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Aerosols, Chemistry and Climate

Filed under: — gavin @ 12 July 2008

Everyone can probably agree that the climate system is complex. Not only do the vagaries of weather patterns and ocean currents make it hard to see climate changes, but the variability in what are often termed the Earth System components complicates the picture enormously. These components – specifically aerosols (particulates in the air – dust, soot, sulphates, nitrates, pollen etc.) and atmospheric chemistry (ozone, methane) – are both affected by climate and affect climate, since aerosols and ozone can interact, absorb, reflect or scatter solar and thermal radiation. This makes for a rich research environment, but can befuddle the unwary.

I occasionally marvel at the amount of nonsense that is written about climate change in the more excitable parts of the web, and most of the time, I don’t bother to comment. But in relation to the issue of aerosols, chemistry and climate, I read yesterday (h/t Atmoz) probably the most boneheaded article that I have seen in ages (and that’s saying a lot).

The hook for this piece of foolishness were two interesting articles published this week by Ruckstuhl and colleagues and a draft EPA report on the impacts of climate on air quality. First, Ruckstuhl et al found that as aerosols have decreased in Europe over the last few decades (as a result of environmental standards legislation), the amount of solar radiation at the ground has increased while the amount reflected to space has decreased. They hypothesize that this may have helped Europe warm faster in the last few decades than it would have otherwise done. Or equivalently, since the aerosols are anthropogenic, that European temperatures had been subdued due to the cooling effects of the aerosols – and since they are now decreasing, the full effects of the greenhouse gases are starting to be felt. This is just an update to the ‘global brightening‘ story we have touched on before. The EPA report is concerned with the impacts that climate change can have on atmospheric chemistry, and in particular the summertime peaks in urban ground-level ozone which are a well-known and serious health hazard. These are affected by local temperatures, cloudiness, temperature sensitive biogenic emissions and patterns of weather variability. Again, it is a story we have discussed before.

But the NewsBusters article succeeded in getting almost every aspect of these stories wrong. How do I correct thee? Let me count the ways.

  1. Aerosols are not smog:

    First they confuse aerosols with photochemical smog. Both are pollutants, but the first is dominated by sulphate emissions from coal burning power plants, the second from ozone precursors such as NOx, volatile organic compounds, and carbon monoxide mainly emitted from vehicles. (Note that ozone is not directly emitted, but is created by chemical reactions from the precursors with the addition of a bit of photolysis – i.e. sunlight-driven chemistry). The effects on climate are very different: ozone is a greenhouse gas, so increases cause a warming, while sulphate aerosols are reflective, and so increases cause a cooling. The air quality issues in the EPA are almost all focused on ozone.

  2. Europe is not the Globe:

    The next error is to equate changes in temperatures in Europe to the globe. While it would be true that if global aerosol levels declined it would lead to increased global warming, aerosol trends in Asia are increasing strongly, even while those in the US and Europe are dropping. The net effect is possibly a slight drop, but the impact on global temperature is as yet unclear. This regionality matters in both the sulphates case and for ozone. The relevant chemistry is sensitive to water vapour and temperature in varying ways as a function of the pollution level. In remote ocean areas, surface ozone will likely decrease as the globe warms for instance (due to increasing water vapour). In polluted environments increased temperatures and larger temperature-sensitive emissions of isoprene cause enhanced ozone levels.

  3. Surface ozone is not in the stratosphere:

    Next, NewsBusters asserts that the ozone story is confusing because of the

    .. treaty called the Montreal Protocol. This was designed to reduce and eventually eliminate the production and release of a number of substances thought at the time to be depleting ozone.

    Ummm…. those substances (chiefly chlorofluorocarbons – CFCs) are still thought to be depleting the ozone layer – which is in the stratosphere, some 30km above the ground-level ozone that people shouldn’t be breathing. CFCs have no impact on ground-level ozone at all (since their reactive chlorine is only released in the stratosphere).

  4. The final inanity:

    Wouldn’t it be fascinating if such efforts [such as the Montreal Protocol] lead to cleaner air around the world which ended up warming the planet, and that additional warmth is now breaking down the very ozone we thought we could save?

    Every part of this sentence is wrong. The Montreal Protocol had no impact on cleaning the air, it stopped the growth of CFCs which are powerful greenhouse gases (in addition to their role in depleting stratospheric ozone), therefore it slowed global warming, rather than increasing it, and we aren’t trying to save ground-level ozone. Had any of this been true it would indeed have been fascinating.

What should we make of this? Unfortunately one must conclude that no mistake is too dumb for someone, somewhere to make if they think they can spin it into supporting their anti-science agenda. For them complexity is something to be abused rather than a challenge to be understood, underlining quite clearly (again) the difference between science and propaganda.


356 Responses to “Aerosols, Chemistry and Climate”

  1. 201
    Ray Ladbury says:

    Rod B., If you want to warm up under your blanket on a cold night, do you place it loosely over you so that you have lots of air between the blanket and you or do you fit it snugly to minimize the air? So, as with the blanket with the air layer, the thermal inertia plays a role. However, as I tried to say earlier, there is also the fact that the atmosphere has to warm up to a specific temperature–that where the energy under the blackbody curve minus the bites taken out of it by the greenhouse gasses equals energy in. The fact that you have to achieve a finite degree of warming before equilibrium returns means that it will take time to return to equilibrium.

