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Ozone impacts on climate change

Filed under: — gavin @ 27 July 2007

In a nice example of how complicated climate feedbacks and interactions can be, Sitch and colleagues report in Nature advance publication on a newly modelled effect of ground level (or tropospheric) ozone on carbon uptake on land (BBC). The ozone they are talking about is the ‘bad’ ozone (compared to ‘good’ stratospheric ozone) and is both a public health hazard and a greenhouse gas. Tropospheric ozone isn’t directly emitted by human activity, but is formed in the atmosphere as a result of photolytic reactions related to CH4, CO, NOx and VOCs (Volatile Organic Compounds like isoprene, benzene etc.) – the so-called ozone precursors.

It’s well known that increased ozone levels – particularly downwind of cities – can be harmful to plants, and in this new study with a carbon-climate model, they quantify how by how much increasing ozone levels make it more difficult for carbon to be sequestered by the land biosphere. This leads to larger CO2 levels in the atmosphere than before. Hence the ozone has, as well as its direct effect as a greenhouse gas, an indirect effect on CO2, which in this model at least appears to be almost as large.

Actually it’s even more complicated. Methane emissions are one of the principal causes of the rise of ozone, and the greenhouse effect of ozone can be thought of as an indirect effect of CH4 (and CO and VOCs). But while NOx is an ozone precursor, it actually has an indirect effect that reduces CH4, so that the net impact of NOx has been thought to be negative (i.e. the reduction in CH4 outweighs the increase of ozone in radiative forcing – see this paper for more details). This new result might prompt a re-adjustment of that balance – i.e. if the ozone produced by NOx has a stronger effect than previously thought (through this new indirect mechanism), than it might outweigh the reduction in CH4, and lead to NOx emissions themselves being a (slightly) positive forcing.

In a bizarre way this is actually good news. There are plenty of reasons to reduce NOx emissions already because of it’s impact on air pollution and smog, but this new result might mean that reductions wouldn’t make climate change any worse. It also, once again, highlights the role of CH4 (the second biggest GHG forcing), and points out a further reason (if that was required) why further methane reductions could be particularly welcome in moderating future changes in climate and air quality.


243 Responses to “Ozone impacts on climate change”

  1. 1
    John says:

    “CH4 (the second biggest GHG forcing),”

    Isn’t water vapor the predominant greenhouse gas?

    [Response: It’s not a forcing – gavin]

  2. 2
    Henry says:

    Just to be pedantic. It should be “principal causes”.

    [Response: fixed. thanks -gavin]

  3. 3
    Reasic says:

    Nice post. I saw the BBC article and was going to post on it, but haven’t had the time. Now I’m glad I waited, as your article will provide valuable insight. Thanks.

  4. 4
    Timothy Chase says:

    I understand that there are some climatologists who believe that at least in the short-term, methane should actually be a greater focus than carbon dioxide. In essence, by working on this front, we could buy some time in the reduction of carbon dioxide. Additionally, the success which we have made in terms of reducing our methane emissions so far does not appear to have been especially costly or difficult. Improvements in farming practices, properly sealing pipes, etc.

    How does this work in terms of doubling? To what extent has increases in methane been responsible for the change in the world average temperature that we have seen so far?

    Likewise, I understand that Hansen has argued that black carbon has been at least as important are carbon dioxide in the loss of Arctic sea-ice. In the near-term, reductions in black carbon emissions could be quite important.

    PS Not sure what the problem is, but in my IE6 the bronze column is partly covering the textbox today. I believe the textbox is considerably wider than normal.

  5. 5
    Jack Roesler says:

    One way to reduce mankind’s CH4 emissions is to adopt vegan diets. No animals raised for food means far less CH4 released from farming, manure, and animal flatulence and burping. A tremendous side benefit would be much healthier people.

    I’ve been on a mainly vegan diet for about 12 yrs now, and would never go back to my old animal foods-based diet. My cholesterol is only about 144, my BMI is about 21.5, and all other vital signs are well within the normal range. I’m 67, have a recently diagnosed mild case of cystic fibrosis. Now that I’m being properly treated for that condition, am healthy as can be. No more constant bronchitis. The vegan diet, I believe, has sustained me through 14 yrs of bronchitis.

  6. 6
    Lawrence Brown says:

    Even though ozone isn’t produced directly by human activity,the methane contribution to ozone, has a number of anthropogenic sources, such as emissions from sewage treatment plants, mining leaks, rice paddies, the leakage of natural gas pipelines, and landfills( which could be cut substantially if more waste were recycled).

    Steps can be taken in these areas that could cut down on CH4 emissions, and it would seem to be worthwhile to do so to mitigate climate change since CH4 is much more effective greenhouse gas on a molecular basis than CO2,even though it’s less prevalent and has a shorter atmospheric lifetime.

  7. 7
    S. Molnar says:

    Re #5: I fear the vegan diet only helps with GHGs if you don’t live a lot longer as a result, since your very existence in the modern world almost certainly contributes to the problem. I think I’ll eat lots of cheese and die young of a heart attack. It’s the least I can do to help.

  8. 8
    Eli Rabett says:

    Or you can change the animal’s diet.

  9. 9
    Marco Parigi says:

    Can anyone tell me what the pre-industrial atmospheric concentration of methane is?As well as being easier than CO2 to reduce anthropogenic CH4, it is also easier to capture from natural sources.

    [Response: About 700ppb (today’s value is close to 1750 ppb). – gavin]

  10. 10
    Cat Black says:

    There are those that hold out for trees and tree planting to save us from our sins. Yet our sins, it seems, have rendered our photosynthetic allies less useful than we’d hoped, perhaps not even as well as has been modeled. And thus by degrees we paint ourselves ever more tightly into our cramped little corner. Little left now but to change our ways. I wonder… what are the chances of that? And while we have fewer options all the time, political leadership are not apparently disturbed into meaningful actions.

    If one were to conceive a trap for a technological society, they could have done no better than the trap we are currently caught in. We are stuck in our patterns, and thus we walk in lock-step over a cliff knowing full well what is happening to us.

