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Simple Question, Simple Answer… Not

Filed under: — group @ 8 September 2008 - (Français) (Japanese) (Finnish) (Czech)

Guest commentary by Spencer R. Weart, American Institute of Physics

I often get emails from scientifically trained people who are looking for a straightforward calculation of the global warming that greenhouse gas emissions will bring. What are the physics equations and data on gases that predict just how far the temperature will rise? A natural question, when public expositions of the greenhouse effect usually present it as a matter of elementary physics. These people, typically senior engineers, get suspicious when experts seem to evade their question. Some try to work out the answer themselves (Lord Monckton for example) and complain that the experts dismiss their beautiful logic.

The engineers’ demand that the case for dangerous global warming be proved with a page or so of equations does sound reasonable, and it has a long history. The history reveals how the nature of the climate system inevitably betrays a lover of simple answers.

The simplest approach to calculating the Earth’s surface temperature would be to treat the atmosphere as a single uniform slab, like a pane of glass suspended above the surface (much as we see in elementary explanations of the “greenhouse” effect). But the equations do not yield a number for global warming that is even remotely plausible. You can’t work with an average, squashing together the way heat radiation goes through the dense, warm, humid lower atmosphere with the way it goes through the thin, cold, dry upper atmosphere. Already in the 19th century, physicists moved on to a “one-dimensional” model. That is, they pretended that the atmosphere was the same everywhere around the planet, and studied how radiation was transmitted or absorbed as it went up or down through a column of air stretching from ground level to the top of the atmosphere. This is the study of “radiative transfer,” an elegant and difficult branch of theory. You would figure how sunlight passed through each layer of the atmosphere to the surface, and how the heat energy that was radiated back up from the surface heated up each layer, and was shuttled back and forth among the layers, or escaped into space.

When students learn physics, they are taught about many simple systems that bow to the power of a few laws, yielding wonderfully precise answers: a page or so of equations and you’re done. Teachers rarely point out that these systems are plucked from a far larger set of systems that are mostly nowhere near so tractable. The one-dimensional atmospheric model can’t be solved with a page of mathematics. You have to divide the column of air into a set of levels, get out your pencil or computer, and calculate what happens at each level. Worse, carbon dioxide and water vapor (the two main greenhouse gases) absorb and scatter differently at different wavelengths. So you have to make the same long set of calculations repeatedly, once for each section of the radiation spectrum.

It was not until the 1950s that scientists had both good data on the absorption of infrared radiation, and digital computers that could speed through the multitudinous calculations. Gilbert N. Plass used the data and computers to demonstrate that adding carbon dioxide to a column of air would raise the surface temperature. But nobody believed the precise number he calculated (2.5ºC of warming if the level of CO2 doubled). Critics pointed out that he had ignored a number of crucial effects. First of all, if global temperature started to rise, the atmosphere would contain more water vapor. Its own greenhouse effect would make for more warming. On the other hand, with more water vapor wouldn’t there be more clouds? And wouldn’t those shade the planet and make for less warming? Neither Plass nor anyone before him had tried to calculate changes in cloudiness. (For details and references see this history site.)

Fritz Möller followed up with a pioneering computation that took into account the increase of absolute humidity with temperature. Oops… his results showed a monstrous feedback. As the humidity rose, the water vapor would add its greenhouse effect, and the temperature might soar. The model could give an almost arbitrarily high temperature! This weird result stimulated Syukuro Manabe to develop a more realistic one-dimensional model. He included in his column of air the way convective updrafts carry heat up from the surface, a basic process that nearly every earlier calculation had failed to take into account. It was no wonder Möller’s surface had heated up without limit: his model had not used the fact that hot air would rise. Manabe also worked up a rough calculation for the effects of clouds. By 1967, in collaboration with Richard Wetherald, he was ready to see what might result from raising the level of CO2. Their model predicted that if the amount of CO2 doubled, global temperature would rise roughly two degrees C. This was probably the first paper to convince many scientists that they needed to think seriously about greenhouse warming. The computation was, so to speak, a “proof of principle.”

But it would do little good to present a copy of the Manabe-Wetherald paper to a senior engineer who demands a proof that global warming is a problem. The paper gives only a sketch of complex and lengthy computations that take place, so to speak, offstage. And nobody at the time or since would trust the paper’s numbers as a precise prediction. There were still too many important factors that the model did not include. For example, it was only in the 1970s that scientists realized they had to take into account how smoke, dust and other aerosols from human activity interact with radiation, and how the aerosols affect cloudiness as well. And so on and so forth.

The greenhouse problem was not the first time climatologists hit this wall. Consider, for example, attempts to calculate the trade winds, a simple and important feature of the atmosphere. For generations, theorists wrote down the basic equations for fluid flow and heat transfer on the surface of a rotating sphere, aiming to produce a precise description of our planet’s structure of convective cells and winds in a few lines of equations… or a few pages… or a few dozen pages. They always failed. It was only with the advent of powerful digital computers in the 1960s that people were able to solve the problem through millions of numerical computations. If someone asks for an “explanation” of the trade winds, we can wave our hands and talk about tropical heating, the rotation of the earth and baroclinic instability. But if we are pressed for details with actual numbers, we can do no more than dump a truckload of printouts showing all the arithmetic computations.