  2. 202
    Ray Ladbury says:

    Clear Thinker, I think that at a minimum an understanding of the basic physics and chemistry of atmospheres is essential–including thermodynamics, physics of fluids, etc.. Beyond this, one has to make an effort to understand the science that specifically applies to the Earth’s climate. I know of very few who have made such an effort and come away with significant doubts that humans are behind the current epoch of climate change. Climate science is complicated. The evidence that humans are behind the current warming is straightforward and pretty difficult to argue with.

  3. 203
    Hank Roberts says:

    > We don’t know exactly which geophysical forces
    > are most important for climate change

    Mr. Clear — note the context — you’re quoting his discussion of the history of this science, of events that moved at a geologically slow pace.

    Don’t confuse yourself — what you quote is not about current events. There he was writing about how we understand paleoclimate, the deep past, including all natural causes moving at natural rates of change.

    Dr. Weart also writes:

    “… well-meaning errors can promote confusion about whether humanity is truly causing global warming by adding carbon dioxide to the atmosphere….

    … These issues were satisfactorily addressed by physicists 50 years ago, and the necessary physics is included in all climate models.”

    http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument/

  4. 204
    Lawrence Brown says:

    Re:184 by Clear Thinker.
    Another helpful discipline in understanding climate change would be a short coursee in electromagnetic radiation, with particular attention to Stefan’s law which quantitatively relates temperature with it’s total radiant energy.

  5. 205
    Mark says:

    Rod B:

    “JPR, to oversimplify the basic absorption physics to maybe clear the stage: …”

    You then proceed to make a MORE COMPLICATED explanation of the physics, not a simplified one. And proceed to make mistakes.

    This works with “the man in the street” but unfortunately scientists know where you make mistakes.

    The specific heat capacity is how much energy you have to put in to make it “move faster”. Even if they are the same weight, a molecule has a higher specific heat capacity because it has more modes to spread the energy over than an atomic gas. So pointing out that the energy intercepted goes to non-velocity energy stores is irrelevant: it’s already taken care of by the specific heat capacity.

    It makes even less difference when it is in a mixed atmosphere or near a surface: a collision with either will or could transfer this energy in rotational movement into the other material.

    You have read but not understood your physics.

    At the best reading of your messages.

    Clear thinker is just trying to “out nice” but is really just trolling.

  6. 206

    Clear Thinker posts:

    Ocean temps. I see suggested experiments that try to show how the oceans
    temp changes. Do these experiments take into account any heat added to the water by underwater volcanic activity or fumeroles or even fresh water runoff?

    I doubt it. They would be trivial in magnitude compared to the heat the oceans absorb from the sun and the atmosphere.

  7. 207
    Ray Ladbury says:

    Mark, Actually, the equation E=CpT only holds for a gas at equilibrium, and when the gas is not in equilibrium with the photon field (e.g. outgoing IR), then it really isn’t quite in equilibrium. What stat mech tells us is that the gas will quickly transition in a direction toward equilibrium (most likely via collisional relaxation), but to do this it must warm up to the point where outgoing IR is again equal to incoming absorbed sunlight.
    In physics, “nonequilibrium” thermodynamics is really “near-equilibrium” thermodynamics, since we really don’t know how to treat systems that are far from equilibrium. Fortunately, the climate system remains near enough to equilibrium (though not quite at equilibrium) that standard methods apply.

  8. 208
    Ray Ladbury says:

    Clear Thinker asks what background one should have to debate climate science.

    Wait a minute. Shouldn’t the answer to this be obvious. I mean if you aren’t publishing on the subject regularly in peer-reviewed journals, your opinion counts for bupkis, because that is where the only scientific debate worthy of the name occurs.

    If a scientist knows all the basic physics and chemistry but is ignorant of the history and development or the most recent developments in the field, he is certainly not qualified to debate with the subject matter experts.

    OTOH, even if one is a “climate expert,” it means little if they are not publishing, since that means:
    1)they aren’t actively following and contributing to the field
    2)that they may be ignorant of recent developments
    3)that their approaches may be infertile or unproductive (i.e. they could be cranks).

    Sorry, Clear Thinker, but the rest of us are not contributing to the debate. We’re only here to learn. And judging by the relative numbers of publications consistent with and questioning the consensus view, the science is certainly settled. What remains unclear is what to do about the implications of the science–and that is politics. We can certainly contribute there, but our contributions are relevant only to the extent that we understand the accepted science.

  9. 209
    Hank Roberts says:

    Barton, I think it’s important to make clear that the heat from within the planet is not ignored. It’s taken into account — it’s a constant over the time spans we’re talking about, part of the background that doesn’t change.

    Aside from events like the Deccan Traps of course, which we’d notice* if such started to happen again and affected surface temperatures.

    Andy Revkin’s sources at dot.earth I linked to above are good on clearing up this “undersea volcano” notion current in the blogs.
    ______________________
    * understatement

  10. 210
    Martin Vermeer says:

    #177 Guenter Hess

    However, as a scientist I would be curious why under LTE, the emission coefficient for a CO2 band can be estimated using Kirchhoff’s law, while the energy transfer is collision dominated.

    At the risk of misreading you, I think you’re making the same mistake as Rod: not seeing the gas for the molecules :-)

    Yes, the energy transfer is collision dominated, but that works both ways. Energy from N2, O2 collisions also excites CO2 molecules into the 15um bending state. The 4% occupation is what you see if you take a snapshot at any given moment. You don’t need to know the details of all the reactions to get this percentage, just temperature and energy level (and the knowledge that it has two degrees of freedom), thanks LTE.

