John Grace: relationship between galactic cosmic radiation and tree rings

Posted: December 8, 2011 by tallbloke in climate, cosmic rays, Geomagnetism, Solar physics, solar system dynamics
Well, this should spark a bit of renewed interest in paleodendrotealeafology :-)
date: Thu, 01 Oct 2009 13:00:47 +0100
from: Keith Briffa <>
subject: Fwd: paper indicating a link between tree growth and global cosmic
to: t.m.melvin

>Date: Wed, 30 Sep 2009 16:14:57 +0100
>From: John Grace
>To: Luyssaert Sebastiaan
>         "Smith, Professor Pete" ,

>         Sandy Tudhope
>         Schulze Ernst-Detlef ,
>         "Sellers, Piers J. (JSC-CB)"
>         Sha Liqing  SIEGERT Martin
>         Steve Long  Tarja Lehto
>         Thomas Crowley Tim Hill
 [around 120 names and email addresses removed from here]
>         Torben Christensen
>         "Veenendaal, Elmar"
>         Werner Eugster
>         Yadvinder Malhi
>         Yit Arn Teh  Jon Lloyd
>         Jennifer Pannell
>         Achim Grelle
>         Otmar Urban
>Subject: paper indicating a link between tree
>growth and global cosmic radiation

>Dear Colleagues
>We have found a correlation between tree rings and galactic cosmic radiation:
>This is an unexpected result, for which we don't
>yet have a good explanation. I hope doesn't
>result in scientific excommunication!
>I thought it would be good idea to circulate
>this reference to relevant scientific friends- so here it is.
>We have one other data set for a different
>species, but spanning many more years. We'll be investigating this case.
>Best wishes
>John Grace
>Professor John Grace
>Professor of Environmental Biology
>School of GeoSciences
>Crew Building
>University of Edinburgh

Professor Keith Briffa,
Climatic Research Unit
University of East Anglia

A relationship between galactic cosmic radiation and tree rings

  1. Sigrid Dengel,
  2. Dominik Aeby,
  3. John Grace

Article first published online: 14 SEP 2009

DOI: 10.1111/j.1469-8137.2009.03026.x


  •  Here, we investigated the interannual variation in the growth rings formed by Sitka spruce (Picea sitchensis) trees in northern Britain (55°N, 3°W) over the period 1961–2005 in an attempt to disentangle the influence of atmospheric variables acting at different times of year.
  •  Annual growth rings, measured along the north radius of freshly cut (frozen) tree discs and climatological data recorded at an adjacent site were used in the study. Correlations were based on Pearson product–moment correlation coefficients between the annual growth anomaly and these climatic and atmospheric factors.
  •  Rather weak correlations between these variables and growth were found. However, there was a consistent and statistically significant relationship between growth of the trees and the flux density of galactic cosmic radiation. Moreover, there was an underlying periodicity in growth, with four minima since 1961, resembling the period cycle of galactic cosmic radiation.
  •  We discuss the hypotheses that might explain this correlation: the tendency of galactic cosmic radiation to produce cloud condensation nuclei, which in turn increases the diffuse component of solar radiation, and thus increases the photosynthesis of the forest canopy.
[UPDATE] The full article is available here - well spotted PG.
  1. tallbloke says:

    Briffa responds to an earlier email from John Grace before John drops the bomb with the news of publication above, which is cc’d to the entire climate community:

    date: Thu Sep 25 09:53:04 2008
    from: Keith Briffa
    subject: Re: EU 2009 call and tree rings
    to: John Grace

    sorry about missing question – yes many tree-ring people in the past have “seen” various
    cycles in tree-ring records and often attributed them to solar forcing . Virtually all of
    the work lacks rigour in terms of proper testing of he phase of associations or realistic
    tests of the significance. A decade or so back there was a virtual industry in Russia –
    driven largely by the political need for palaeo work to demonstrate prognostic value. I am
    posting a brief review article I wrote some years ago that has a few relevant references.
    There have been one or two papers since from Russian workers, but again not convincing to
    my mind.