I’m not saying we don’t understand the greenhouse effect. We understand the basic physics just fine, and can explain it in a minute to a curious non-scientist. (Like this: greenhouse gases let sunlight through to the Earth’s surface, which gets warm; the surface sends infrared radiation back up, which is absorbed by the gases at various levels and warms up the air; the air radiates some of this energy back to the surface, keeping it warmer than it would be without the gases.) For a scientist, you can give a technical explanation in a few paragraphs. But if you want to get reliable numbers – if you want to know whether raising the level of greenhouse gases will bring a trivial warming or a catastrophe – you have to figure in humidity, convection, aerosol pollution, and a pile of other features of the climate system, all fitted together in lengthy computer runs.

Physics is rich in phenomena that are simple in appearance but cannot be calculated in simple terms. Global warming is like that. People may yearn for a short, clear way to predict how much warming we are likely to face. Alas, no such simple calculation exists. The actual temperature rise is an emergent property resulting from interactions among hundreds of factors. People who refuse to acknowledge that complexity should not be surprised when their demands for an easy calculation go unanswered.


623 Responses to “Simple Question, Simple Answer… Not”

  1. 401
    sidd says:

    Steve Reynolds wrote on 17th September 2008 at 2:11 PM

    “You are disagreeing with the consensus of peer reviewed professionals (economists)…”

    these would be who?
    not the same ones who are currently overseeing the meltdown ?
    or…

  2. 402
    Mark says:

    Steve Reynolds, #396

    You are in error. Most anti-AGW economists alarm people like you with that statement.

    The Stern report shows differently.

    And in case you decide that report is partisan, there have been no economists taking up where it gets it wrong.

  3. 403
    CobblyWorlds says:

    #395 Richard C,

    On feedbacks and ice sheets – yes the ice sheets that played a role in the climate response to the rise out of the last glacial minimum are not a factor now.

    However sensitivity is stated in degC / Watt per square metre. So the absence of ice-sheets, another forcing such as CO2 still has a temperature change impact related to it’s atmospheric concentration.

    The issue of risks like ocean CO2 outgassing or clathrate/permafrost CH4 outgassing does not imply a higher climate sensitivity. In leading to more CO2/CH4 in the atmosphere those factors would not imply a higher temperature rise for a specified forcing increase due to CO2/CH4. They would make impacts more serious of an because unforseen increase in atmospheric concentration of CO2/CH4 (hence higher temperatures and more impacts), but the sensitivity would remain the same.

    Mugwump,

    If we follow your counsel then by the time we find out the situation is serious, it will be very probably be too late to avoid dangerous impacts. Even if at such a realisation we stopped all emissions we’d still be a way off equilibrium. You may be happy with the equivalent of driving a car with an increasing time-lag between the controls and the affect on the car. I for one am not.

    Also you claim “bad consequences of climate change are probably a very long way off” whilst at the same time stressing the uncertainty that means we need do nothing. It seems to me your measures of probability are so subjective that they, along with your counsel, aren’t worth bothering with.

  4. 404
    CL says:

    “…the planet is facing a growing environmental crisis, caused largely by climate change, Fingar said. By 2025, droughts, food shortages and scarcity of fresh water will plague large swaths of the globe, from northern China to the Horn of Africa.

    For poorer countries, climate change “could be the straw that breaks the camel’s back,” Fingar said, while the United States will face “Dust Bowl” conditions in the parched Southwest. He said U.S. intelligence agencies accepted the consensual scientific view of global warming, including the conclusion that it is too late to avert significant disruption over the next two decades. The conclusions are in line with an intelligence assessment produced this summer that characterized global warming as a serious security threat for the coming decades.”

    http://www.washingtonpost.com/wp-dyn/content/article/2008/09/09/AR2008090903302.html

  5. 405

    mugwump writes:

    bad consequences of climate change are probably a very long way off,

    The Australians don’t think so.

  6. 406
    dagobert says:

    “The three power systems combine, without batteries, for perhaps 150mpg in a full-size vehicle that can go from 0-60mph in 4 seconds. … Anyone here see a flaw?”

    Yes. 150mpg in a full-size vehicle carrying around 2 diesel engines and a flywheel and providing enough traction for 0-60 in 4 seconds is not only very expensive to build but physically impossible. In a perfect world, 1 liter of diesel converts to less than 10kWh. The full-size verhicle would have to move in a near vacuum.
    I still agree that many things can be done but I see a lot more potential in large scale installations being influenced by equally large scale political decision (like switching from coal to nuclear) rather than hoping for the average chinese to be able to afford (and want) a fancy green car.

  7. 407
    pete best says:

    Re #399, Don’t have 5 kids then maybe.

  8. 408
    Chris O\'Neill says:

    mugwump:

    But let’s be realistic. China and India are looking at catapulting their children from abject poverty to middle-class in a single generation. It’s very unlikely they’d be willing to jeopardize that for even a 4.5C rise, since the benefit to them far outweighs the cost.

    Burn away folks. It’s only being realistic.