    Emissivity is equal to absorbtivity. The latter is what you see if you send a 15um beam into the gas — it gets fully absorbed after only a few tens of metres — it is opaque at these wavelengths. Such a layer is also a black body for this radiation, it emits according to the Planck curve for its temperature: emissivity is also 100%. The 4% occupancy rate has dropped out by the LTE magic :-)

    Hope this was what you were wondering.

  11. 211
    Mark says:

    Ray, #207.

    Yeah, I know. Though this is mostly ignored in astrophysics because you have to assume an isostatic balance in radiation or your maths on what’s happening a trillion miles away gets very confusing…

    Of course, they may have made some shortcuts available since last I did any study.

  12. 212
    Rod B says:

    I really appreciate everybody’s responses and help ala my concern with why temp lags CO2. Boiling the responses down to the temperature inertia displayed especially by oceans but also to some extent by ground and even the atmosphere itself still leaves some troubling questions in my mind — the process still doesn’t fully explain the actual timing of the delay, nor explain how the temperatures being measured for the graph are overwhelming of lower atmosphere. However, my remaining questions are not as noisy as my observation of “years, decade, decades” of delay. My observation (looking at graphs) can’t really be that precise (I’ve been chastised before for eyeballing instead of doing linear regressions :-) ), especially when the affecting temporal weather-like anamolies are added in. Bottom line, my assertion is more noisy than yourall’s explanation, so I’ll go with what you all say.

    Cleaning up some of the pieces:
    Mark, I’m not sure what got stuck in your craw but energy (radiation) absorption into vibration vs. specific heat is a distinction without a difference. That radiation is absorbed by “(true) internal degrees of freedom”, not translation I think is relevant to JPR’s question. Why you think explaining the reverse molecular energy transfer would make it less complicated totally escapes me. ps. besides, Martin (210) evidently filled in those blanks

    Chris, there are folks that maintain that energy in vibration affects/effects classic thermo temperature. 2nd, Ray is the official poster here to beat me up over my belief that a single molecule manifests temperature. Go find your own battles with me! :-P Finally, complaining over the use of “energy stores” seems a colossal nit-pick (oxymoron??) for an oversimplified description.

    Thanks all.

  13. 213
    Clear Thinker says:

    Barton Paul Levenson Says:
    23 July 2008 at 6:19 AM
    Clear Thinker posts:

    “I doubt it. They would be trivial in magnitude compared to the heat the oceans absorb from the sun and the atmosphere.”

    Mr. Levenson,

    Thank you for the civil response, it’s much more than I’m getting from others. It really is appreciated.

    Here’s why I was asking about the experiment that Chris had suggested on post #196. It seems as if his experiment was only including atmospheric temps and water. Would his experiment not be more conclusive if he had added another heat source/s into the water?

    Do we really know every volcanic action that takes place on any given day? Do we really know how many fumeroles there are and at what rates are they all pumping out heat? Do we take into account all the Nuke plants, or even mulch paper plants, and other industries around the world that are pumping heated water into the Oceans? Do we know how fresh water runoff effects the Oceans temps? Do we know how rain effects the Oceans temps? Do we know how much rain falls into the Oceans? Ditto for land?

    I totally understand that the heat from the Sun and atmosphere are the largest contributors, but there are other sources of heat not accounted for.

    All I was suggesting was, shouldn’t Chris have added more variables to his experiment?

    Once again, thank you for being civil.

  14. 214
    Guenter Hess says:

    #210 Mark,
    thanks for your reply and interesting comment.
    Actually you describe what I am wondering about.
    I read your argument before, and I understand the reasoning via the Einstein coefficients, assuming thermodynamic equiilibrium and calculating finally the source function as being equal to the Planck function from a mathematical point of view. The same can be done including collisions.
    My problem is that I feel that this line of reasoning is contradicted by the LTE assumption itself.
    Lets for example compare two identical slabs of air containing CO2, one is heated by an hypothetical infrared laser at the CO2 bending mode and the other one via collisions by a hypothetical reservoir containing Oxygen and Nitrogen.
    Both slabs are finally brought to the same LTE state characterized by the same temperature and Maxwell Boltzmann distribution via collision. Pursuing the argument above, both states should have the same emission characteristics. But this in turn should mean that a LTE state emits in any case out of the 4% concentration of the vibrationally excited molecules.
    However the average kinetic energy of a nitrogen or oxygen molecule does not allow the excitation of a CO2 bending mode beyond Maxwell Boltzmann distribution, otherwise I think you would violate the 2nd law of thermodynamics.

  15. 215
    Hank Roberts says:

    Mr. Clear, you miss the point

    You’re listing things that — in the last century or two — haven’t changed so the difference they make in the year to year temperature hasn’t changed.

    Spencer Weart, as quoted before:
    ————-
    “… well-meaning errors can promote confusion about whether humanity is truly causing global warming by adding carbon dioxide to the atmosphere….”
    ————-

    I’m sure you mean well, because you’re so polite.

    But you’re not thinking. You say there’s an effect so there might be some hidden cause.

    Nope, you need _two_ hidden causes, one to counteract the known forcings that do work in the models, then another hidden one to make up the difference so the models still work. You need a hidden cold source and a hidden hot source, neither detectable by scientific work so far.

    To explain a change, you need to observe a change.

    If there were more heat than usual being added at the bottom of the ocean, it would show up in the deep ocean temperatures.

    If there were a source of hot water running off from a nuclear power plant big enough to explain the sea surface temperature, it would show up as a hot spot on the sea surface.

    There might be some incredibly powerful forcing hidden somewhere in some corner of the globe contributing enough to make the global average change but not showing up as a point or small source? Nope.