  2. adolfogiurfa says:

    Briffa`s Lonely Tree:

    I’m a lonely tree, standing in a corner still
    Waiting for the summer day
    But I can feel the rain
    But who cares, if I cry, a thousand cries
    Nobody would even try to talk to me

    Para, papara ra… papararara, papaparara
    I hope someday, that my life
    Will be okey. Even if for just one day
    For just one day!


  3. tchannon says:

    A factor which I have not seem discussed is the matter of starvation, trees in general being required to grow without human external input, sometimes on land farmed for trees, tends I suggest to reduce growth.

    There is also the dire effect of unintended side effects from past environmental law change, which has actually pushed UK farming into trouble and raised costs, such as the reduction in airborne sulphur. This is very well proven (a post I might make sometime would show this) but that is for agricultural food crops, forestry and heaven forbid anything natural is an unknown.

    I seem to recall some kind of connection between nitrogen fixation and solar, what with that and mist, fog, rain there are many possibilities. This might even explain hide the decline…

    Auxiliary nitrogen fixation is affected by cloud

    Click to access Effects%20of%20Solar%20Radiation%20on%20Grain%20Legumes,%20Eriksen,%20Whitney,%201984.pdf

    N. fixation also comes from lightning and combustion, the former perhaps with a solar connection and the latter being enviro controlled.

    I think this says that long ago it would all have been natural well away from humans but once humans enter the scene things get pretty complex.

    Finally for amusement let me turn this back onto Edinburgh University

  4. Gerry says:


    “Correlations were based on Pearson product-moment correlation coefficients
    between the annual growth anomaly and these climatic and atmospheric factors.

    Rather weak correlations between these variables and growth were found. However, there was a consistent and statistically significant relationship between growth of the trees and the flux density of galactic cosmic radiation. Moreover, there was an underlying periodicity in growth, with four minima since 1961, resembling the period cycle of galactic cosmic radiation.

    We discuss the hypotheses that might explain this correlation: the tendency of galactic cosmic radiation to produce cloud condensation nuclei, which in turn increases the diffuse component of solar radiation, and thus increases the photosynthesis of the forest canopy.”

    In the email sent by Grace to his colleagues, we read
    “Dear Colleagues
    We have found a correlation between tree rings and galactic cosmic radiation:

    “This is an unexpected result, for which we don’t yet have a good explanation. I hope doesn’t result in scientific excommunication!”

    The email is priceless because Grace was so afraid of being excommunicated by his AGW colleagues that he didn’t mention Svensmark’s name in the article, and also did not mention the known link between the galactic cosmic ray flux cycle and the solar cycle. The cosmic ray maximum flux times shown in Figure 3 of the article all occur at times of minimum solar sunspot activity (1965, 1977, 1987, and 1997).

    His fear of being excommunicated proved to be well founded, as he was apparently shunned by the AGW gang after publication of the article, in which he had revealed himself to be a traitor to the AGW Cause by including this reference:

    Svensmark H, Friis-Christensen E. 1997. Variation of cosmic ray flux
    and global cloud coverage – a missing link in solar-climate relationships.
    Journal of Atmospheric and Solar-Terrestrial Physics 59: 1225-

  5. tallbloke says:

    BBC article

    “The intensity of cosmic rays also correlates better with the changes in tree growth than any other climatological factor, such as varying levels of temperature or precipitation over the years.
    “The correlation between growth and cosmic rays was moderately high, but the correlation with the climatological variables was barely visible,” Ms Dengel told the BBC.
    Here comes the Sun
    Cosmic rays are actually energetic particles, mainly protons, as well as electrons and the nuclei of helium atoms, that stream through space before hitting the Earth’s atmosphere.
    The levels of cosmic rays reaching the Earth go up and down according to the activity of the Sun, which follows an 11-year cycle.”