  9. 409
    Anne van der Bom says:

    mugwump:

    I have followed your postings and (as a layman) I find them interesting, although I can only partially follow the science in them. But still, I would like to comment on them and hope you have time to respond.

    #335:

    We’re probably fine if it is 2

    Is this based on something? It seems you are trusting your ‘gut feeling’, but shouldn’t you distrust that? Isn’t that what science is all about? After all, the theory of relativity goes completely against any common-sense-every-day-logic, and so my gut feeling says it’s a load of bollocks.

    GCM’s are made exactly to determine climate sensitivity without ‘gut feeling’. Yet you distrust the scientists that build them, saying they somehow tweak the parameters to get the desired results. In other words: you think the emotions of the climate scientists influence their results. But here you are completely basing your conviction on some feeling of ‘we are probably alright if climate sensitivity is below 2′. This baffles me, especially from someone who (I’ll have to take your word for it) is a scientist himself.

    Your quest for the GCM-less determination of climate sensitivity looks to me like the FDA declaring clinical trials unreliable and demanding a farmaceutical company for mathematical proof of the harmlessness of a new drug.

    The climate is influenced by so many factors, if you start to include them all in your ‘simple’ calculation, what you end up with is something that you would call a ‘model’. Actually, this is what has happened in the climate science community over the past 150 years or so. It started with a simple calculation, to which more and more factors were added until this day in which we have a few dozen GCM’s.

  10. 410
    dhogaza says:

    Not a particularly important point, but the “programming” involved is in regard to the mileage *test* used, not the car itself. Different countries test different driving profiles, and the profiles used to determine official mileage in Japan is more hybrid-friendly than the current test used here (which is less hybrid-friendly than our own test used a few years ago).

  11. 411
    Mick says:

    Jess, there is Uranium on every terrestial body in the solar system and its scattered throughout the universe. There is plenty of energy to go around on current technology.

    Also, if we get fusion we can work with the substantial portion of the entire #$%#$%$ universe that is hydrogen.

    The only energy crises is artificial, caused by creepy environmentalists who are so afraid to die alone they want to create a mass death scenario where everyone has the comfort of a communal end.

  12. 412
    Mark says:

    Mick, there’s thousands (millions?) of tons of gold in the ocean.

    Go help yourself to a few kilos.

  13. 413
    John Mashey says:

    1) For some reason, this thread is now being taken over fantasies about energy & growth.

    2) For a good discussion of climate & energy by someone who actually has a grip on reality, I suggest(Nobel physicist) Burton Richter’s Gambling with the Future. He comments on fusion for example…

    3) As for indefinite growth at our current rates, fueled by ever-better technology, that’s often assumemed by people who’ve had little to do with creating advanced technology, for whom such is indistinguishable from magic.

    More likely, the following biophysical economists have a much better handle on the impact of energy on economics, not just technology:

    Charles Hall, EROI at TheOilDrum. There isn’t any EROI=100 oil left… Study the balloon graph and think about it.

    Charles Hall, home page, read talks, worry whethere neoclassical econ is right or not

    Robert Ayres, Economic Growth (and Cheap Oil). and look for book “The Economic Growth Engine”, by Ayres & Benjamin Warr, ~Feb 2009.

    They claim a substantial part of economic growth comes from energy, or more precisely work = energy*efficiency. For a century, we’ve had more energy, but world oil production looks to be on the bumpy plateau of it’s Peak already, and it’s a few decades until natural gas does it. On Hall’s graph, we need to replace the oil+gas, and cut down the coal way down. That’s ~75-80% of our current energy supply. Good luck to descendants…

    4) All this *can* be dealt with, but it needs some political will to enter the 22nd Century with a 22nd Century economy&energy infrastructure, rather than a badly-broken 20th Century economy littered with stranded assets that don’t work any more. It would have helped had we started a few decades ago.

  14. 414
    J.S. McIntyre says:

    Speaking of “new” technologies…

    12-year-old Revolutionizes the Solar Cell

    “William Yuan, a seventh-grader from Portland, OR, developed a three-dimensional solar cell that absorbs UV as well as visible light. The combination of the two might greatly improve cell efficiency. William’s project earned him a $25,000 scholarship and a trip to the Library of Congress to accept the award, which is usually given out for research at the graduate level…”

    http://blog.wired.com/geekdad/2008/09/12-year-old-rev.html?npu=1&mbid=yhp

    IMHO, arguments surrounding putting off addressing GHGs and their effect upon climate based on vague arguments surrounding the need to “develop” new technologies is something of a non-sequitur. Historically, most technologies tend to be developed in response to perceived need. It follows then that if we begin to address a need, said technologies will invariably be forthcoming, as young Mr. Yuan has demonstrated.

  15. 415
    Diversity says:

    This is one in a series of superb posts, but I learned fron engineers to simplicate and add lightness wherever possible.

    SIMPLICATED PRESENTATION.

    For us non-scientists the two damned uncomfortable facts are:

    - We have reliable measurements of the concentration of carbon dioxide in the air and they are creeping upward year by year.
    - For all concentrations worth thinking about, more carbon dioxide in the air means more energy trapped in and near the surface of the earth.

