly wrong by cjfs · · Score: 3, Funny

      But correlation is causation.

      No, the two are merely correlated.

      Ow...

    3. Re:causality is possibly wrong by khayman80 · · Score: 3, Interesting

      That's what I'm thinking too. GCR intensity is highest when sunspot activity is lowest, generally modulating on an 11 year cycle. But solar irradiance also varies at the same frequency; the Sun is actually (~0.1%) brighter when more sunspots are present, contrary to intuition.

      If tree growth between 1953-2006 really is highest when sunspot activity is lowest, that implies trees grow faster when the Sun is very slightly dimmer. Weird. Their diffusion explanation makes sense, but as they note this cloud condensation effect is supposed to be a very small effect. Perhaps it's just large enough to be noticed in these proxy data, though. I agree, however, that a link to solar irradiance is more intuitively appealing, and it's not immediately obvious how it could be ruled out.

      I'd bet they've already considered this issue and ruled it out, possibly by using satellite measurements of solar irradiance and solar wind over the last few decades. They're supposed to be tightly correlated, but if the solar wind varies even slightly differently than solar irradiance it should be possible to see which is causing this variation in growth rates.

    4. Re:causality is possibly wrong by Eukariote · · Score: 2, Informative

      Though there is little variation at visible and near UV wavelengths, the solar flux has a huge (factor of three) variation with the solar cycle in the extreme UV: http://www.usc.edu/dept/space_science/sem_data/SEM%20Data%20Graphs/SEM_1996-2009.jpg.

      EUV and X-ray photons constitute a marked fraction of the total solar output. A much larger fraction than you would expect from the short-wavelength tail of the black-body spectrum of the solar surface. Indeed, these emissions are mostly from the corona, not the surface: EUV at 171A http://www.lmsal.com/YPOP/ProjectionRoom/latest_TRACE_171.html, and an X-ray image http://www.lmsal.com/YPOP/ProjectionRoom/latest/sxt/full/sxtdag_512.gif.

      Such high-frequency photons are absorbed in the very upper layers of the atmosphere. However, roughly 50% of the secondary energetic effects (heating, fluorescence, ionization-recombination emission, etc.) will reach ground level instead of going back out into space.

      If something here on earth is varying with the solar cycle, the first cause to consider is therefore the solar EUV and X-ray flux.

  4. cue the bad superhero jokes ... by Korbeau · · Score: 4, Funny

    in one, two, tree ...

    1. Re:cue the bad superhero jokes ... by L4t3r4lu5 · · Score: 2, Funny

      Less of that! Now, please leaf.

      --
      Finally had enough. Come see us over at https://soylentnews.org/
  5. Cloud cover by MichaelSmith · · Score: 4, Interesting

    The mechanism might have something to do with GCRs increasing cloud cover, which diffuses sunlight and increases the efficiency of photosynthesis.

    How about cloud cover leads to more precipitation?

    --
    http://michaelsmith.id.au
    1. Re:Cloud cover by pclminion · · Score: 2, Insightful

      How about cloud cover leads to more precipitation?

      No. Precipitation cannot be larger than evaporation. Evaporation is heat driven, and cosmic rays do not input enough heat energy to significantly contribute to evaporation.

    2. Re:Cloud cover by MichaelSmith · · Score: 3, Insightful

      How about cloud cover leads to more precipitation?

      No. Precipitation cannot be larger than evaporation. Evaporation is heat driven, and cosmic rays do not input enough heat energy to significantly contribute to evaporation.

      Radiation nucleates droplets in clouds so that water vapor precipitates where it otherwise would have stayed in the atmosphere. Its a bit like how dust from outer space contributes to rainfall by encouraging the formation of drops big enough to fall as rain.

      --
      http://michaelsmith.id.au
    3. Re:Cloud cover by MichaelSmith · · Score: 2, Interesting

      Yeah well it depends on where you are. Here in Australia getting water vapor to precipitate before it crosses the east coast is an issue. Most of it flies right over because we don't have enough terrain to push it up to form ice.