    “Ms Dengel’s team proposes two main hypotheses as to how cosmic ray particles could influence the growth of trees.
    The first idea is that cosmic rays ionise gases in the atmosphere, creating molecules around which clouds condense, therefore increasing cloud over.
    This mechanism is hotly debated among scientists, and evidence for it is weak.
    One study published in 2006 suggested it may account for as little as 2% of the variation in cloud cover across the UK.
    But if it does occur, then an increase in cloud cover and haze would diffuse the amount of solar radiation reaching the trees.
    As diffuse radiation penetrates forest canopies better than direct light, it would increase the amount of radiation that plants capture, and increase photosynthesis by trees, boosting growth.
    Explaining the unexplained
    “Or there is some direct effect,” says Ms Dengel.
    What that might be is unknown, but experiments in space have shown that cosmic rays can have some positive impacts on biological materials.
    Ms Dengel says that much more work needs to be done to investigate the effect further, and their results have received a mixed reaction from other scientists.
    “We sent the paper to 161 international colleagues. We are still harvesting the emails. We’ve identified four groups who would like to work with us on this.
    “Locally, one of our colleagues is a cloud physicist. He was encouraging but sceptical at the same time.”
    If further research backs up the team’s findings, the implications could be significant.
    “We want to repeat this work for larger data sets, and understand the mechanism better, before we speculate,” says Ms Dengel.
    But the influence of cosmic rays could resolve other as yet unexplained cycles in tree growth found in studies in North America.
    It also suggests the amount of aerosols that humans emit into the atmosphere could impact tree growth, as high levels of aerosols cause “global dimming”, an effect that occurs when the levels of light reaching the Earth’s surface fall.”

  6. P.G. Sharrow says:

    “A consistent and statistically significant relationship between growth of the trees and the flux density of galactic cosmic radiation”

    Damn! how to explain that one!. Trees, at least Sitka Spruce, are positive growth effected by Cosmic Rays. I don’t know, perhaps Sitka Spruce are alien invaders from outer space? Everything else is less positive correlated, Temperature, precipitation, crowding, fertilizer, even bear farts 😎 at least they did a good of control and explanation of the source of their data. pg

  7. tallbloke says:

    ChrisM says:
    October 19, 2009 at 6:35 pm (Edit)
    A possible explanation for the extra growth during high comic rays is that if Svensmark is right you would get more cloud cover which would mean warmer nights, most plants do most of their growing at night.
    I have measured Hop plants growing up to a foot in one night when it was warm and thundery.

  8. P.G. Sharrow says:

    Tallbloke is correct, it is the sunlight! who would have thought. The most important input for plant growth is SUN LIGHT. This last growing year was a poor year for plant growth. The sun light was weak. Hard for sun lovers like squash and tomatoes. I wonder what the Sitkas would say. pg

  9. tallbloke says:

    PG: Different growing conditions: The article says more radiation gets through the canopy into the trees when cloudier diffuse light conditions prevail. Toms and squashes are full sun lovers.

    There again:

    Keith Minto says:
    October 19, 2009 at 6:57 pm
    The argument used that diffuse sunlight reaches more leaves and produces more growth seems tenuous and not at all robust. Might the diffuse sunlight be from clouds that produce rain and, as mentioned before, warmer nights ?

  10. tallbloke says:

    From a glossy 2007 Edinburgh Uni Global Change pamphlet:

    Sigrid Dengel is working in Sitka spruce forests in North England
    and Central Scotland. The project involves measuring the amount
    of radiation penetrating through
    the trees compared to how much
    is absorbed by the canopy.
    By studying how different cloud
    conditions can affect carbon
    uptake we can understand how
    forests might respond to changes
    in cloud-cover. Such feedback
    mechanisms and linkages are
    important to quantify and predict
    the impact of climate change on
    rates of forest growth in the future.

  11. tallbloke says:

    Sigrid Dengel has one new publication since:
    Methane emissions from sheep pasture, measured with an open-path eddy covariance system
    Sigrid Dengel1,*, Peter E. Levy2, John Grace1, Stephanie K. Jones2,3, Ute M. Skiba2
    Article first published online: 1 JUL 2011

    DOI: 10.1111/j.1365-2486.2011.02466.x

    agriculture;carbon sink;closed path;CO2 flux;global warming potential;grassland;grazing;grazing system;LI-7200;LI-7700
    Methane (CH4) is an important greenhouse gas, contributing 0.4–0.5 W m−2 to global warming….