    The surface of the earth is a rotating, rough ball with a coating of air and water. The air and water flow around in very complex patterns driven by the energy retained. We can expect that:

    - More energy retained will mean that the air and water will be warmer, on average.
    - More energy retained will make the air and water flows more variable, more turbulent, and more likely to produce local extreme conditions.

    That is more carbon dioxide in the atmosphere means that we must expect our climate to get warmer, more varible and more extreme.

    That’s it. It is about as sure-fire as the idea that if you press on the accelerator the car you have never driven before, it will go faster.

    OK, you want to know which things are going to get how much warmer when and where. You want to get an idea of where and when the weather may wreck the crops or the storms remove your house. That is what the wonderfully complicated, but still very approximate, climate models are about. For now think of them as more reliable than today’s models of the economy, but no more reliable than the weather forecasts were 50 years ago. Let someone else argue about how to improve the models; but remember that what you want out of them are better and better estimates of the odds on how badly (or well) things may turn out.

    Since you are human, you ask what can we best do about it. The guys are still working on that. Probably what you and I can best do about it is put presure on and money in to come up with good, effective, workable answers.

    Since you are curious, you want to know how that extra carbon dioxide got in the air. The scientific detectives say that most all the evidence points to us and our ancestors having put it there by burning carbon we dug out of the ground. But wherever it came from, the question is: what we do about it now?

    All the rest is interesting, but not essential.

  16. 416
    RichardC says:

    #388 Mugwumps talks of a 5 year old design instead of the new one, but I’ll go for it. With 10,000 miles a year, savings for increasing mileage from 23 to 46mpg at $4 a gallon is $870 a year. Say you own the car for 3 years. That’s $2600 savings. A 2005 Prius in good condition is $22000 VS a new 2008 price of $22,220. A 2005 Camry in good condition is $13,430 VS a new price of $20,340. Add up the numbers, and the consumer saves $9290 over three years by buying a Prius. Subtract about $290 for interest and $2k for whatever, and it nets out at a $7,000 savings, not including the savings of time by filling up less frequently. (Cost numbers from Kelly Blue Book) Mugwumps, how is a $7000 savings over 3 years unwise economically? Did you forget resale value and that gas prices aren’t $1 a gallon anymore? My condolences on your blunder with the SUV. The market forces which keep a used Prius at new-car value also destroy large SUV resale value. The 2005 H2 lost 53% of its value. A 2008 monster SUV should lose 80% or so in 3 years. Tis scrap metal you’ll own, once Prius-style monster SUVs hit the market.

    Besides, you ignored the increase in oil prices caused specifically by the choice of three corporations to build crap cars, ignored the military cost to “secure” Mideast oil for the crap cars, ignored the absolute tanking of value in Detroit stock (rolling and capital) and evaded the question entirely. Obviously it’s not a free country when it comes to vehicles. People are screaming for efficient cars, and Detroit ignores them. Lynn, a woman without mechanical experience is considering trying to build her own car!

    Quit evading and answer the direct question. How does tripling the efficiency of the nation’s fleet harm the economy? Include all effects such as the obvious halving of gasoline prices and the elimination of the military cost of oil. Your Marie Antoinette style response doesn’t cut the cake. That larger cars are needed by some isn’t relevant. The larger the car, the bigger the effect is, so quadrupling a large SUV’s efficiency is what’s on the table.

    #396 Steve, it depends on how the question is phrased. I can’t fathom any economist saying that tripling efficiency at negligible capital cost would harm the economy. My guess is that the folks you are [not] quoting are pundits, not economists. We’re talking specific actions with specific results. Hybrid and tribrid technology for vehicles, and nuclear pre-heaters for fossil fuel plants. Both save tons of money and reduce emissions by 60% or more as compared to the current machines. Please ask any economist if such paradigm shifts would harm the economy. Be sure to ask if dropping oil prices back to $25 a barrel would harm the economy.

    #398 Mugwumps, you’re right, plastics manufacture does not require fossil fuel. It can be made quite easily from non-fossil hydrocarbons. I also agree with you on tech trajectory. Nano and bio will result in huge paradigm shifts. However, your economic analysis fails because it excludes externalities, including the inherent insurance cost of taking a path. If CO2 emissions have a 10% chance of costing x, then x/10 must be charged by society to compensate. The numbers are so huge that x/10 is the largest component of the price. By excluding the largest component, capitalistic forces can’t function properly. Besides, why not save gobs of money by dropping CO2 emissions by 3/4ths? There is only one answer: vested interests in obsolete systems would lose profit. Profit is NOT the goal of capitalism; reduced end-user cost is. Since individuals can’t build or influence the building of complex modern systems like cars, the whole economic theory shreds, and we end up with push-sold vehicles that are only desired because of TV ads, discounts, and fear. Since there are Hummers out there, folks feel they need equivalent weapons to survive. You’re stuck one equation behind.