      --
      http://michaelsmith.id.au
    4. Re:Cloud cover by radtea · · Score: 2, Interesting

      just having a hard time visualising that sometime in our evolutionary history there were some animals that didn't age.

      They're called micro-organisms, although they don't exactly "not age". They reproduce by binary fission and therefore the offspring cells are nominally genetically identical to the parent. You can, if you like, say that one of them IS "the parent" (possibly with a bit of genetic modification) and the other is "the offspring." If you look at it that way (which admittedly takes a bit of squinting) their are single-celled organisms that around that are millions of years old (but genetically very different from their nominally identical selves of millions of years ago, due to those accumulated modifications.)

      The GP's point is also not exactly correct: "competition" in the evolutionary sense doesn't happen between species. It happens between individuals of the same species. So a better way of putting the argument is: species with very long lifespans will be strongly selected for shorter lifespans when the rate of environmental change is high.

      That is, the individuals who reproduce younger will have a larger chance of having offspring that are well-suited for the current environment, and those offspring will tend to reproduce younger as well, allowing the next generation's selective filtering (a nice euphemism for killing lots and lots of individuals) to operate rather more gently than on the offspring of individuals that reproduce later in life.

      Age of first reproduction tends to be strongly anti-correlated with longevity. It's just like writing code under a tight deadline: the adaptations to get the job done fast tend to reduce maintainability, and it appears that the advantage of reaching the age of reproduction earlier and having a shorter reproductive lifespan is, in the typical environments found on Earth, more significant than building to last but not squeezing out those first pups for a couple of years after your contemporaries have.

      If the Earth's environment were far more stable, species would be much longer lived. As it is, with significant natural climate variation on all timescales from decadal to milenial, a very long-lived species would have individuals adapted to one environment pushing out offspring in environments that they would be relatively ill-adapted for. There's very little selective advantage in that (although one could perhaps argue for the advantage of a really, really long-lived species that was able to wait it out until the next round of optimium conditions occurred. But there are some minima that even evolutionary algorithms have a hard time reaching.)

      --
      Blasphemy is a human right. Blasphemophobia kills.
  6. Repeat after me: Correlation Is Not Causation by Shaterri · · Score: 4, Insightful

    Especially in a case like this, where there are other tightly-correlated variables. Why is the authors' presumption that it's the cosmic rays (or lack thereof) that are regulating tree growth, rather than solar and sunspot activity itself? It seems at least as plausible to me that sunspot activity correlates to some other solar features (e.g., solar irradiance) that would have a more natural and direct effect on tree growth than cosmic rays.

    1. Re:Repeat after me: Correlation Is Not Causation by MichaelSmith · · Score: 3, Informative

      Are you saying that tree growth may be causing cosmic radiation?

      --
      http://michaelsmith.id.au
    2. Re:Repeat after me: Correlation Is Not Causation by Anonymous Coward · · Score: 3, Funny

      it's the butterfly effect or something

  7. It's Simple Really by eldavojohn · · Score: 5, Funny

    What else grows from radiation? Cancer. Quod erat demonstratum, trees are cancer. Therefore we must cut them down and burn them. Perhaps form some sort of industry devoted to this.

    What? The "logging" industry? Oh, well, very good then. Continue.

    --
    My work here is dung.
    1. Re:It's Simple Really by MichaelSmith · · Score: 4, Funny

      I am the lorax. I speak for the trees, which you seem to be cutting as much as you please.

      --
      http://michaelsmith.id.au
    2. Re:It's Simple Really by maglor_83 · · Score: 2, Funny

      Yes.

  8. Re:Breaking News by olsmeister · · Score: 4, Informative

    Chernobyl is not cosmic radiation.