    Looks like she got busted down to counting sheep farts.
    A waste of a bright postgrad student’s time.
    The price of challenging the Hegerl Hegemony?

    Looks like the cosmic connection to plants was too much of a hot potato…

  12. tallbloke says:

    Philip_B says:
    October 19, 2009 at 7:23 pm
    The increased plant growth from diffuse sunlight is well accepted and uncontroversial. FYI is a link to a text on growing grapes that refers to the effect. Google will give you many more.

    The study found that tree growth changes from changes in temperature and precipitation were so small as to be almost non-existent.

    Which means the GCR effect is NOT through temperature or precipitation changes.

  13. tallbloke says:

    Global change at Edinburgh is Gabi Hegerl’s patch. Her husband Tom Crowley is there too, and is one of the original co2 warmers. Gabi is a big cheese for the IPCC.

    I sense another scandal brewing here over the burying of a cosmic ray climate signal in tree growth which is stronger than temperature or precipitation.

    “Stargate” anyone? 🙂

  14. tallbloke says:

    From the paper:

    “Dendrochronogists have sometimes reported cyclic phenomena in long time-series of tree-rings but they have rarely offered an explanation (Douglass, 1927; Siren & Hari, 1971; Briffa, 1994; Rigozo et al., 2007). For example, in a study of 305 tree-ring chronologies from North America, periods of 18.6 yr and 10.5 yr were found in 286 and 244 instances (Currie, 1991), respectively. These observations have been largely ignored, perhaps because no underlying mechanism could be found to explain the intriguing results.”

    Maybe we can help out on this one. 🙂

    18.6 years – Lunar declination cycle

    10.4 years Jupiter- Earth – Venus alignment Cycle. Also a common solar cycle length over the period GCR’s have been measured since the start of the space age.

  15. tallbloke says:

    Gu, L., D. Baldocchi, S. B. Verma, T. A. Black, T. Vesala, E. M. Falge, and P. R. Dowty (2002), Advantages of diffuse radiation for terrestrial ecosystem productivity, J. Geophys. Res., 107(D6), 4050, doi:10.1029/2001JD001242.

    Clouds and aerosols alter the proportion of diffuse radiation in global solar radiation reaching the Earth’s surface. It is known that diffuse and direct beam radiation differ in the way they transfer through plant canopies and affect the summation of nonlinear processes like photosynthesis differently than what would occur at the leaf scale. We compared the relative efficiencies of canopy photosynthesis to diffuse and direct photosynthetically active radiation (PAR) for a Scots pine forest, an aspen forest, a mixed deciduous forest, a tallgrass prairie and a winter wheat crop. The comparison was based on the seasonal patterns of the parameters that define the canopy photosynthetic responses to diffuse PAR and those that define the responses to direct PAR. These parameters were inferred from half-hourly tower CO2 flux measurements. We found that: (1) diffuse radiation results in higher light use efficiencies by plant canopies; (2) diffuse radiation has much less tendency to cause canopy photosynthetic saturation; (3) the advantages of diffuse radiation over direct radiation increase with radiation level; (4) temperature as well as vapor pressure deficit can cause different responses in diffuse and direct canopy photosynthesis, indicating that their impacts on terrestrial ecosystem carbon assimilation may depend on radiation regimes and thus sky conditions. These findings call for different treatments of diffuse and direct radiation in models of global primary production, and studies of the roles of clouds and aerosols in global carbon cycle.

    See also:
    Still, C. J., et al. (2009), Influence of clouds and diffuse radiation on ecosystem-atmosphere CO2 and CO18O exchanges, J. Geophys. Res., 114, G01018, doi:10.1029/2007JG000675.