  11. 11
    B Buckner says:

    Since ozone levels have actually been dropping in the developed world for 20 years or so, shouldn’t the focus of the paper have how this helps the climate rather than the potential damage from a modeled increase? Methane concentrations have leveled off and nox and voc levels are down substantially.

    Re: #5&7. The obvious answer is cannibalism. We get to eat our meat, reduce population, and shorten lifespans. A win win. :)

    Re: #6 Methane emissions are no longer allowed from landfills in Europe and the US.

  12. 12
    Linda N says:

    Would anybody from Real Climate care to comment on a recent article by Schwarz,Charlson and Rodhe in Nature Reports June 27, “Quantifying Climate Change- too rosy a picture?”? http://www.nature.com/climate/2007/0707/full/climate.2007.22.html
    Thanks for a great site.

  13. 13
    Mike Donald says:

    I spotted the BBC’s post so neat timing.

    Here’s my favourite stat on Ozone. If the Ozone layer was at sea level it would only be 3 millimetres thick – the thickness of a pound coin.

    Dive in with your own favourite coin.

  14. 14
    Roger William Chamberlin says:

    Man-made ozone [albeit manufactured in indirectly through emissions of other gases] also affects the oceans , because much of man’s pollution is in near-coastal cities and much of the seas’ productivity is focussed at the coasts , and the response time for phytoplankton to die is much shorter than land plants…

    Also phtoplankton get arond the seas by being bourne by the winds in clouds , they live in the clouds and seed the oceans from there [and lakes and rivers for that matter) ,this is how they get around the earth and many have UV absorbing pigments to give them long lifetimes in the clouds …

    This is something which climate models seem to have ignored, but the UV absorption by phytoplanktom influenecs the climate, changes the temperature profile in clouds and simplifying models by ignoring this factor simply must give the wrong answers [bearing in mind the instabilities from positive feedbacks of many varieties, physical, chemical, biological,all-too-human, …]

    We now know that phytoplankton have controlled [in co-operation with other life-forms] the temperature of the earth way below the purely physical models would predict for aeons of time before mankind arrived on the scene , this recent ‘paleo-science’ thus conclusively proves that climate models must be made more sophisticated , including all major biological influences, including plankton in the clouds, to have any hope of being predictive, the effect is just too massive to be ignored in simplification of the modelling .

    Phytoplankton also synthesise and emit dimethyl sulphide, a gas which interacts with atmospheric gases to generate sulphate nuclei in the air, potent cloud-generation by living organisms with a reason for their major investment in this seemingly unuseful gas to their immediate metabolism… they do so when under stress from lack of iron [a necessary trace element for them which is i very short supply in the seas because it precipitates out and is lost from the surface very quickly, becoming unavailable tp phytoplankton who live in the light of the surface of the ocean only…

    There is then a complication of man-created ozone in the dynamics of cloud creation and distribution on the planet…

    It comes back to the most pressing need of mankind which has not been fully recognised yet, that we are killing the oceans from out too rapid usage of fossil fuel;s to make life ‘easy’ for us in the short-term , the effect is likely to be mostly from CO2 which has already acidified the oceans and is killing the base of the food webs, the corals and phytoplankton , so that all life is slowly dying in the seas because of our industrialisation of huamn activities …

    Besides killing off our fisheries eventually, we are also killing off our main safe place to put the CO2 back into, the potentially much larger biomass of sea [and land] lifeforms ,where it came from in the first place [that is why we know it is the safest place for the CO2 , it is a method tried and tested by nature long before we came along – it works, so long as one does not kill off the very things one needs to make it work!]

    Worse still, killing off the oceans only adds further methane and CO2 to the air since dead life eventually decays if there is no life left to consume it [hence the insanity of putting CO2 underneath or on the sea-bed as some seriously propose, it would kill the life down there, some of it as much as 300metres below the seabed surface
    and craete insoluble long-term problems when the CO2 re-emerges eventually]

    Man has gleefully exploited what nature left us as a legacy in oil, without caring to do anything about recycling what we use or realising the terrible impact on us, now much-committed in infrastructure to the ‘easy’ life, whhen the artificially maintained low ‘price’ of oil can no longer be maintained because ‘demand’ exceeds max poss supply … we have behaved like spoiled brats on the earth and if we do not change and become as inteligent as we like to think we are, then our future is very troubled indeed and inceasingly more likely to be impossible for humans to live… It is thus not prudent that we still talk about things and take no action to cease behaving like uneduicated brats in our way of life , people need leadership to change our whole infrastructure and way of living to something which can last…

    If one thinks about it but a short while, sustainability is NOT optional, it is a requirement … but it is not made a requirement of governments put in term for just a few years …

    we are getting what we instituted to get in our lives, but people will not insist on sustainability until they see that it is necessary for themselves and their children and their childrens’ children … making the models good enough then is a primary task , else even the best fall under the welter of propaganda put out by those who think we do not have to change in order to live a sufficient lifestyle on this earth.

    Since ew cannot have perfect knowledge before we begin to ACT ,we must have restraining control and close monitoring of our actions to ensure that they do not do more harm than good … one major advantage of providing the missing trace elements [mostly just iron] to bring the deadand dying seas to life, is that it is reversible to very great extent since simply ceasing to give iron causes the sea to revert to its previous dead state … it allows a dynamic monitored solution to getting the CO2 back into biomass where we know the earth can cope with it.