    And you’re right, we don’t know whether the results of our little CO2 experiment will be merely very bad, or fully cataclysmic. It’s stupid to continue down a path that is guaranteed to a 95% confidence level to do very bad things simply because we don’t know how horrid it will be. This year’s Arctic ice data is conclusive. All forcings are negative. Solar output is at dead minimum. Zero sunspots, with an average near zero for two years now. Weather conditions optimal for ice buildup, yet the ice volume probably still declined past 2007′s level. Once the sun comes back online and the weather shifts, the Arctic will melt away. Once that happens, Greenland will work on sea level, and Siberia will get busy with CH4 production. Since we’ll save gobs of money by beginning to get off the carbon habit (supply and demand all by itself dictates that), I can’t fathom your position.

  17. 417
    mugwump says:

    RE #407:

    Re #399, Don’t have 5 kids then maybe.

    Too late pete. Which ones would you like me to sacrifice?

    RE #409:

    My gut feeling about 2C sensitivity being ok derives from the fact that we’ve already seen about a 1C rise over the past century or so and the sky has not fallen in. Also, in terms of humanity’s global impact, a 2C increase in temperature from GHGs is the least of our sins.

    RE #413:

    As for indefinite growth at our current rates, fueled by ever-better technology, that’s often assumemed by people who’ve had little to do with creating advanced technology

    Let me guess John, you once had something to do with creating advanced technology? Some of us on the other side do too. I suspect whether one thinks technology can drive growth indefinitely has a lot more to do with one’s political outlook than anything else (rightward leaning optimists versus leftward leaning pessimists).

    I doubt people are claiming indefinite growth at current rates (I certainly am not). When 3/5 of the world is making the transition from 3rd world to 1st world, global growth rates are obviously huge (there’s nowhere to go but up). Once we’re all first world, we’ll likely witness long periods of “punctuated equilibria” where the punctures are caused by significant technological breakthroughs.

    4) All this *can* be dealt with, but it needs some political will to enter the 22nd Century with a 22nd Century economy&energy infrastructure, rather than a badly-broken 20th Century economy littered with stranded assets that don’t work any more.

    The economy is doing fine as far as I can tell. Living standards are rising rapidly across the globe. The main places where things are still relatively moribund are those states afflicted with central planners who think they know what is best for the rest of us…

    It would have helped had we started a few decades ago.

    Thank goodness we didn’t.

  18. 418
    Jeffrey Davis says:

    It follows then that if we begin to address a need, said technologies will invariably be forthcoming, as young Mr. Yuan has demonstrated.

    The magical pixie dust of “need”.

    “Invariably” is overly optimistic and doesn’t match your own “most” and “tend”. And a single invention doesn’t “demonstrate” any kind of invariability. Advance tends to beget advance, but remember that the blight of the Middle Ages followed hundreds of years of Roman know-how. Things do go backward from time to time.

  19. 419

    If we suppose the point of getting gold is to have gold, as bankers’ habit of reburying much of what is dug up would suggest, then seawater is not an economic gold ore: one would have to sell more gold than would be acquired. If element-92 acquisition were similarly pursued for its own sake, acquiring it from seawater would, again, require selling more terrestrially mined element-92 than the seawater extraction would give. However, if the purpose of the marine extraction, as recently demonstrated, had been to get energy, then it would probably have paid off. Those hydrocarbon ropes net many times their own energy of combustion with each soaking, and if their submergence is deep, so that sunlight doesn’t degrade them, they can fetch many loads.

    Seawater [Au] is 1/300 of seawater [element-92].

  20. 420
    Walt Bennett says:

    OT: Looking for community response to Douglass, D.H., and J.R. Christy, 2008: Limits on CO2 Climate Forcing from Recent Temperature Data of Earth.

    http://arxiv.org/ftp/arxiv/papers/0809/0809.0581.pdf

    [Response: We should have a competition for the largest number of hidden (and invalid) assumptions that can be found in ten minutes browsing. Another embarrassing own goal. - gavin]

  21. 421
    Steve Reynolds says:

    Mark: “The Stern report shows differently.”

    The Stern report was not peer reviewed.

    Mark: “And in case you decide that report is partisan, there have been no economists taking up where it gets it wrong.”

    I suggest you look into that. A starting point:

    http://nordhaus.econ.yale.edu/stern_050307.pdf

    Wikipedia has plenty more similar references.

  22. 422
    David B. Benson says:

    Barton Paul Levenson (405) — Nor do the

    Bolivians and Perueans;
    Anadaman Islandsers and Bangladeshi;
    various and assorted Pacific Islanders.

    Nor should those living around the Mediterrean and Black Seas.

  23. 423
    Steve Reynolds says:

    John Mashey: “All this *can* be dealt with, but it needs some political will to enter the 22nd Century with a 22nd Century economy&energy infrastructure…”

    I will agree that far, but the political will needs to be to stop making political decisions about winning and losing technology (despite how attractive and lucrative having that power is to politicians).

    I looked at your reference to Charles Hall. I got to the end of the long PowerPoint presentation; I’ll agree that recycling paper is bad.

  24. 424
    mugwump says:

    RE #420: My first reaction is they seem to have radically underestimated the uncertainty in the trend.