    Nature has gone on as it did before; human activity is what’s changed dramatically and far faster than natural rates of change

  16. 216
    Rod B says:

    Guenter (214), I’m not sure if my tentative answer is even close to what you’re asking… I’ll try and you or others can correct me. The 4% population of the vibration energy level is a quantum mechanical Boltzmann factor probability that is based on LTE and is just dividing up all the energy in the molecules accordingly based mostly on the background (spam filter doesn’t like “amb***nt”) temperature — roughly the vibration energy level over kT as a power of e. Radiation is absorbed into the 15um vibration band separate, over and above, and irrespective of the 4%. Vibration-rotation are the only internal energies that can absorb radiation. They will absorb, based on somewhat different quantum mechanic parameters, even if the 4% is the current nominal population. Absorbing the radiation will put the molecules temporarily out of LTE. Then, to use precise physics terminology, they’ll get very antsy and want to unload their off-balance situation. Eventually the absorbed energy gets distributed via collisions amongst the molecules (or emitted) and they’ll be back in LTE.

    I think if LTE and the 4% exists there is still a quantum mechanical probability that a CO2 will spontaneously emit. Also, I think a N2/O2 collision with CO2 can transfer energy from translation to CO2′s vibration — not as likely if LTE exists, but a long ways from impossible or prohibited. I’m not 100% certain of these, however, so others ought to comment.

  17. 217
    Ray Ladbury says:

    Clear Thinker, your query about volcanic eruptions is telling of the differences between scientific and nonscientific educations. A scientist would look at the energy of a typical eruption and compared it to other energy sources in the problem. When you do, you find that volcanism is trivial compared to insolation. The thing is that a layman looks at a volcano and sees a “big” event. However, that event is short-lived and localized, so it does not contribute nearly as much energy as a global source like insolation or the greenhouse effect.
    Likewise, if one hasn’t been paying attention to the latest research in climate science (or any other field), one is prone to rehash settled arguments, reinvent wheels and make other elementary blunders that a true expert would avoid. There is no substitute for long experience coupled with concerted, prolonged effort in science.

  18. 218
    Clear Thinker says:

    Mr. Roberts,

    You wrote: “You say there’s an effect so there might be some hidden cause.”

    No, no, not at all, I was merely asking if all the info pertinent for Chris’s experiment was being included. When a scientist performs an experiment, or even a laymen, it always seems to come down to what may have been missed. I don’t need to tell anyone here that modeling climate is a daunting task.

    There are things we are missing. For instance… Can anyone here tell me how much precipitation falls on the Earth and how that affects global temperatures? And how do clouds affect global temps?

    Nothing “hidden” just not included for whatever reason.

    Thanks you for being so reasonable.

    [Response: Precip ~ 3mm/day globally w/ about -1 W/m2 surface energy flux, cloud radiative forcing ~ -48 (W/m2 Short wave), 31 (W/m2) long wave) (globally). Both effects 'included'. - gavin ]

  19. 219
    Rod B says:

    Hank (215, so far), just a quick curiosity question. Even if there were those ocean heat sources, wouldn’t the cooling from the heat of fusion through evaporation overwhelm them?

  20. 220
    Hank Roberts says:

    PS, this is worth reading. Note, not while drinking coffee: http://timlambert.org/2004/12/hissink/

  21. 221
    A.C. says:

    decidedly OT, but perhaps noteworthy:
    http://junkraft.blogspot.com/

    tells the story of Dr. Marcus Eriksen and Joel Paschal, sailing across the ocean on what amounts to a pile of (recyclable) trash.

  22. 222
    Marcus says:

    #213, #215: Just an observation to add because of the comments of “nuke plants and other industries adding heat to the system”: there was a recent edition of EOS (the AGU journal) that had a paper looking at the heat released by theoretical increases in human activity. The paper assumed: a) that we switched to zero-GHG power. b) that the zero-GHG power was in large part nuclear, coal with CCS, solar beamed from satellites, etc., and c) that energy use continued to increase at 1% or 2% per year.

    Eventually (2300 or so) the direct heat produced by energy use is sufficient to increase global temperatures by a couple degrees C, even without GHGs. But that’s quite a number of doublings away.

    So, yeah, at the moment heat from human activity is at least two orders of magnitude less than the heat that is caused by GHG release from that activity (I’ve done a back-of-the-envelope calculation that shows that 1 MMBtu of coal burned leads to about 280 times as much lifetime total atmospheric warming directly due to radiative effects of the released carbon dioxide). So we can safely ignore human heat sources on the global scale.

    Similarly, my understanding is that average global heat flow from all geothermal sources is more than an order of magnitude less than the direct heat flow caused by anthropogenic GHGs, and presumably the fluctuations in that source are smaller yet, so we can mostly ignore geothermal too (at least for global scale analysis. If we care about the heat in one specific spot that happens to be near a fumerole, then we need to add it in).

  23. 223
    Mark says:

    Guenter Hess Says #214 I think you meant Martin.

    Remember that the energy is the average. So some will collide with enough energy compared to the thing it’s hitting to move it out of any vibrational, torsional or rotational mode. It could extract the vibrational, torsional or rotational energy in the other collision (think putting spin on the cue ball putting spin on the coloured ball). If the energy quotient of the average molecule in the atmosphere is not enough to keep these states filled according to the relevant laws, then these over-excited (by laser or whatever) states will release their energy into the medium.

    The only places it won’t is when you are in an optically (at the relevant frequencies) translucent medium. In which case, the IR excitation energy is as likely to go out without being absorbed as it is to not thermalise.