    Strangely enough we would all live healthier lives WITHOUT the petrol-driven car , so one could hope that the oil price becomes realistic even more quickly than it is so that this vast hazard to short-term and long-term health of all of us dies out quickly… sadly few people realise that every car on teh road could be responsible for seven deaths in the future according to one model I developed … assuming, as many do, that tomorrow will e much like today, really is an imprudent way to live which could very conceivably not only cost much life on earth its existence, but spell the chnage of civilisation for man back to just smallis local communities living much in isolation from each other, much like in the past…not from choice, but from necessity … and the earth then supports far fewer people than today …

    It does not seem worth taking the very describable risk of this happening for sake of the inaction we see today , but equally those trying to make perfect models of how tings work will also run out of time [and cheap oil] todo their research … we are complacent today in our industry and life support , but it is very largely fully dependent on cheap oil [which is already showing that it will never be cheap again, but will keep rising in ‘price’]

    This site and forum does good work indeed in spreading the truth to combt the endless propaganda of ‘dinosaurs’ [who believe the ‘growth paradigm’ still, desp[ite the evidence already that it is a short-sighted and inefficient principle , thsu incompatible with sustainable life of men and other animals ,and plants!] ,but the dynamic question is can it spread the word fast enough and are minds open enough to change to learn and act on the truth before we have killed our seas and have no way to a sustaiable life left… ?

  15. 15
    Bird Thompson says:

    Animal farming accounts for 18% of GHGs–more than transportation. (UN Food & Agriculture Organization) One thing we can all do is eat less animal-based meals. Eating vegan vs eating animals, in terms of the impact on climate change is like riding a bike vs driving a Hummer.

    The resistance to changing diet is huge. Sierra Club, Al Gore, etc. don’t even mention the vegan option in combating global warming. We must expand our imagination to see the cause & effect relationship between our life habits & the dying planet. The mega-corporations that take grain & water to feed to animals don’t want you to know how much methane they produce or how it affects the climate. They want you to eat more burgers & drink more milk.

    We are in an emergency situation. We must act on all levels to reduce GHGs, including changing our personal habits & cultural traditions of eating.

  16. 16
    tamino says:

    Relying far less on animal husbandry (i.e., eating less meat) doesn’t require going all the way to “vegan.”

    It’s possible to drastically reduce one’s intake of animal products without quitting entirely. Eating meat only a few times a week, emphasizing seafood over beef, expending the effort to secure meat products that are much more local than intercontinental, all will reduce the energy requirements (and therefore greenhouse gas emission) involved in animal husbandry.

    And while a vegan diet brings undeniable health benefits, strict adherence to a strictly vegan diet over the long term also carries certain health *risks*. Moderation, rather than extremism, is likely to be more effective, and vastly likely to win more converts.

  17. 17
    Nick Gotts says:

    Re #15 [The resistance to changing diet is huge.]

    Yes indeed, it’s interesting how even on this site, there’s what appears to be a defensive resort to levity (#7, #9), or proposing measures which would have much less effect (#8), when this is suggested. (I’m a lacto-ovo-vegetarian with occasional fish-eating, I’ve reduced the animal-derived content of my diet considerably over the past few years, but I hereby promise to shift further in a vegan direction from now on.) Methane production is not the only issue: large amounts of tropical forest have been and are being cleared to ranch cattle, and to grow soya to feed them in intensive systems elsewhere.

  18. 18
    See - owe to Rich says:

    This is just my 2nd posting on climate matters, and as I’ve only been studying this for 2 months part time, and am not a climate scientist but merely a Ph.D in mathematical statistics, aficionados can take my views with a pinch of salt if they wish. Certainly, I am extremely impressed, and somewhat humbled, by the wealth of knowledge both here and on ClimateAudit.org. Even so, I am hoping that a posting from an outsider may have some value in summarizing the central issues.

    Accordingly, I am going to ask 4 questions here, and then discuss the relevance to these of 3 recent papers.

    I have to say that I am certainly in two minds on the issue of the extent of Anthropogenic Global Warming (AGW) – I do worry that in central England clear winter skies no longer guarantee frost the way they used to do, but from studying climate data I also find it difficult to believe in the IPCC’s central projection of a 3C increase during this century. In other words, I am not yet convinced that the CO2 effect will be as large as claimed.

    The crucial questions, modulo changes to my chosen time intervals, seem to be along the lines of:

    Q1: what degree of global warming actually occurred between 1970 and 2000?

    Q2: how do we apportion this between CO2, the Sun, and other causes, and therefore how much is a doubling of CO2 worth?

    Q3: how much warming will occur over the next 100 years?

    Q4: how good, or bad, will this warming be for the world?

    These questions are fairly simple to state, but furiously difficult to answer, apparently. I am not going to attempt that here, but merely discuss them.

    For Q1, some would argue that a different interval should be studied, but the CO2 brigade (to distinguish from the “solar brigade”) have a valid question as to why it warmed significantly in that period – about 0.4C according to the ‘hadcrut3′ figures. But as an outsider I find it deeply disappointing that the physical basis for the accuracy and fairness of the quoted data is in some doubt for some of the terrestrial stations. Nevertheless I do not find it necessary to invoke a conspiracy to account for this – I have always believed in the cock-up version of history (sometimes with the occasional conspiracy to cover up the cock-up). I believe that it is important to establish a non-controversial set of data, for example from rural sites with thermometers placed a good distance from air conditioners etc.

    Q2 is the biggy (insofar as it impacts Q3, which is where the politics come into play). In the CO2 brigade it may be possible to find claims as high as 125% for the CO2 effect – i.e. the sun weakened in that time, so CO2 warming covered the 0.4C plus more for solar loss. In the solar brigade, it might be put as low as 0%, but some of this brigade allow it to be in the region of 25% (i.e. 0.1C out of the 0.4C). The modellers rate the CO2 effect at a very high level, but it is quite possible that God is playing a cruel trick on them – making the CO2 models fit well in this period but really using some different effect for most of the change. I shall discuss this more below.

    For Q3, even if we allow for 0.0133 = 0.4/30 degrees per year in 1970-2000, I don’t see how the IPCC can turn that into 0.03 degrees per year for their central 3.0C per century (or is it 92 years?). But I’m not an expert, so perhaps it comes from bits of modelling I cannot be expected to understand. The other thing about the 3.0C though, is that it ignores solar effects. I have seen no refutation of the association of the depths of the Little Ice Age with the Maunder Minimum of solar activity; further it appears that sunspot effects are greater than is the total solar irradiance (TSI). Now, if the Sun had been in an average state since 1960 or so, it would be reasonable for the IPCC to argue that over the next 100 years it might, on the whole, remain average. But Solanki et al have shown that the Sun has been in an unusually active state, and as with the housing market one might therefore be expecting a fall before 100 years are out.