  25. 425
    David B. Benson says:

    Even If Greenhouse Gas Emissions Hold Steady, Warmer World Faces Loss Of Biodiversity, Glaciers:

    http://www.sciencedaily.com/releases/2008/09/080917145509.htm

    ————-
    Steve Reynolds (423) — Recycling paper is bad?

  26. 426
    Rod B says:

    Martin (389), true (the safety margin thing) but don’t forget the major physical validation that goes on with aerodynamic models, which can’t be done with GCMs (and others, stellar and cosmology, e.g.). Also, some truth in the validation of circulation models; but that ignores the great lengths that climatologists go to disconnect weather from climate models; actually not great lengths per se but the reasons for the great lengths — simply that they are different.

  27. 427
    David B. Benson says:

    No plant CO2 relief in warm world:

    http://news.bbc.co.uk/2/hi/science/nature/7620921.stm

    so the future climate sensitivity may be higher than anticipated.

  28. 428
    CL says:

    mugwump, 417

    “The economy is doing fine as far as I can tell.”

    Erm, I thought we are in an unprecedented economic crisis.

    Or is it that I am just poorly informed and out of touch ?

    http://organizationsandmarkets.com/2008/09/17/the-financial-crisis/

    http://www.leap2020.eu/GEAB-N-22-is-available!-Global-systemic-crisis-September-2008-Phase-of-collapse-of-US-real-economy_a1298.html

    http://www.countercurrents.org/grey180908.htm

    http://www.countercurrents.org/lendman180908.htm

    ‘shortstop stableboy’. Sounds like a horse raceing tip

  29. 429
    Ray Ladbury says:

    Mugwump–re 413: Google John Mashey.

    Technology on demand has not been my experience in life. Simply assuming it will be there when we need it sounds a wee bit too much like the “success driven schedules” proposed by some project managers I’ve known. I agree that increases in technology represent the only real (read “nonextractive”) growth. I agree that technology is the only way we will get out of the mess. I am simply not so sanguine that the technology will come along quickly. It will take a massive development effort.

    And while you may think we’re fine with only 2 degrees per doubling, I would suggest you consider what happens when the permafrost melts and belches out a bunch of CH4 or when the clathrates start to thaw or when the North pole is actually ice free. There are lots of uncertainties. They do not favor complacency.

  30. 430
    Jim Eager says:

    Re mugwump @417: “The economy is doing fine as far as I can tell.’

    Don’t listen to the news much, eh?

    OK, I’ve read enough of what you have to say. It’s now quite clear that as with almost all delayers/deniers/skeptics/contrarians (pick your own label) it’s not really about the science at all for you. What it’s really about is how the notion of taking action to deal with anthropogenic climate change is at odds with your own political ideology. Which means you really have nothing more to contribute to the discussion but more political rhetoric, and I can get plenty of that elsewhere, if I were at all interested. I’m not.

  31. 431
    J.S. McIntyre says:

    re 418. Jeffery, thank you for your comments.

    An apology. Not to quibble, but it appears you are missing the point. Mr. Yuan’s achievement is illustrative of what happens when people apply themselves to a problem (re a “need”). While you could argue that his solar cell is more an example of innovation as opposed to original invention, this does nothing to change the real point that he was responding to a perceived problem and providing a solution. In short, I was holding him up as an example of what we’re beginning to see in terms of responses to the problem. (And what he has done is not insignificant, else one has to wonder why a seventh grader would receive this award in recognition of what he is done, an award normally handed for research at a graduate level.)

    You write: ““Invariably” is overly optimistic and doesn’t match your own “most” and “tend”.”

    I will repeat – we invariably tend to address needs, whether on a personal, individual level, or on a societal level. There is nothing Pollyannish about this observation; I certainly am not making the specious argument often heard from the anti-AGW community of skeptics that we will “innovate” our way out of this problem. Nor am I suggesting the innovations/inventions/solutions will come in the nick of time, an argument against which seems to underscore the tone of your response to my comments.

    Quite to the contrary: from where I sit, we may have run out of time to formulate a response that will “solve” the problem. Or, considering the foot-dragging that AGW skepticism helps to facilitate, and given the prevalent lack of urgency that characterizes the response to AGW in many quarters, by the time we come to our senses, these “responses” will be too late, because the will and desire to implement them was lacking when they could have made a difference. Instead, more and more it seems, at least from my perspective, the conversation these days is morphing from ”this is how we can “stop” or “reverse” AGW”, and becoming, instead, a conversation focused on how well we’re going to be able to adapt to a changing environment.

    In summation, you are right; solutions may come too late. But that was not my point; and goes off-track from the real focus of my posting, which was to suggest the argument that we should wait for technological innovation before we do anything is contrary to what we see as a something of a norm in human history. I certainly wasn’t discussing absolutes as you seem to infer; I thought that rather clear..

  32. 432
    Anne van der Bom says:

    mugwump

    My gut feeling about 2C sensitivity being ok derives from the fact that we’ve already seen about a 1C rise over the past century or so and the sky has not fallen in.

    The fact that the first 1ºC did not make the sky fall in doesn’t prove that the second 1ºC will be equally mild on us, and the third, fourth, etc.