    So speculations on a medium only a few optical depths deep isn’t really applicable: you aren’t holding on to much of the energy being pumped in anyway, so your query doesn’t hold.

    When it comes to the parameterization of transmission and absorption, there are spec ialists (without the space, this is a spam word!) who work at the quantum level. Not so much to parameterize the fluxes but to actually work out what the space satellites are telling you. After all, all you get from a satellite is not a temperature profile, but the IR intensity of a bandpass receiver of varying effectiveness along a small solid angle at one specific time. Working out what THAT means wrt temperatures is NOT for the faint hearted.

    I wouldn’t even try.

    But you could try finding one of them and asking them.

  24. 224
    Tank Dobermann says:

    This site has been infiltrated by a number of conservative NewsBusters poster/trolls- ClearThinker, PopTech, and Danbo. They were dispatched to this site by the Associate Editor of Newsbusters, Noel Sheppard. Their primary mission was to engage the honest climatologists of this site into a twisted discussion in order to get banned or deleted. In doing so, they copy what comments are deleted and post them on the NB site to show how scientists censor a “true” debate. My suggestion is to ignore and disengage from any discussion with these three individuals. They are quote miners and will try to use your words against others. It’s infantile and to be expected by a radical right wing group who’s primary mission is to expose and combat liberal media bias. The Associate Editor of NewsBusters will not engage in a scientific debate on Global warming since he lacks the intelligence and intellect to discuss and understand basic chemistry and physics. He’s an economist with no scientific background. I must commend all of you on your eloquent and articulate discussions with these trolls.

    [Response: I am aware of such things. But the bottom line is that we are happy to answer questions that, while they may be disingenuous, might be of interest to others. As long as posters are polite and not too far off topic or repetitive, they are welcome to stay. Who knows, maybe they'll learn something... - gavin]

  25. 225
    Tank Dobermann says:

    We can only hope, Gavin. Thanks for the response. This site is one of the best I’ve seen. Good work! Looking forward to learning more everyday!

  26. 226
    paulm says:

    There are definitely ‘professional’ posters planted by whoever everywhere. They especially like to lurk in popular sites, like accuWeather.com, where they pounce on any topics which are on the edge like :
    http://global-warming.accuweather.com/2008/07/gore_offers_a_challenge_1.html

    and
    http://global-warming.accuweather.com/2008/07/cdc_testimony_was_edited_by_vp.html

    They flood the first entries and then the last ones in a manipulative manner.

  27. 227
    Poptech says:

    Why are you afraid of my questions Gavin? You are the “expert”.

    [Response: Repeating myself over and again when it's clear you haven't the foggiest (smoggiest?) idea about what you are talking about is quite dull. You need to come up with something a little more challenging. Now run along and tell the other children how mean I am. - gavin]

  28. 228
    Hank Roberts says:

    Rod, sorry, I haven’t a clue what you mean in 23 July 2008 at 5:34 PM — do you mean volcanic events change aerosols by turning water into water vapor that condenses out later? Sure.

  29. 229
    Ray Ladbury says:

    Clear Thinker, an anecdote to illustrate a bit about the education of a scientist. When I was but a wee graduate student in physics, we were all required to take written and oral exams to be admitted to candidacy for the PhD. The written exams were (mostly) material we had had in classes, but the oral exams could cover ANY topic. Once a grad student was facing 3 hostile faculty members, and one of the faculty picked up a phonebook and began perusing it as he was fumbling with a problem. Once the student finished, the prof asked: “OK, how many piano tuners are listed in the phone directory for the greater metro area…and you’d better be right within 10 %?” Scientists have to KNOW things. They have to KNOW how things fit in with everything else. And if they don’t know, they have to figure out ways of learning/measuring it. And they’ve been learning and measuring things related to climate for over 150 years. So, as you can see, we amateurs (and yes, despite a PhD in physics, I am an amateur here) have a lot to learn here.

  30. 230
    Clear Thinker says:

    Mr. Roberts,

    Thank you for that link in #220. I may or may not agree with the conclusions but it’s just another example of why I think the debate rages on. Which I think is the prudent thing.

    On to other business…
    I got sidetracked from my original question concerning what fields of Science would someone need to be proficient in, in order to debate AGW. The feedback was some of what I expected and some I did not. But I do appreciate those that took my question seriously. I have been upfront and very honest about where I stand on this issue so hopefully you understand by now that I have nothing up my sleeve. May we all learn from each other.

    Back to why I asked the question of education level. I have been interested in the AGW argument for a very long time and have read many facts, opinions, articles, reviews, journals, etc, from people in the following fields… Physical Chemistry, Geophysical Science, Agricultural Biology, Hydrogeology and Engineering Geology, Geology, M.Eng., P.Eng, Earth Sciences, Atmospheric Science, Advanced Physics, Chemistry, Molecular GeneticsPhysics, Theoretical Chemistry, American Association of State Climatologists, Sedimentology,vBioChemistry, Electrical and Mechanical Engineering, Environmental Science, Applied Mathematics, Agronomy, Mathematical Ecology, Wildlife Biology, Animal Ecology in Arctic and Subarctic Regions, Mathematical Logic, Meteorology, Climatology, Chemical Engineering, Solar Physicist and Climatologist, Mathematical Statistics, Earth Sciences, Geophysics, Marine Biology, Microbiology, Micropalentologist, Paleoclimatologist, Isotope and Planetary Geology, Analytical Chemist, Particle Physicist, Organic Chemistry, Botany, Nuclear Physics, Zoology, Astrophysicist,
    Biomolecular Engineering, Palegeophysics, Medical Entomology, Forest Biology, and Aeronautics.