    Regarding Q4, I have seen many and many more arguments on both sides. Personally, I am quite happy for England to be a little warmer, and I am happy if more CO2 helps all those beautiful plants to grow. But my house currently (27/7/07) has no tap water, and the stream through our garden rose 5 feet to a torrent, coming within a couple of inches of our floorboards. Was that caused by global warming? The Met Office tells me that it probably was. On the other hand, the last time the River Severn got almost as near to Tewkesbury Abbey, in 1947, was at the onset of a period of global cooling, and there were several famous floods in the 50’s too. And the time when it got *really* high, in 1760 when the canon of the Abbey was rowing along the aisle rather than merely paddling, was – well I don’t really know, but it wasn’t during CO2-induced global warming. Warming followed by cooling (globally) is arguably the best recipe for heavy rains – just like with a cold front (locally), you have warm moist air precipitated by cold air.

    Moving on to the 3 papers/talks, I want to start with Green and Armstrong. Here in RealClimate they have been criticized for translating their forecasting criteria formulated in the econometric world to the climatic world, as if that’s a bit of a dirty trick. As an interested outsider, I think that forecasting is forecasting – there are data, models, parameters, and errors between the data and the models. I don’t care if the models come from physics or economics, I just want a sound forecast. I am amazed that there could be so many forecasting principles as they claim, and I wonder how many forecasters in any sphere of life could pass a test of so much red tape. Nevertheless, if real climatologists want to convince me, then they need to answer the searching questions posed by that paper of Green and Armstrong; as others have said, they are at liberty to give their own versions of scores if they can demonstrate that G and A’s ignorance of climatology led to unreasonable assessments.

    The second paper is Lockwood and Frohlich. I found this really interesting reading, and it certainly notched my personal CO2 brigadometer up a bit for a few days. But then I thought, if very little of the 11/22-year solar signal comes through in global temperatures, what effects there are must be smeared over longer time spans. So if the sun was extra active from (say) 1910 to 1985, then with the smearing time lag, one would expect global temperatures to rise beyond 1985, flatten off, and then fall. There’s a lot of argument over whether 2001-2007 data represents a flattening, but that’s the way it looks to me. I would be tempted to argue that this British summer represents a cooling, but that would be parochial, since it’s hot in Eastern Europe, and ‘hadcrut3′ is still holding up reasonably.

    The third item is slides from David Archibald’s talk in Melbourne in June 2007. I had never seen this relationship between solar cycle length and temperature before – that an early (late) onset of a solar cycle is correlated with an increase (decrease) in global temperatures. There are things I don’t understand about this, especially the time lag, so I am trying to follow up some of the references to understand more. Possibly Archibald is over-egging it, especially since there are wide variations in the predictions for the sunspot count in Cycle 24, but a real downturn in the Sun would be a wonderful test between the two brigades. Lockwood and Frohlich say the Sun turned down from 1985 onwards, but by the measure of cycle length, Cycle 23 started earlier than average in 1996, so it can only be after Cycle 24 starts late (probably around 12.0-12.5 years compared with a mean 10.6) that there will be a concensus that the Sun is on the way down. Then, if the temperatures do not dip by as much as Archibald predicts (for given lateness of cycle), or even increase, we will be able to get a better estimate of how much effect a doubling of CO2 really has. And then we shall know whether they are right, those correspondents on this site who share thoughts of the ilk “Lockwood and Frohlich have banged in the last nail in the coffin of the solar theory of global warming”.

  19. 19
    tamino says:

    Re: #18 (See – owe to Rich)

    I too am a statistician (my specialty is time series analysis), and I confess that certain aspects of your post puzzle me. There’s too much covered to ask all my questions in a single response without begin excessively long, so I’ll start at the beginning. You say:

    Q1: what degree of global warming actually occurred between 1970 and 2000?

    … about 0.4C according to the ‘hadcrut3′ figures.

    … even if we allow for 0.0133 = 0.4/30 degrees per year in 1970-2000

    How did you arrive at these figures? Straightforward linear regression of HadCRUT3 data from 1970 to 2000 gives a slope of 0.016 deg.C/yr, not 0.0133, and would imply an overall warming for the three decades of 0.048 deg.C, not 0.4.

    For Q3, even if we allow for 0.0133 = 0.4/30 degrees per year in 1970-2000, I don’t see how the IPCC can turn that into 0.03 degrees per year for their central 3.0C per century (or is it 92 years?). But I’m not an expert, so perhaps it comes from bits of modelling I cannot be expected to understand.

    Your estimate of 0.0133 deg.C/yr as the “present” warming rate (or even the rate from 1970 to 2000) is considerably in error. Furthermore, since 1970 global warming has shown statistically significant acceleration. The overall rate over the last 30 years is more like 0.018 deg.C/yr, and the rate since the year 2000 is 0.020 deg.C/yr according to HadCRUT3, and a whopping 0.031 deg.C/yr according to GISS. As you say, you’re not expected to know the details of the physics or the models, but as a statistician, I do expect you to know these details. So again — I’m sincerely curious — how did you arrive at your figures?

  20. 20
    Lynn Vincentnathan says:

    Good post. It’s along the lines I’ve been thinking from the beginning: we need a holistic approach.

    I’d been mainly telling people, that measures to reduce GHGs, also reduce lots of other pollution (which cause harm & death), and have other positive non-environmental benefits, like:
    1. saving money without lower living standards or economic productivity (up to perhaps a 3/4 reduction of GHGs or more)
    2. improving health/spirits and crime and taxes for road building/repair (by off-setting some driving with walking/cycling)
    3. reduce wars over oil
    4. etc

    But even the internal issue of GHGs & climate change are extremely complex.

    I know science trudges along slowly and gets to the complex picture only after dealing with the more simple pictures. But we can conceive that our world is indeed exceedinly complex….so much so that, as anthropologist Roy Rappaport suggested, we need to hold the environment in awe and respect. Because we don’t know it all (& perhaps never will), and we should be careful in our dealings with it.