    This study evaluates the potential impact of clouds on ecosystem CO2 and CO2 isotope fluxes (“isofluxes”) in two contrasting ecosystems (a broadleaf deciduous forest and a C4 grassland) in a region for which cloud cover, meteorological, and isotope data are available for driving the isotope-enabled land surface model (ISOLSM). Our model results indicate a large impact of clouds on ecosystem CO2 fluxes and isofluxes. Despite lower irradiance on partly cloudy and cloudy days, predicted forest canopy photosynthesis was substantially higher than on clear, sunny days, and the highest carbon uptake was achieved on the cloudiest day. This effect was driven by a large increase in light-limited shade leaf photosynthesis following an increase in the diffuse fraction of irradiance. Photosynthetic isofluxes, by contrast, were largest on partly cloudy days, as leaf water isotopic composition was only slightly depleted and photosynthesis was enhanced, as compared to adjacent clear-sky days. On the cloudiest day, the forest exhibited intermediate isofluxes: although photosynthesis was highest on this day, leaf-to-atmosphere isofluxes were reduced from a feedback of transpiration on canopy relative humidity and leaf water. Photosynthesis and isofluxes were both reduced in the C4 grass canopy with increasing cloud cover and diffuse fraction as a result of near-constant light limitation of photosynthesis. These results suggest that some of the unexplained variation in global mean δ 18O of CO2 may be driven by large-scale changes in clouds and aerosols and their impacts on diffuse radiation, photosynthesis, and relative humidity.

  16. tallbloke says:

    Several of us commented on that WUWT article, including PG, me, adolfo. How things get lost in the fast and furious flow of the climate debate.

  17. Brian H says:

    Diffuse sunlight and warm nights. Even more benefits of AGW*! The gift that keeps on giving …

    *Aided and abetted by GCRs, of course.

  18. adolfogiurfa says:

    @ P.G. Sharrow says: You have touched a sensible argument: GCR : How do these affect trees and…(last but not least) we men?. .. Should we build a “faraday cage” or a big magnetic field to avoid aging too fast?…..that would give us time to see your flying machine flying…. 🙂

  19. Gary says:

    Why are the plant physiologists never consulted? All this speculation about what plants are responding to and you never see a reference to work by the experts, let alone any commentary from them.

  20. P.G. Sharrow says:

    The point that GCR promotes cloudiness and warmer nights is the one that I can agree with. 60 years of watching plant growth one thing I can attest to is warm nights make a great deal of difference. In field crops, daily total growth is greatly reduced if night temperatures drop below 50F and root growth is best if soil temperature is around 72F. Plants are living things that try to keep warm by burning carbohydrates at night. Cold results in use of day created carbohydrates and reduced net growth. Many of our warm weather crop plants such as tomatoes, peppers,squash etc. exhaust them selves and die if kept below 50F for an extended period of time. Sitka spruce in the wild prefers cool and damp conditions at the edge of the treeline as in the far north near the ocean. pg

  21. Roger Andrews says:

    It seems to me that the important question here is; exactly what are tree rings a proxy for?

    It’s always been assumed that they’re air temperature proxies – an assumption that many of us question. But what if they’re really solar activity proxies? That would be a game changer indeed. (The Hockey Stick, for example, would show that the recent warming coincides with an enormous increase in solar activity.) 🙂

    But are tree-rings really solar proxies? I did a quick literature search and came up with a number of studies that identify a link between solar cycles and tree ring widths. The following quote from Rigozo et al. (2006) gives an idea of the results of these studies:

    “Regarding solar activity period, a number of studies have shown them in tree ring samples. The Schwabe 11-yr solar cycle has been found in tree rings from Southern Brazil (Rigozo et al., 2002, 2004; Nordemann et al., 2005), Chile (Nordemann et al., 2005; Rigozo et al., 2006a), Australia and Taiwan (Murphy, 1990, 1991) and in fossil trees from Germany (Kurths et al., 1993). The fourth harmonic of Suess cycle (52 yr) has been found by Damon et al. (1998) studying a tree ring D14C time series, for the time interval between 1065 and 1250 AC. This signal (52 yr) was also found in tree ring data from Concordia, Brazil, by Rigozo et al. (2006b) and from Osorno, Chile, by Nordemann et al. (2005). The 80–100 yr Gleissberg solar activity cycles have been found in samples from Russia and Scandinavia (Raspopov et al., 2000), Australia and Taiwan (Murphy, 1990, 1991), Southern Brazil (Rigozo et al., 2004) and Chile (Rigozo et al., 2006a).”