    The only sure thing I have found to date by reading and/or listening to these experts is that there are still those that question if AGW is caused by “A”. Don’t be alarmed, I know there are others in the very same fields as those above that say different. One odd point of contention for me is the notion that unless your papers are peer reviewed that your papers should be ignored. Don’t get me wrong, I know how important the process is and why it’s done, but many a Scientist in the past that were reviewed and subsequently scoffed at by their peers turned out to be on target.

    With this in mind, should a person, Scientist or not, really ignore an expert when they use 30 different equations to disprove a model (yes, I know you know whom I’m refering to)?

    [Response: Please. He's no expert, and he used one equation (rewritten 30 times) (incorrectly to boot). I'll post some more on that later. - gavin]

    I know this was long and arduous, but so is the AGW issue. Thank you for your patience.

  31. 231
    Poptech says:

    Gavin, you have yet to prove where Mr. Sheppard equated Aerosols with Smog by quoting what he said. You stating this as such without the quote does not prove anything and it appears you are making this up.

    Just an FYI fog can also be a part of smog by definition.

    [Response: Hmmm.... so let's see. Perhaps Sheppard's use of the term "chicken and egg conundrum" is unfamiliar to you? It refers to something (X) causing something else (Y) which goes on to cause X over again. What are the somethings to which Sheppard refers?

    In an interesting chicken and the egg conundrum, scientists in America claimed Thursday that global warming causes smog.
    So, cleaning the air causes global warming -- which ends up leading to higher levels of smog?

    It's pretty clear from this sentence that Y="global warming". X is first "clearing the air" (referring to the reports on the GRL aerosols paper), and yet at the end, X is clearly 'smog' (referring to the press about the EPA ozone report). So if Sheppard is not equating the two, perhaps you would care to explain what is chicken and what is egg? It can't be aerosols, because the EPA report does not suggest the warming increases aerosols. And it can't be ozone because ozone is a greenhouse gas and clearing it from the air would lead to a cooling not a warming. Do please enlighten me. - gavin]

  32. 232
    Hank Roberts says:

    You might want to check your other references first.

    I think you’ve misunderstood what you already read.

    Peer review doesn’t assure that a paper will be paid attention. It’s the first step, only.

    Recall you were quoting earlier from Spencer Weart? You read the answer to your question right there, on the web page you quoted from.

    “The scientific literature. … the thousands of scientific papers scattered like seeds in the past, we are naturally most interested in those that have borne fruit.”

    You might also find this helpful — I certainly have, face to face, since before the old Usenet days, on websites, any place I might ask scientists amateur questions. It really helps to follow his advice. Show you’ve read something and understood some of it and then ask a question that shows you can learn. It really encourages good answers:

    How To Ask Questions The Smart Way
    Eric Steven Raymond.
    http://www.catb.org/~esr/faqs/smart-questions.html

    Especially his last point about how to answer well.

    But I digress, sorry. The topic deserves better focus.

  33. 233

    Re. #224 Tank Dobermann

    They may be reposting what is getting deleted over on the NB site, but they can’t claim that RC is censoring the scientific debate. They are censoring the irrelevant noise that is out of context and also repetitive points and the argumentum ad hominem.

    Example: Gavin edited two of my posts in this thread:

    #101 and #181

    My fault of course. I went to far away from the relevant points.

    But NB can’t claim bias in the scientific realm. I support Gavin and the RC team entirely in their moderation in order to keep the conversation relevant.

  34. 234
    Ray Ladbury says:

    Clear Thinker, I’ve said this before. Your “experts” count for nothing unless they are actively publishing in climate science. It is a one thing to be able to learn from and assimilate the research of others. It is a very different thing to actively contribute to a field of study. The latter are the people who count. The rest are welcome to come here and LEARN from those experts. Or do you think that you can do intellectual battle with Stephen Hawking just because you’ve read his “A Brief History of Time”?

  35. 235

    #230 Clear Thinker

    Peer review is only part of the process. There is also peer response. Those that survive peer response become accepted or argued further to refine the understanding. Those that don’t become less relevant or irrelevant.

    http://www.realclimate.org/index.php/archives/2005/01/peer-review-a-necessary-but-not-sufficient-condition/

    http://www.realclimate.org/index.php/archives/2008/04/blogs-and-peer-review

    Then there is relevance and context.

    For example: If you look at certain charts and graphs that are used to prove global warming is not human caused and compare them to actual nasa data, you can spot the obvious errors.

    http://www.uscentrist.org/about/issues/environment/john_coleman

    If you search the page for “Historically we can clearly see that hydrocarbon use does not correlate with temperature changes.” you will find the chart I am referring to.

    This chart has more than one problem. I will only illuminate one of them and compare it to NASA for you.

    The chart displayed shows that TSI is around 1372 W/m2 from the satellite data outside of the atmosphere. Whomever made the chart made a fairly major mistake. If the maker of the chart is referring to any actual satellite data it is likely the Nimbus7/ERB data, not the current corrected modeled data that NASA accepts as the best representation.

    Now here is NASA’s satellite data for TSI graphed:

    http://earthobservatory.nasa.gov/Study/VariableSun/variable2.html

    If you look at the second chart on the page that shows all the different satellite measurements you can see that the only one that is close to 1372 W/m2 is the Nimbus7/ERB

    Now scroll back up on the NASA page and you can see the corrected data set from the composite readings.