  21. 21
    Michael says:

    Re #18. It is not obvious that global warming will be beneficial for plant life on earth. For example see http://www.newswithviews.com/Peterson/rosalind4.htm for an indication of how trees are dying. The critical condition of the amazon is well documented.

    In terms of your Q4, the situation we face is an emergency.

    It is a bit like driving a car on motorway at 70 mph and seeing a pile up in a front at a distance of 96 metres and knowing that your stopping distance is about 96 metres. One might be tempted to slam on the brakes.

  22. 22
    Paul says:

    I recently read something on the heretofore unperceived threat of water dimers. I am wondering if Gavin-or anyone-would care to comment on this issue.

  23. 23
    Steve Bloom says:

    Re #s 18 + 19: Uses of phrases such as “the wealth of knowledge both here and on ClimateAudit.org” and “CO2 brigade” give away the game, IMHO. A PhD in mathematics honestly approaching the climate change issue for the first time would know better than to engage in the sort of cherry-picking of evidence and out-and-out asyllogisms evidenced throughout #18. Tamino’s pointing out of some pretty basic stats errors are the icing on the cake.

  24. 24
    Chuck Booth says:

    Re # 18 a Ph.D in mathematical statistics

    I don’t mean to be flippant, but isn’t “mathematical statistics” redundant? Is there any kind of statistics that isn’t mathematical?

  25. 25
    Timothy Chase says:

    Paul (#22) wrote:

    I recently read something on the heretofore unperceived threat of water dimers. I am wondering if Gavin-or anyone-would care to comment on this issue.

    I hope that someone will comment on their specific application to greenhouse gas theory. Doing just a little research, I found that these weak hydrogen couplings between water molecules isn’t as well understood as we might like, and that part of the problem involves the interaction of the light hydrogen atoms with zero-point energy – that is, the virtual particle buzz thats always there even when space is “empty.”

    I suppose the uncertainty involved in its interaction with the zero-point might help to explain why is able to amplify the chirality of the weak force at roughly ten times the magnitude that was predicted, and perhaps why we are able to freeze at room temperature with an electrical field at one one-thousand the strength that had been predicted.

    Crazy stuff.

    Going off of what Eli wrote earlier this afternoon (A Saturated Gassy Argument, comment 306), it would appear that they result in additional dimensions in the phase space description of water as it exists in the transitory dimer state. And it appears to be a bit of a black hole in our knowledge for the time being, but would apparently operate in the far IR spectrum.

    At first glance a 2004 paper didn’t look that promising – but I am no expert.

    However, doing a little more digging, I ran across something which is clearly related and from the perspective of theoretical understanding looks quite promising – which I had brought up previously – although I didn’t have the paper at the time.

    Here is the write-up for it:

    Computing water’s quantum properties. Despite water’s centrality to life, its quantum properties are still not fully understood. Alexander Donchev et al. have developed a mathematical model that accurately describes water’s properties from first principles. The model may be useful for understanding water’s properties in a pure state and in biomolecular systems. Donchev et al. applied a quantum mechanical polarizable force-field model, which they had developed for studying organic systems, to the simulation of pure water. The model accurately calculated water’s thermodynamic and structural properties, including its unique density changes near 0 C. The model, which is based on quantum mechanical calculations for systems of small molecules and their dimers, showed as good or better agreement with the measured properties of liquid water than previous computer models devised strictly to fit those properties. The authors say that further refinement of the equations and parameters in their model should bring it even closer to reproducing water’s properties. The model may also be useful for understanding the interactions between water and organic molecules such as proteins.

    In This Issue
    Proc Natl Acad Sci U S A. 2006 June 6; 103(23): 8573–8574
    http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1482620

    The paper is free access to any and all on the other side.

    If you are interested in the other topics, you might check out the following:

    2006 (technical)
    P-Violation Manifested at the Molecular Level – A Simple Means for an Absolute Definition of “Left” vs. “Right”
    Avshalom C. Elitzur, Meir Shinitzky
    arXiv:physics/0601010 v1 3 Jan 2006
    http://arxiv.org/PS_cache/physics/pdf/0601/0601010.pdf

    Number 742 #1, August 19, 2005 by Phil Schewe and Ben Stein
    Room-Temperature Ice in Electric Fields
    http://www.aip.org/pnu/2005/split/742-1.html

    Oh, and an interesting implication of parity-violation…

    2005 (technical)
    Subtle differences in structural transitions between poly-L- and poly-D-amino acids of equal length in water
    Yosef Scolnik,et al
    Received 3rd October 2005, Accepted 21st November 2005
    First published as an Advance Article on the web 5th December 2005
    DOI: 10.1039/b513974k
    http://www.rsc.org/delivery/_ArticleLinking/DisplayArticleForFree.cfm?doi=b513974k&JournalCode=CP

  26. 26
    Timothy Chase says:

    PS (post #25)

    It should be obvious, but I was still tuning into KWTC when I started writing the post. A little of that all too common static. Or perhaps it has something to do with the structured water in one of my brain cells or within the hydrophilic catalytic core of some ribozyme…

    Who knows?

    The second sentence should read:

    Doing just a little research, I found that the weak hydrogen couplings between water molecules aren’t as well understood as we might like, and that part of the problem involves the interaction of the light hydrogen atoms with zero-point energy – that is, the virtual particle buzz thats always there even when space is “empty.”

  27. 27
    ChrisC says:

    Re: 18

    “The third item is slides from David Archibald’s talk in Melbourne in June 2007. I had never seen this relationship between solar cycle length and temperature before”

    Archibald’s paper, published in Energy and and Environment, was called by one commentator “The worst climate science paper ever, of all time, anywhere” (see: http://n3xus6.blogspot.com/2007/02/dd.html), and if you had taken the time to read it, as a PhD, you should have seen several of the most glaring statistical errors it is possible to make.