    We can add to this Dengel et al., who establish a direct link between tree growth and cosmic ray flux, and Liu et al., who in the Tibet thread below replicate their tree ring chronology very closely using solar cycles (which, incidentally, are similar to the solar cycles Tim Channon obtained from Lean TSI, and almost identical in the case of the 110-year cycle.)

    On the basis of these results I think we can assume, at least as a working hypothesis, that tree rings are indeed a proxy for solar activity, and a better proxy for solar activity that they are for temperature or precipitation.

  22. Stephen Wilde says:

    The trees would grow better during a period of active sun because the surface pressure distribution shifts poleward to provide more surface warmth over larger areas and more rainfall too as long as the trees don’t shift under drought affected sections of the permanent climate zones.

    Additionally the warmer ocean surfaces absorb less CO2 allowing a build up in the air to aid growth worldwide.

    I see the change in cosmic ray quantities as a side effect of the solar changes with little or no climate effect.

    It could simply be a coincidence that cosmic rays are at the maximum when the sun is at its weakest.

    It just so happens that the low level of solar activity both allows more cosmic rays in and alters the vertical temperature profile of the atmosphere (via different rates of ozone reactions at different levels) at the same time.

    I think the real reason for more clouds when the sun is less active is more meridional jets looping about with longer lines of air mass mixing causing more global cloudiness and higher albedo for less energy entering the oceans to produce overall system cooling.

    If people prefer the Svensmark hypothesis to that, please could they explain why ?

  23. tchannon says:

    If you look there are many papers on tree ring findings.

    A couple I have seen and lost involve complete instrumentation of several Siberian Larch (IIRC), bad news for certain people.

    Here is another with a simple result: –

    An analysis was performed of the climatic responses of the radial growth of Larix
    gmelinii (Rupr.) Rupr. at two sites, both of which included contrasting north- and
    south-facing slopes, in Tura, central Siberia, with the development of ring width and
    maximum-density chronologies for each slope. Both residual and standard
    chronologies of ring widths were positively correlated with temperature from late May
    until mid June on all four slopes. By contrast, standard chronologies of ring widths
    were negatively correlated with precipitation during the winter (from October to April)
    and in May on the north-facing slope at site one and on the south-facing slope at site
    two, respectively. The negative correlations with precipitation during the winter and in
    May on some of the slopes suggested that delayed snowmelt in early spring might
    inhibit the radial growth of L. gmelinii, and the effects of snow are likely to vary with
    topography. Both residual and standard chronologies of maximum densities were
    positively correlated with temperature in early July on all four slopes. Maximum
    densities were also positively correlated with precipitation during summer of the
    previous year on all the slopes. These suggest that no major differences exist in terms
    of responses of maximum density to climatic factors between the north- and
    south-facing slopes.
    Key words: Larix gmelinii, Siberia, climatic response, ring width, maximum density ”

    Ecological Research. 22(4):582-592 (2007) (from Shinshu University, Japan)

    Not the previous season precipitation response for width, but maximum density is more reasonable. However I add that from other papers I have seen the temperature effect tends to be very narrow in time and might have two sensitive periods with contradictory response. I also point out that such narrow thermometer data is never available, moreover weathers sites tend to be far too far from the tree.

    I can also indicate web resources containing many photographs of Siberian forest monitoring conditions for trees throughout the year. (such as 10 day) I don’t think this adds a great deal.

  24. adolfogiurfa says:

    @Stephen Wilde: That “coincidence” seems to indicate that, at least, the Sun reached its “first” maximum this year:

  25. Tallbloke, has anyone a link to the Sigrid Dengel paper? The abstract is not helpful and the full article is behind a pay wall. Maybe someone could supply an email address so I could contact the authors.
    I do not believe the comment about methane contribution to the atmosphere (click my name and also read the replies). I wonder if they used the exaggerated IPCC value of 21 times CO2
    I recently also saw article about have quickly the effects of the blowout of the gas well in the Caribean disappeared. It seems that organisms in the oceans take up methane and light oil quicker than previouisly thought.