    That is the accepted data based on the corrections. That indicates the TSI is around 1366.5 to 1367 W/m2

    The point is, some people are using incorrect data and representing it as actual. To believe the other chart, which is based on limited data, uncorrected; we have to accept that NASA is wrong. You merely have to decide if you ‘believe’ the incorrect data is true, or the updated corrected data from NASA.

    In other words, it’s not about belief. It’s about the real data, the relevant data, the relevant context and the relevant understanding.

  36. 236
    Poptech says:

    What is pretty clear is that no where did Mr. Sheppard substitute the word ‘Aerosols’ for the word ‘Smog’ as your implication. In that sentence he uses the word ‘smog’ not ‘photochemical smog’. The definition of smog allows for it’s usage in that sentence and in that context, even in reference to aerosols and smog. You added in the word ‘photochemical’.

    [Response: Ozone is the prime constituent of photochemical smog. The EPA report (which Sheppard did not read) was about ozone. Therefore the use of the word 'smog' by Reuters when discussing the EPA report referred to photochemical smog. If Sheppard knew what he was talking about, then his confusion would not have arisen. Like I said before - it always pays to read the real sources - not just the media reports. Bored now. - gavin]

  37. 237
    Joel Black says:

    I’m surprised that none of the regular contributors here mentioned to Mr. Clearthinker that experts in statistics should also be consulted. Or did I miss that?

  38. 238

    Okay people, this issue needs to be looked at here: http://www.theaustralian.news.com.au/story/0,,24036736-17803,00.html

    [Response: See above - gavin]

  39. 239
    Hank Roberts says:

    Taking (or attempting) to take the thread back to the topic — aerosols chemistry and climate — might help clarify that there’s not just one species of chicken and one sort of egg involved. That’s a common error, oversimplifying.

    Look back at the thread.
    Kinds of aerosols
    How they are produced
    What they’re like at first
    How they change over
    over time
    depending on what else is around
    in different parts of the atmosphere
    with different amounts of sunlight
    with different amounts of ultraviolet.

    Coal isn’t pure carbon, so you don’t even start with one ancestral dinosaur form — there’s a flock of different stuff in the fuel.
    Burn those, with changes during and after combustion.

    Result? Not simple.

    One surprise I recall from a few years ago — think about Dickens and Conan Doyle’s descriptions of coal smoke fogs, then look at the writing Google Scholar turns up:

    http://books.google.com/books?id=7OWtDwfCHgcC&pg=RA1-PA339&dq=coal+smoke+fog

    http://books.google.com/books?id=P3kCAAAAIAAJ&pg=RA1-PA383&dq=coal+smoke+fog

    http://books.google.com/books?id=ybsOAAAAIAAJ&pg=PA19&dq=coal+smoke+fog

    http://books.google.com/books?id=ZRIAAAAAMAAJ&pg=RA1-PA286&dq=coal+smoke+fog

    Compare this to more recent descriptions — very different behavior.
    I recall the latitude makes an important difference in the photochemistry.

    http://scholar.google.com/scholar?hl=en&lr=&q=+Beijing+India+brown+cloud+air+quality+latitude+photochemistry&btnG=Search

    I don’t want to sidetrack the thread from discussing current science (it’s hard not to be distracted by, well, tasty distractions, but let’s not).

    So to try to ask a useful question — has anyone a good cite to any compilation or review article comparing the first great historical era of coal burning to the current one? The bits I link above got me started but if someone knows where it’s been pulled together I’d love to understand better why the two times were so different on the ground.

    (Not asking for an immediate answer or attention, just putting the question out here for whenever someone happens in with a pointer.)

  40. 240
    Clear Thinker says:

    One Salient Oversight Says:
    23 July 2008 at 9:58 PM

    On sites where I am not well known, I normally address people with either Mrs. or Mr. because it’s the civil thing to do. The name you use makes it difficult to use either so is it ok to address you as OSO?

    To your link… I brought this up I think yesterday and it was immediately dismissed by Mr. Schmidt. Think what you want about it but it has caused quite a buzz. Some of which is very ugly.

    Thank you for posting it again. Any and all relevant info should be considered if we are to get to the truth. Whether we like it or not.

  41. 241
    Chuck Booth says:

    Re # 240 Clear Thinker:

    I normally address people with either Mrs. or Mr. because it’s the civil thing to do.

    The respectful way to address a scientist with a Ph.D. who occupies a position of authority, as do the RC moderators, would be “Dr.”, as in Dr. Schmidt.

  42. 242
    Guenter Hess says:

    #216 RodB,
    Yes, I agree to all you said.
    My question really is:
    1. about the magnitude of the emission coefficient for a slab of atmosphere containing CO2 under LTE conditions (which is valid below 75 km) compared to a non-LTE situation (which holds above 75 km).
    2. about the calculation of the source functions for radiative transfer under LTE conditions.

    I think that the detailed answer will not change anything about average warming, however it would fill my curiosity. Also I think the correct answer will cover some skeptical arguments distributed within the Internet. I tried to ask some of the experts mentioned on Realclimate directly, but didn’t get an answer yet.

  43. 243
    Guenter Hess says:

    #223 Mark
    Yes I meant Martin. But thanks for your answer.

  44. 244
    Hank Roberts says:

    Chuckle.
    Sal (may I call you Sal?), I think you nailed that one on your own page.

  45. 245
    dhogaza says:

    To your link… I brought this up I think yesterday and it was immediately dismissed by Mr. Schmidt. Think what you want about it but it has caused quite a buzz. Some of which is very ugly.

    Yes, very ugly. Monckton’s claiming to have published a “major peer-reviewed paper in an APS Journal”, for instance, is a very, very ugly lie. One which I suspect Clear Thinker and friends happily embrace.