    Here are a few of the howlers:

    – Instead of using the world wide temperature, from say GISS or Hadley, he choses a total of five stations. Yes five, all in the within several hundred kilometers from each other in the South Eastern United States.

    – The stations chosen buck the trend of increasing temperatures in the later half of the twentieth century. The stations chosen indicate lower temperatures in the later part of the twentieth century, which is not reflected in the vast majority of stations worldwide. Since so few met stations were chosen, one has to wonder if they were chosen so that they would fit Archibald’s argument.

    – In order to predict the temperature response to the changing solar cycle length, he uses a single temperature station, (De Bilt in the Netherlands). Not even 5 stations. A single station.

    – He then decides that the correlation between De Bilt and the solar cycle length is good (but fails to mention the R^2 value, because the correlation is poor). He also uses cherry picks data from the complete set of temperature records from the station. This is misleading and wrong. When the full data set is used, the R^2 value
    for the correlation is only 0.0177.

    – Archibald then predicts a reduction in temperature of 1.5C over the next solar cycle. He claims he can do this due to correlation with cycle amplitude, but then presents a graph of solar cycle length to illustrate the correlation. He offers no explaination. He also has used very strange predictions of the solar cycle.

    In short, this paper is weak as starbucks coffee, and citing it is unlikely to earn you any credibility. As one who has studied stats, you should probably be able to pick these errors from the paper without difficulty.

    -

  28. 28
    Geoff Russell says:

    Re: #16 If you are in the US, then you can’t increase fish consumption unless some other country
    volunteers to decrease its consumption because the US is a net fish importer by about
    2.4 billion pounds — http://www.st.nmfs.gov/st1/fus/fus06/fus_2006.pdf
    Fish farming, as currently practiced (usually with carnivorous fish), is a net consumer of fish,
    not a producer.

    Re: #6. The list of anthropogenic methane sources omitted the biggest source: livestock.

    Researchers at Sydney University in conjunction with the Australian Conservation Foundation
    have recently put a very good eco-calculator on line. Pretend you live in Australia and
    see what influences your personal carbon footprint:

    http://www.acfonline.org.au/custom_atlas/index.html

    For most people on the planet (except the sort of people who perform at “Live Earth”) what
    they eat is the principle determinant of their own personal climate forcing footprint. This is
    usually obscured because most studies simply don’t follow the full production chain.
    Even the much publicised Japanese “Life Cycle Analysis” looking at the ghg emission intensity of beef
    stopped at the farm gate — no refridgeration, no abattoir costs, etc etc. It still found
    the emissions cost of a kg of beef to be about double that of aluminium.

    Lastly: back to #16, No you don’t need to be a vegan to lower you emissions substantially, just
    like I am not car-free, but I use a bicycle for most of my transport and my car is
    small and old. Lastly, given
    that vegetarians/vegans have lower rates of most diseases than meat eaters, then whatever these
    risks are, they are smaller than the risks associated with meat — like heart disease,
    colorectal cancer, the destruction of the amazon, etc.

  29. 29
    rojo says:

    re#21, your link is a giggle. Damn those jet contrails. Loved the references, and 5 year old tree photos.

    You were joking, Michael?

  30. 30
    J.C.H says:

    I’ll go with the vegan diet the day the vegans agree to shoot the 100 million cattle that call the good old USA home.

    And say goodbye to wool.

    And having human beings live longer does what to greenhouse gas production?

    And how many ruminants do countries that eat little meat have? Not eating them is enough. That really does nothing much at all. All the grain will still be needed for ethanol, so that won’t stop. Additional fossil fuels will be burned to add the mountains of vegetables that will be needed to replace meat calories. The net benefit is unlikely to be as advertised.

    How many greenhouse gases will all these long-lived people be producing when they’re vegetating in nursing homes until they’re 110?

    You have to kill ruminants them to stop them from belching.

  31. 31
    Timothy Chase says:

    Gavin: Improved Modeling of Tropics Temperatures?
    … and IR absorption by clouds?

    Laboratory measurements of water vapor absorption using cavity ring-down spectroscopy revealed a broad absorption at 405nm with a quadratic dependence on water monomer concentration, a similar absorption with a linear component at 532 nm, and only linear absorption at 570nm in the vicinity of water monomer peaks.

    The resulting estimation of 15–30Wm−2 could cause a difference of 4 C in the calculated average surface temperature of the earth (Carlon, 1979; Arking, 1996, 1999). Observations of this anomalous absorption found that the discrepancy was measurable in tropical regions and near clouds (Hill and Jones, 2000), but were complicated by the presence of scattering by particulates. Potential sources of the additional absorption include absorptions due to water dimer and water far wing continuum absorption. Water dimer has been calculated to absorb 3–6Wm−1 of solar radiation from calculations that used an outdated model for Helium clusters (Tso et al., 5 1998), and were then recalculated to be less (Vaida, 2001; Daniel et al. 2001).

    Water dimer absorption of visible light
    J. Hargrove
    Atmos. Chem. Phys. Discuss., 7, 11123–11140, 2007
    http://www.atmos-chem-phys-discuss.net/7/11123/2007/acpd-7-11123-2007-print.pdf?FrameEngine=false

    Exciting stuff… Just a guess, but this might help with modeling of the Indian Monsoon and the western edge of the Tibetean Plateau – which has been a bit of a problem for all models so far.

  32. 32
    James says:

    Re #30: [You have to kill ruminants them to stop them from belching.]

    Not that I’m buying into the “vegetarianism stops climate change” argument, but you don’t have to kill them all unless you want an immediate effect. You just stop letting them breed, and in a decade or two you’ll find the numbers greatly reduced.

    Of course you could short-circuit the vegetarian phase, and just apply the same logic to H. sapiens :-)

  33. 33
    wildlifer says:

    Just another reason for the denialists claims we should eradicate termites, rather than reduce emmissions. But there’s an even more ominous hurdle, from AnnCoulter sychophant:
    Mr.Magoo
    Location: California

    al-Gore and his tree kissing minions insult God with their global warming claptrap. They think the Almighty was stupid for putting sloppy SUV driving humans on this planet, when in fact He designed it and the universe to withstand just about anything humans could do.