    You confirm that on this scientific matter your opinion is based on your gut feeling. How much of a scientist are you?

  33. 433

    Mick posts:

    The only energy crises is artificial, caused by creepy environmentalists who are so afraid to die alone they want to create a mass death scenario where everyone has the comfort of a communal end.

    You forgot to mention the UN black helicopters.

  34. 434
    mugwump says:

    RE #432:

    The fact that the first 1ºC did not make the sky fall in doesn’t prove that the second 1ºC will be equally mild on us, and the third, fourth, etc.

    Right, the second 1ºC almost certainly won’t be equally mild. But it probably won’t be a big deal either. As for the third – that’s in the grey area. The fourth? I already said I believed 4 degrees quickly would likely require a lot more action than at present, in which case we had better get China and India on board which I doubt we can do.

    You confirm that on this scientific matter your opinion is based on your gut feeling. How much of a scientist are you?

    One of the best, thankyou for asking. There are few reports out there that another 1ºC of warming will be a disaster.

  35. 435
    mugwump says:

    RE #430 Jim Eager:

    It’s now quite clear that as with almost all delayers/deniers/skeptics/contrarians (pick your own label) it’s not really about the science at all for you. What it’s really about is how the notion of taking action to deal with anthropogenic climate change is at odds with your own political ideology.

    Rubbish. Tackling AGW on the basis of wildly uncertain information is at odds with common sense.

    [Response: So tackling economic crises on the basis of wildly uncertain information is at odds with common sense too? You have it completely wrong. Decisions are almost always made with uncertain information (we could dispute the 'wildly'). - gavin]

  36. 436
    mugwump says:

    RE #429 Ray:

    Technology on demand has not been my experience in life.

    I am not arguing for “technology on demand” as such. I am arguing that the technological progress of the last 150 years teaches us that technology of 150 or 200 years hence will be so vastly superior to today’s that it is crazy not to take that into account.

    In particular, we are on the cusp of a genetic engineering revolution that will rival the computer revolution in it’s breadth and growth rate. We’re barely at the vacuum-tube stage today.

  37. 437
    Walt Bennett says:

    ReL #420

    Gavin,

    Thanks for the response. Of course, being a layman, I have no way of knowing which invalid assumptions you refer to. I rely on experts to critique other experts in language which is accessible to me.

    I have little doubt that the Christy paper has flaws; else, why go to E&E with it, a la Beck? I was highly informed by critical response to that paper, in this very space as well as elsewhere.

    Since at least Lindzen also downplays the forcing of increased CO2, I would say that there is some weight to the theory. It may, in light of day, have no merit. In that case, shine the light.

  38. 438
    Barelysane says:

    David B. Benson, 427

    That study was total dross. One species, change one factor in an already harsh environment. The only
    thing you can learn from that is to ignore all BBC reporting. Completely failed to mention what might happen where water isn’t in short supply.

    Jim Eager, 430
    “It’s now quite clear that as with almost all delayers/deniers/skeptics/contrarians (pick your own label) it’s not really about the science at all for you”.
    As someone who would fall into your rather narrow caategorisation, i’d like to say it is most definately about the science. Having spent the last year or so trawling through the internet looking at various
    research and summaries to try to get a handle on the current state of knowledge. I’ve concluded that a) we don’t know a great deal about the climate yet, and b) CO2 is almost certainly not the primary driver of climate change.

    I never generally come on sites like this as i dislike getting covered in mud, but i’m having a slow day and some of what i read here is breathtakingly either poorly informed or very selectively informed. Congratulations to mugwump for sticking it out so long.

  39. 439
    Nick Gotts says:

    “In particular, we are on the cusp of a genetic engineering revolution that will rival the computer revolution in it’s breadth and growth rate.” – mugwump@435

    Right. And fifty years ago, we were going to have abundant fusion power, bases on the moon and Mars, superhuman artificial intelligences, household robots and personal helicars by now. Even your own example, the “genetic engineering revolution”, fails to make your point. Where are the radical advances in medicine that “gene therapy” was going to deliver?

  40. 440
    Jim Eager says:

    Re Barelysane @438: “I’ve concluded that a) we don’t know a great deal about the climate yet, and b) CO2 is almost certainly not the primary driver of climate change.”

    I’d say the name you choose to post under is inaccurate.

  41. 441
    mugwump says:

    RE #435:

    Response: So tackling economic crises on the basis of wildly uncertain information is at odds with common sense too?

    I really don’t think you want to go there gavin.
    Or if you do, fine by me.

    When climate sensitivity and its consequences, and the consequences of acting to drastically cut CO2 emissions, are as well understood as the current economic crisis and its consequences, then I will agree to act.

    [Response: Glad to hear that. Perhaps you'd like to point me to the economists' consensus reports over the last 15 years that predicted the sub-prime mortgage debacle and provided projections of what would happen under 'business-as-usual'? Or a paper from 1988 predicting current economic trends to within 10%? I find it amazing that you think we have a predictive capability in economics that is in any way comparable to that of climate physics on any time scale. Asian financial crisis? S&L debacle? Even China's spectacular growth? How far ahead were any of those things predicted? Compare to the 1992 paper predicting the impact of Pinatubo.... - gavin]

  42. 442
    Nick Gotts says:

    Barelysane@ 438: “Having spent the last year or so trawling through the internet looking at various research and summaries to try to get a handle on the current state of knowledge. I’ve concluded that a) we don’t know a great deal about the climate yet, and b) CO2 is almost certainly not the primary driver of climate change.”