  9. Re:Once upon a time by wizardforce · · Score: 3, Informative

    objects do not become radioactive unless they are bombarded with neutron radiation, high energy protons or extremely high energy gamma radiation capable of ejecting a proton or neutron to form a radioactive isotope. Simply irradiating an object does not necessarily make the object radioactive. Now in so far as plants having a higher growth rate due to radiation, I haven't heard much on the subject other than radiotropic melanized fungi living near Chernobyl having a substantially increased growth rate.

    --
    Sigs are too short to say anything truly profound so read the above post instead.
  10. Life imitates Gilligan's Island by bigsexyjoe · · Score: 2, Funny

    The cool thing is that you get super powers from eating the giant vegetables, too.

    --
    Democracy Now! - your daily, uncensored, corporate-free
  11. Paul Zindel by sohp · · Score: 2, Funny

    A 1964 publication by Paul Zindel entitled "The Effect of Gamma Rays on Man-in-the-Moon Marigolds" predates this research by quite a bit.

  12. Nitrogen Fixation by physburn · · Score: 5, Insightful
    This is an easy mystery to solve. When a cosmic ray hits the atmosphere, it creates a shower of ionizing radiation, each of the secondary particles are enough to ionizing oxygen and nitrogen molecules in the atmosphere, forming nitrogen oxides, these react ready with water forming nitric acid, which will precipitate in dilute form in the rain. Only lightning and cosmic rays can form nitrogen oxide, and lightning is relatively rare, so the amount of available free nitrates in the soil, depends very much on the amount cosmic rays hitting the earth.

    Plants of course need nitrogen to grow, the trouble is they can't absorb nitrogen from the atmosphere (except for Legumes (pea, and beans and similar plants)). So for the majority of plants and trees, not feed by human fertilizers, the amount of fertilizing nitrate available to them, is directly proportional the cosmic ray flux.

    Mystery Solved.

    ---

    Dark Matter Feed @ Feed Distiller

    1. Re:Nitrogen Fixation by AJWM · · Score: 3, Interesting

      Only lightning and cosmic rays can form nitrogen oxide, and lightning is relatively rare,

      Well no, lighting is fairly common, actually -- there's always a lighting storm going on somewhere. However, if one assumes that the global rate of lightning is fairly constant then given that the amount nitrogen oxides contributed by cosmic rays fluctuates, you'd still see a correlation. So you may be right.

      --
      -- Alastair
  13. The Simpsons Had It Right. by Ironlenny · · Score: 2, Funny

    Homer: If we learned one thing from "The Amazing Colossal Man" and "Grasshopperus," it's that radiation makes stuff grow real big, real fast.

    --
    There is a system for subverting the system and you should use that system!
  14. Further ideas? by kauttapiste · · Score: 5, Funny

    Nevertheless, the researchers remain mystified and are requesting further ideas ...

    Have they considered Ask Slashdot?

  15. Re:I remember this finding... by tabrnaker · · Score: 3, Insightful

    Obviously you've never grown plants!
    Get back to us when you have real knowledge and not 'book smarts'.

  16. Complex Systems + Causality ... by foobsr · · Score: 2, Interesting

    Quote:"One of the reasons people have difficulty in dealing with complex systems is that the linear causal chain way of thinking - A causes B causes C causes D ... etc - breaks down in the presence of feedback and multiple interactions between causal and influence pathways. One could say that complex systems are characterised by networked rather than linear causal relationships."

    Keeping that in mind, I tend to be of the opinion that the best guess regarding an isolated cause is '42'.

    CC.

    --
    TaijiQuan (Huang, 5 loosenings)
  17. Sun spots by Anonymous Coward · · Score: 3, Interesting

    At the university I studied physics at, they had a nice (old) telescope with which they projected solar images to count sun spots. They had a graph on the wall of the number of sun spots, going decades back. There was a nice periodicity in that graphc, and interesting thing is that they could point out two types of events: good wine years, and the occurrence of the "Elfstedentocht" (a major Dutch ice skating event which only happens when the outdoor ice conditions are exactly right).

    I forgot which one happened at sunspot maxima and which at the minima, but there was a striking correlation.