    Mr Magoo was blind, wasn’t he?

  34. 34
    Lawrence Brown says:

    Re 33. wildlifer’s comment. The Ann Coulters of this world have one main interest;to draw attention to themselves, regardless of who might get hurt by the outrageous comments. It’s good for her book sales. I don’t know of anyone who has less credentials to call global warming “claptrap”.
    Plant species are migrating northward in the northern hemisphere, as are animal species. Does the cockroach have more of sense about global climate change than the Cockburn and Coulter. I’m afraid so.
    The subject of this latest article prompted me to read up on the strength of methane gas and I found that the enhanced greenhouse effect of a molecule of methane is about 8 times that of a molecule of CO2 (“Global Warming”- by John Houghton p. 42), but when an index called Global Warming Potential(GWP) is used,which measures the instant release of 1 kg of a gas to that of the release of 1 kg of carbon dioxide, then methane has a GWP of 23, since the atomic weight of methane is 16/44 or 36% of that of CO2(same source as above Table 10.2).This is for a time horizon of 100 years. GWPs have to be used with caution because GWPs for different time horizons are very different.

  35. 35
    Timothy Chase says:

    Paul (#22) wrote:

    I recently read something on the heretofore unperceived threat of water dimers. I am wondering if Gavin-or anyone-would care to comment on this issue.

    Paul,

    I believe this is what you were refering to:

    This transition peaks at 409.5 nm, could be attributed to 8th overtone of water dimer and the 532nm absorption to the 6th overtone. It is 10 possible that some lower overtones previously searched for are less enhanced. These absorptions could increase water vapor feed back calculations leading to higher global temperature projections with currently projected greenhouse gas levels or greater cooling from greenhouse gas reductions.

    Water dimer absorption of visible light
    J. Hargrove
    Atmos. Chem. Phys. Discuss., 7, 11123–11140, 2007
    http://www.atmos-chem-phys-discuss.net/7/11123/2007/acpd-7-11123-2007-print.pdf?FrameEngine=false

    It is from the article I mentioned in #31.

    The good news is that this is something climatologists can use to objectively improve the predictive power of climate models – assuming its real. And as Hansen has pointed out, they tend not to feel comfortable in suggesting the existence of vague threats – but only in stating that there exist certain well-defined threats which they can identify.

    If it is real, then it will be great that we have identified it sooner rather than later.

    It wouldn’t surprise me if we have made another one of those big discoveries regarding water. As I’ve said, its crazy stuff!

    [Response: Don’t get too excited. The dimer idea has come up repeatedly in the past as a solution to the ‘anomalous absorption’ issue that was all the rage a decade ago. Since then, most of the anomaly has disappeared (mainly due to improved understanding of aerosol effects), but the dimer idea persists. A brief conversation with our radiation people left me with the impression that the only substantial effects can be seen in the microwave region, which is irrelevant for climate purposes. This latest paper seems interesting, but there are a couple of howlers in the intro and conclusions (confusion of a short-wave absorption effect with the long wave water vapour feedback – SW effects do not contribute to the greenhouse effect!), and so I’d wait for the reviews to come in before assessing it’s worth. The biggest problem is that existing line-by-line models do a really good job of explaining what is seen either at the ground or at the surface, and so there isn’t any huge discrepancy that requires exotic new physics to explain. Having said that, this isn’t my field and I’m open to being corrected by people who know better. – gavin]

  36. 36
    Timothy Chase says:

    gavin (inset to #35) wrote:

    Don’t get too excited. The dimer idea has come up repeatedly in the past as a solution to the ‘anomalous absorption’ issue that was all the rage a decade ago. Since then, most of the anomaly has disappeared (mainly due to improved understanding of aerosol effects), but the dimer idea persists… The biggest problem is that existing line-by-line models do a really good job of explaining what is seen either at the ground or at the surface, and so there isn’t any huge discrepancy that requires exotic new physics to explain. Having said that, this isn’t my field and I’m open to being corrected by people who know better.

    Sounds good enough for me.

    I will let the experts worry about it, at least until they say there is something to worry about.

  37. 37

    Re #18, the writer seems to have some sincere but easily avoided misunderstandings. Instead of posting here, the writer should first read more carefully the basics, for example in the IPCC reports (it won’t take two months!). For me the first tipoff was in Q1, the phrase,

    “I believe that it is important to establish a non-controversial set of data, for example…” (etc.)

    The writer evidently is unaware of the enormous efforts by literally thousands of people to establish a land temperature record independent of urban effects etc. The writer is not even aware that one can leave out all the land-based data altogether, just use ocean data, and get entirely convincing evidence of the warming since 1970 and its relationship to greenhouse gases (since the pattern seen in the oceans cannot be explained by solar forcing).

    One could go on with the lack of knowledge shown elsewhere, but why bother. The writer should go and learn the basics before trying all this fancy number stuff.

  38. 38
    Timothy Chase says:

    Gavin (inset to #35) wrote:

    A brief conversation with our radiation people left me with the impression that the only substantial effects can be seen in the microwave region, which is irrelevant for climate purposes.

    I have run across some new stuff being found out there, but it makes sense that it would be more or less irrelevant with respect to climatology. Time to start digging for what they’ve found on aerosols.

  39. 39
    Phil Scadden says:

    Vegan diets arguments are complicated by nature of the meat production itself. If the beef is grain-fed or grown on lands that could be ploughed then this is an inefficient use of earths resources. On the other hand, I dont see many crop options for land around here where sheep are raised and the Soviet union had some disastrous forays into cropping steppe grazing lands.

  40. 40
    Michael says:

    Re 29. Whoops, wrong link. Trees in UK: see report “A Midsummer Night’s Nightmare” by Woodland Trust http://www.woodland-trust.org.uk/publications/publicationsmore/climatechangereport.pdf There are many other studies of specific species being impacted in different ways.

  41. 41

    [[Personally, I am quite happy for England to be a little warmer, and I am happy if more CO2 helps all those beautiful plants to grow.]]