  26. tallbloke says:

    Good discussion!

    Michele: if the Dengel theory is right, much of that extra growth is due to the Solar cycles getting stronger after the weak cycle at the start of the C20th.

    Roger and Tim: Good info and summaries – thanks.
    Stephen, keep developing the ideas, I think you may be right.

    PG: your lifetime of acute observation is appreciated.

    Adolfo: Yes, there’s a peak in GCR. Time will tell.

    CaF: We haven’t covered methane here, wanna do a guest post?

  27. Roger Andrews says:

    Stephen Wilde:

    “I think the real reason for more clouds when the sun is less active is more meridional jets looping about with longer lines of air mass mixing causing more global cloudiness and higher albedo for less energy entering the oceans to produce overall system cooling …. If people prefer the Svensmark hypothesis to that, please could they explain why ?”

    I don’t see why your hypothesis is incompatible with the Svensmark effect. Why couldn’t the two act together?

  28. Stephen Wilde says:


    That is possible and I have given it some thought but eventually decided that at best it might just be a supplementary effect.

    My reasoning was that the cosmic ray quantities would be pretty much evenly spread globally so I couldn’t see how they could affect the vertical temperature profile of the atmosphere so as to make the jets more meridional and expand the polar air masses.

    Furthermore there are so many particulates in the atmosphere anyway that I didn’t see how some more would have much effect.

    My mind remains open but at present I think my idea is to be preferred.

  29. tallbloke says:

    Stephen, GCR’s are absolutely not spread evenly over the globe in terms of the strengths required to penetrate to the lower troposphere. The effect should be stronger at higher latitudes.

  30. Stephen Wilde says:

    Rog, that deals with one point then 🙂

    Could cosmic rays affect the behaviour of the downward flow of cold air through the polar vortex ?

    Let’s look at the difference between the polar vortex when the sun is active:

    A single strong high pressure cell over the pole and the permanent climate zones shifting poleward (positive AO)

    With the situation when the sun is less active:

    An area of relatively low pressure over the pole with several high pressure cells around the pole which move equatorward as observed by Marcel Leroux (negative AO).

    To account for that we need something that intensifies that polar high pressure cell when the sun is active and breaks it up when the sun is less active.

    I think that to achieve that we need extrra warmth to develop over the pole in the stratosphere when the sun is inactive so as to obstruct, divert and split up the downward flow of cold air into a number of seperate components, one for each high pressure cell around the pole.

    Joanna Haigh found that when the sun was less active between 2004 and 2007 ozone quantities INCREASED above 45km which implies warming up there.

    Would that then split up the downward flow ?

    I think so.

    Meanwhile the stratosphere has stopped cooling since the late 90s and may now be warming a little. Contrary to established climatology.

    So what we have here when the sun is less active is different ozone reactions at different levels affecting the vertical temperature profile of the atmosphere over the poles, generating multiple Mobile Polar Highs and pushing cold polar air down across the mid latititudes generating more meridional jets, more clouds, less energy into the oceans and overall system cooling.

    I think the top down effect is due to ozone chemistry varying above and below 45km and not cosmic ray quantities.

    Meanwhile those Mobile Polar Highs and loopier jets have an effect on Vuk’s North Atlantic Precursor and then as Vuk says on the AMO but the primary forcing agent is in my opinion those ozone reactions above 45km.

    When the sun is more active ozone above 45km declines, the mesosphere and stratosphere both cool, the polar high pressure cell withdraws to above the pole because there is no longer any mesospheric and stratospheric warming obstructing the downward flow, the jets (indeed all the permanent climate zones) shift poleward. global cloudiness reduces, more energy gets into the oceans and there is net system warming.

    However the beauty of it for life forms is that whether the system is warming or cooling the speed of energy throughput changes via the water cycle to prevent or minimise any large changes in total system energy content.

    Vuk is correct as regards the bottom up effect but not as regards the top down effect.

  31. tallbloke says:

    Stephen, i understand your logic, I just worry we will have difficulty testing your hypothesis with the available data.

  32. Stephen Wilde says:

    I agree, Rog. That is why I am reconciled to a wait and see approach.