  46. 246
    Figen Mekik says:

    Chuck,

    I was biting my tongue not to say what you brought up about Mr. vs. Dr. Schmidt. I am glad you said it so eloquently. Even PhD bearing scientists call each other Dr. So-and-So if they do not know each other well or one wants to show deference to the other for his/her extensive contributions to the field (like the RC moderators). Or they go by first name, like the RC moderators like to do here. But somehow Mr. or Mrs. just doesn’t sound so good :) I don’t mind when my students (undergraduates) call me by my first name (I encourage it) but Ms. Mekik kills me, especially since male professors tend to be addressed by the students as Dr. or Prof more frequently. But that’s another story, but female profs get the Ms. or worse Mrs. :)

  47. 247
    Geoff Wexler says:

    Qualifications and prejudice.

    Several people have discussed what qualifications you need to have a useful opinion about a branch of science. Having set up a set of imaginary guidelines there will always be people who will slip through the net. That is because of prejudice, which is a common human quality. Imagine a good scientist who reads a paper early on in his career which relies on computer simulations and he can see that it has some weaknesses. As a result of this experience he generalises. To save time, he stops reading all such papers. He fails to see the progress in the subject, becomes out of touch but does not realise it. Is such a scientist well qualified? This is of course a hypothetical example and I admit that I myself have a similar prejudice when it comes to economic models. But I would not expect anybody to pay much attention to what I have to say on that topic.

    This process of generalisation also applies to the work of individuals. Although I am not a climatologist I have enough understanding to read the ‘very simple’ so called papers of the amateur mentioned in another thread. It involved some time, because of the deliberate mystification which it used to veil unjustified assumptions or inconsistencies. I have therefore decided not to plough through the detail of any more such papers. Perhaps one day this person will make a breakthrough and I will miss it? Generalising about a person involves a slight risk, but doing the same thing about a whole subject is only justifiable if you are prepared to keep quiet.

  48. 248
    Martin Vermeer says:

    Rod B #216: yes Rod, good summary. You’re getting there.

    I think if LTE and the 4% exists there is still a quantum mechanical probability that a CO2 will spontaneously emit. Also, I think a N2/O2 collision with CO2 can transfer energy from translation to CO2’s vibration — not as likely if LTE exists, but a long ways from impossible or prohibited. I’m not 100% certain of these, however, so others ought to comment.

    Those probabilities not only exist, but are substantial. E.g., the transfer between vibrational and translational energy has the same probability in either direction (but finding an N2 with the necessary high translational energy may be a bit harder depending on temperature, courtesy Maxwell-Bolzmann). Also the probability of emission by CO2 is related to that of absorption, but here, the Planck function is in-between because the reaction involves photons.

    Without these relationships (which are based on time reversion symmetry) thermodynamics wouldn’t be what it is :-)

  49. 249
    Joseph O'Sullivan says:

    Mr Clear Thinking

    If you want to debate the science the critical thing is to understand what science is and how it works. The level or area of education is not nearly as important. Science is a process that investigates the physical world to learn about the physical world around us. The community of scientists has an established process to do this.

    The most important aspects of this process:
    Physical data is the basis for everything
    Its very thorough and detail oriented
    The standard of proof is high

    If an idea goes through this process and withstands the harsh spotlight of the scientific community it meets the basic test for reliability. The essential part of this process is peer-reviewed scientific publication. If an idea does not go through this process there is no guarantee that it is based on physical facts. If an idea is not based on physical facts it is not science.

    If someone wants to question the science they should do it with science. If people clearly think the implications of the science are inconvenient, they should make it clear that is what they are thinking. Anything else is an end-run around the processes that make science reliable. Trying to compare data, analysis and experimentation with op-eds, hand-waving and using quotes in a misleading way is dishonesty Mr Clear Thinking.

    An analogy I have heard that applies is people can endlessly debate if a glass is half-full or half-empty, but scientists would never. Scientists would tell you that there is a 500ml container and in it is 250ml of liquid H2O with trace amounts of minerals and atmospheric gases mixed in. If that is good or bad is not a question scientists can answer.

  50. 250

    Clear Thinker posts:

    Do we really know every volcanic action that takes place on any given day?

    Probably not, but we have good estimates for the total over a given period of time.

    Do we really know how many fumeroles there are and at what rates are they all pumping out heat?

    Do we take into account all the Nuke plants, or even mulch paper plants, and other industries around the world that are pumping heated water into the Oceans?

    I assume we do. If you’re really interested in the answer, why not find some estimates and work out the magnitude of the effect yourself?

    Do we know how fresh water runoff effects the Oceans temps?

    I think it would be trivial, but feel free to prove me wrong by doing the calculation.

    Do we know how rain effects the Oceans temps?

    See above. If it helps, the amount of water vapor in the air at any given time is about 1.27 x 1016 kilograms. The mass of the oceans is about 1.39 x 1024 kilograms. What does the ratio tell you?

    Do we know how much rain falls into the Oceans? Ditto for land?

    Yes, good estimates for those figures have been available for a long time. If you can find a copy of the paper by Walker, Hays and Kasting (1981) on the silicate-carbonate feedback, it puts a lot of those figures together. It used to be available on the web for free but is now behind a paywall. But you may be able to find it at a university library somewhere.

    I totally understand that the heat from the Sun and atmosphere are the largest contributors, but there are other sources of heat not accounted for.

    All I was suggesting was, shouldn’t Chris have added more variables to his experiment?

    If the relative magnitude of the other sources is small enough, they can be ignored without much changing the results.


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