    Care to share your reasons for dismissing the scientific consensus that CO2 is the primary driver of (current) climate change? If not, why should anyone believe you when you assert that it’s “about the science” for you? I, for one, don’t.

  43. 443
    Steve Reynolds says:

    David B. Benson: “Recycling paper is bad?”

    I’m not sure why Charles Hall thinks so, since I did not see it explained in his presentation, but I think production of the energy required to recycle (including transportation and process) generally releases a lot of CO2. Putting used paper in a landfill sequesters the carbon.

  44. 444
    Marcus says:

    RE: #420: Where to start?

    First: they ignore the effect of the oceans and heat uptake. Globally, the effect of oceans is to add a delay to temperature response to forcing. Regionally, where there is more landcover you expect a higher temperature response, and where there is less landcover (for example, the tropics) you expect a smaller temperature response.

    Second: High latitude response: I find it stunning that Christy doesn’t even acknowledge the well known (and predicted) property of the climate system that includes greater relative warming at high latitudes due to snow + ice albedo feedback as well as higher relative land surface area. It is surprising that no reviewers objected to this, either.

    Third: It is well known that tropical satellite data has the largest uncertainty, and yet this is what Christy et al. concentrate on?

    Fourth: “However, recent studies suggest that the value of g is much smaller”: then they pick out 4 citations, compared to about 10000 that suggest that in fact the value of g is not much smaller. And of those 4 citations, I saw Schwartz’ talk at AGU last year, and it was pretty much junk (see realclimate discussion on how his method of determining sensitivity can’t even get model sensitivity right, so how can it get real world sensitivity right?)

    I’m sure there are more, but that’s what I pick up in a quick read.

  45. 445
    Mark says:

    Barelysane, #438.

    Why is it when it’s complicated, you deny it because it’s “too complex, you must be making some of that up” and when it’s simplified, it’s “the only thing you can learn is to ignore all BBC reporting”?

    How about you *don’t* come on these sites? You’ve nothing to add but noise.

  46. 446
    SecularAnimist says:

    Barelysane wrote: “I’ve concluded that a) we don’t know a great deal about the climate yet …”

    You are wrong.

    Barelysane wrote: “… and b) CO2 is almost certainly not the primary driver of climate change.”

    Wrongo again.

    Barelysane wrote: “some of what i read here is breathtakingly either poorly informed”

    Your own “conclusions” are breathtakingly wrong, indicating that you are a poor judge of whether others are “poorly informed” or not.

  47. 447
    CobblyWorlds says:

    “a)

    we don’t know a great deal about the climate yet,”

    Radiative processes (incoming short wave / outgoing longwave), latent and sensible heat, Clausius Clapeyron, aerosol dimming, Hadley Cell Expansion, Pinatubo/Krakatoa/Tambora, greater northern hemisphere warming/meso & stratospheric cooling/increasing diurnal range – as predicted by theory. Passive Microwave temperature determination, CERES, MODIS, Royer Compilation, Climap, Julian Madden Oscillation, Hadley Cells, Ferrel Cells, Brewer Dobson Circulation, ENSO/QBO/NAO-AO, Polar Vortices, Antarctic Circumpolar current, Beaufort Gyre/Transpolar Drift, Pinatubo, Mars vs Venus vs The Earth, CFC-Ozone link…. That’s just off the top of my head. Oh yeah – Hansen 1988.

    We don’t know everything, but we know enough to know what we’re doing to the Earth is likely to be a problem.

    “b)

    CO2 is almost certainly not the primary driver of climate change.”

    Depends when you mean e.g.
    In the glacials: No, it was an amplifier.
    Now: Yes, it’s the primary driver of warming.*

    *Given the weight of evidence on this point I consider any probabilistic qualification to be superfluous.

  48. 448
    Figen Mekik says:

    Barelysane,
    If you are so sure everyone is wrong and poorly informed on this site, why not use your real name? It doesn’t take a lot to argue against everything using no science and an alias. Most people who really understand and contribute to the science on this site have no trouble using their real names and credentials. They are willing to put who and what they are on the line to be ridiculed because they understand the science and believe their opinions have merit.
    You say “Having spent the last year or so trawling through the internet looking at various research and summaries to try to get a handle on the current state of knowledge.” Instead of trawling the internet, how about rreading some peer reviewed scientific literature and coming back with an informed opinion? Then you can have the courage to use your real name and enter into a meaningful and productive discussion about the science.

  49. 449

    mugwump writes:

    There are few reports out there that another 1ºC of warming will be a disaster.

    I take it you don’t live in Australia.

    Global warming is already a disaster. And it’s going to get worse.

  50. 450

    Barelysane writes:

    CO2 is almost certainly not the primary driver of climate change.

    It is almost certainly the primary driver for the present global warming, however.


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