    I’ll probably be dead before the necessary data becomes available but I’ll try to hang on 🙂

  33. Stephen Wilde says:

    Actually, on reflection, all we need is stratospheric/mesospheric warming whilst the sun is inactive.

    If that happens then I have the only game in town.

    If it doesn’t happen then I have a problem but on some accounts there has been a slight warming since the late 90s:

    “The evidence for the cooling trend in the stratosphere may need to be revisited.
    This study presents evidence that the stratosphere has been slightly warming
    since 1996.”

  34. P.G. Sharrow says:

    @ Stephen; As the air cools in the far north it gets dense and sinks, pressure rises. When I lived in Alaska the interior would get 40F to 60F below 0. The coast fiord that I lived in almost penetrated the mountain range. Out in Prince William Sound It might be a clear sunny day and a warm “high pressure area” over the gulf of Alaska. Still there would be super cold, gale force winds blowing out of the pass and fiord and a fog bank traveling out over the ” warm (32F above 0) sea water and air temperature of 40F plus.
    Cold dry high pressure air from the interior blowing under the warmer high pressure air of the Gulf of Alaska. Pressure and density are not necessarily the same thing due to temperature difference.

    Energy that is accumulated over the waist of the earth on land and in the oceans leave via the polar regions. Cooling fluids get more dense and sink, surface pressure rises as the weight accumulates even though the cooling air contracts and creates a ” low pressure” area aloft. pg

  35. Stephen Wilde says:


    Is that necessarily inconsistent with my suggestion as to how the descending polar vortex behaves as a result of differential ozone reactions at different levels higher up in the atmosphere?

    I see the phenomena you describe as simply being overlaid on the background process that I described.

  36. P.G. Sharrow says:

    Stephen, I am not sure as to cause or effect on ozone creation and the polar vortex. In the early days of the “polar ozone holes” discovery, the proposed cause was that the super cold vortex was the cause of the ozone holes. This was later ignored by “the team” as they jumped on the HCFL band wagon as the cause of the depletion. Personally, in my opinion the science pointed to the cold what done it.

    The oceans put up huge amounts of chlorides into the atmosphere every day. I doubt that humans could create enough hydro-cloro’s to have any important effect. On the other hand the sun creates and destroys huge amounts of ozone every day due to radicalization of the molecule’s atoms. After all, the UV shielding of ozone is due to it’s absorption of the UV energies as it is broken down.
    Sunlight creates ozone, mostly over the central latitudes, it travels toward the poles high up along with the high stratospheric airs and sinks over the poles along with the super cooled atmosphere into the polar night. As the amount of ozone is depleted along the way into the polar vortex a “hole” more or less is seen.
    SO I am not sure that the depleted condition of the polar stratospheric airs is a cause or effect of the super cooled nature of the polar vortex.
    I am sure that the nature of the north and south magnetic lines of force are different in their effect on all matter that they pass through. pg

  37. suricat says:

    SW & PGS.

    Do I need to remind you guys that ‘Climate Cells’ are mainly produced by the dynamical inertial input at the ‘boundary layer’ and are generated, for the most part, by the Earth’s rotational vector.

    Boundary layer ‘mist’ greatly increases the ‘mass density’ of the atmosphere there, thus, improves the ‘planar centrifuge’ effect near Earth’s poles (the Earth’s surface effectively ‘pumps harder’ to generate a more powerful Polar Cell)! The ‘origin’ of the AO fluctuation ‘must’ be at the Earth’s ‘surface’ (fluid dynamics).

    To me, this seems proportionately in agreement with GCR propensity.

    Best regards, Ray Dart.

  38. P.G. Sharrow says:

    Hi Ray, “climate cells” are a creation of climate bureaucrats along with “grid cells”. 😉 on the other hand;

    “the ‘planar centrifuge’ effect near Earth’s poles (the Earth’s surface effectively ‘pumps harder’ to generate a more powerful Polar Cell)! The ‘origin’ of the AO fluctuation ‘must’ be at the Earth’s ‘surface’ (fluid dynamics).”

    is beautiful to me 😎 pg