    Will you be happy if European agriculture crashes due to droughts in continental interiors and more violent weather along coastlines? And would you be as happy if you lived in Bangladesh, or Florida?

  42. 42

    [[I recently read something on the heretofore unperceived threat of water dimers. I am wondering if Gavin-or anyone-would care to comment on this issue.]]

    Water dimers are the probable (not certain yet, I don’t think, although I could be wrong on that) cause of the “continuum absorption” in the big 8-12 micron IR window in Earth’s atmosphere. But their prevalence is most likely a function of the prevalence of water vapor in general in the atmosphere. I don’t see how you could reduce one without reducing the other. Or am I missing your point?

  43. 43
    Geoff Russell says:

    Regarding the various veggie arguments. The post was about
    ozone. Methane produces ozone in the troposphere and water
    vapour in the stratosphere. Its a triple nasty whether it
    comes from leaky gas pipes or livestock and suggestions to
    reduce livestock are as clear and simple as suggestions to
    fix leaky gas fields in the soviet union (and elsewhere) or
    drive less and be more energy efficient. What is it about
    suggestions to eat less meat that prompts such a defensive
    reaction?

  44. 44
    Marlowe Johnson says:

    I’m probably mistaken, but I thought that ozone’s main indirect GHG forcing effect was due to the fact that it retards the atmospheric decomposition of methane. It’s a pretty fascinating subject and I’m hoping that RC or a certain wily rabett can explain the dynamics in an idiot-proof manner…

  45. 45
    Nick Gotts says:

    Re #36 Yes, I think that’s pretty much right: if the only sources of meat and dairy were land that couldn’t be cropped (used for ruminants), and food waste (fed to pigs or chickens), then we’d see an enormous reduction in both methane emissions and animal suffering. One complication is the use of animals for labour and as sources of manure in many countries – not easy to find affordable substitutes, or ones that would not cause worse environmental problems, but as discussed on this site some while ago, there’s a lot of scope for reduction e.g. in India.

    Re #30 A fine example of the sort of defensiveness any suggestion of changed diets evokes.

    [I’ll go with the vegan diet the day the vegans agree to shoot the 100 million cattle that call the good old USA home.]

    I’d have no problem with that. Admittedly I’m not a vegan, and I imagine many vegans would, but even if you just stopped cattle breeding the problem would solve itself within a few years.

    [And say goodbye to wool.] The market for wool is in decline anyway – sheep are mostly kept for meat these days.

    [And having human beings live longer does what to greenhouse gas production?]

    So you’re against medical research, improved diets generally, reducing accidents and smoking, etc., I presume?

    [And how many ruminants do countries that eat little meat have? Not eating them is enough. That really does nothing much at all. All the grain will still be needed for ethanol, so that won’t stop. Additional fossil fuels will be burned to add the mountains of vegetables that will be needed to replace meat calories. The net benefit is unlikely to be as advertised.]

    For reasons discussed previously on this site, biofuels are almost certainly not a good idea from a GHG emission perspective, but if the grain were used for ethanol it would at least not be producing methane. As for the “mountains of vegetables needed”, this is just nonsense. It is enormously inefficient to grow crops to feed to animals and produce meat rather than for humans to eat directly. For cattle, I think the loss in terms of calories is about 90% – less for pigs and chickens but still substantial.

    [How many greenhouse gases will all these long-lived people be producing when they’re vegetating in nursing homes until they’re 110?]
    So is it mass suicide you’re advocating, or genocide?

    [You have to kill ruminants them to stop them from belching.]
    True, but the amount they belch depends on how much (and what) they are fed. Intensively reared ruminants are fed enormously amounts to maximise the rate of meat and dairy production.

  46. 46
    Nick Gotts says:

    RE #30 [I’ll go with the vegan diet the day the vegans agree to shoot the 100 million cattle that call the good old USA home.]
    Incidentally, notice the structural and emotional similarity to all the statements of the “I’ll take global warming seriously when Al Gore goes to live in a cave” variety, coming from what I’d call “amateur denialists” (members of the public making casual denialist comments).

  47. 47
    J.C.H says:

    RE #37 – Nick Gotts Says:

    You are way off base. I do not deny the science of global warming in any respect, and see little in it to be very skeptical about.

    Animal populations that are not harvested tend to increase in size, so a vegetarian diet is likely to result in more enteric fermentation, not less. You have to kill a ruminant to prevent its production of methane.

    And my family has supported Al Gore’s family politically since Al Gore was his father’s snot-nosed kid.

  48. 48
    James Walker says:

    Re: #28
    Are we individuals capable of influencing the state of the planet by our lifestyle choices or are we aggregates (countries) who must act in a unified fashion in order to have a positive effect?

    Quote:
    “If you are in the US, then you can’t increase fish consumption unless some other country volunteers to decrease its consumption because the US is a net fish importer by about 2.4 billion pounds — http://www.st.nmfs.gov/st1/fus/fus06/fus_2006.pdf
    Fish farming, as currently practiced (usually with carnivorous fish), is a net consumer of fish, not a producer.”

    You imply that if you eat fish and live in the US, the fish must result from aquaculture; furthermore you imply that all locations in the US suffer equally from a shortage of fish and must import it from other countries.

    Perhaps tamino lives in Vermont and decides to go trout fishing in the local stream on Fridays? Maybe he will hunt a moose, have it butchered, and freeze the meat to use for the rest of the year. Every one of us has to make judgment calls and decide how best to improve our lifestyle–based on our individual circumstances–to make a positive impact.

  49. 49
    J.C.H says:

    Also, recent research done on dairy cows in California indicates cattle fed quality diets produce less methane than grass-fed range cattle.

  50. 50
    Nick Gotts says:

    Re #47 True. But assuming this research is correct, which seems intuitively likely (ruminants house methanogens as part of a complex symbiosis with various bacteria that allows them to make use of cellulose), what follows? Whatever they’re fed on, the enormous numbers of cattle kept to provide people with meat and dairy products are going to be an important source of methane.


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