ecoli Posted March 10, 2008 Posted March 10, 2008 http://www.dailytech.com/Researcher+Basic+Greenhouse+Equations+Totally+Wrong/article10973.htm According to one physicist/ climate modeler, there was a grievous error made some time back that propagated throughout modern global warming models. Is this story accurate? What's the deal? Hopefully some physics people can take a look and explain it to the rest of us.
Mr Skeptic Posted March 10, 2008 Posted March 10, 2008 I think I found the original paper [warning, pdf]. It's in English. I'm no climatologist though.
swansont Posted March 10, 2008 Posted March 10, 2008 I don't think anyone is proposing a runaway greenhouse scenario. I suspect that "infinitely thick" is referring to optical thickness; that would be the limit where the atmosphere becomes opaque. I'm not a climatologist, but I can't see offhand why that's an unreasonable limit. From http://climatescienceskeptic.blogspot.com/2008/03/beginning-of-end.html An interesting theory was proposed by Dr. Ferenc Miskolczi, a relatively unknown European scientist. His theory, through the combination of various atmospheric mathematical laws, essentially states that the optical depth of the greenhouse gases in the atmosphere must remain constant. If you assume constant optical depth, I don't have a hard time believing that you'd come to a very different conclusion about global warming. But in response, I say, "Venus"
ecoli Posted March 11, 2008 Author Posted March 11, 2008 well, allegedly, he's predicted Mars's warming accurately. Or defined it's past warming, rather.
bascule Posted March 11, 2008 Posted March 11, 2008 As an outside observer to the process of atmospheric research, I can certainly assure you that "boundary conditions" of all types were heavily considered in the models I was working with, insomuch as a lowly system administrator heard the word on a day-to-day basis. Present knowledge of climate change isn't derived from just a "set of differential equations." Those equations are among innumerable ones fitting a variety of different physical systems which figure into a general circulation model. The cumulative model is composed of a set of mini-models, all of which work in conjunction and feed data back and forth between each other, and in conjunction produce a realistic reconstruction of the historical record. An error in any part of the system would have to be compensated for by errors in other parts of the system which are able to balance out and produce something which appears historically accurate. Unless climate scientists have chanced upon such a configuration, and overlooked gross errors in multiple problem domains, they're onto something. It also helps to explain why current global climate models continually predict more warming than actually measured. No? They've continually underpredicted the actual warming... The equations also answer thorny problems raised by current theory, which doesn't explain why "runaway" greenhouse warming hasn't happened in the Earth's past. Perhaps no species were digging carbon compounds out of the ground and burning them... The new theory predicts that greenhouse gas increases should result in small, but very rapid temperature spikes, followed by much longer, slower periods of cooling -- exactly what the paleoclimatic record demonstrates. At what other time in history were carbon sinks being actively emptied into the atmosphere by physical processes at the rate they are presently? Bottom line: I think this article sucks. WTF?
swansont Posted March 11, 2008 Posted March 11, 2008 well, allegedly, he's predicted Mars's warming accurately. Or defined it's past warming, rather. I can see that the atmosphere of Mars fits the "semi-transparent" boundary conditions more readily than earth's atmosphere does.
ecoli Posted March 12, 2008 Author Posted March 12, 2008 Aren't there like 19 major scientific organisations studying and verifying global warming independently of each other anyway? I find it hard to believe that one error could jump through the whole system and affect the whole theory when so many different independent groups are looking at it. Not only are scientists skeptical people, aren't they also just a teeny weeny bit competitive? Wouldn't many young scientists want to prove what "hot stuff" they are by disproving some theory or other? It just seems to me that too many scientists been studying this for too long to suddenly go "Wooops, forgot to carry the 1" or whatever. Sure, but part of science isn't rejecting ideas simply because they would inconveniently disprove a previous body of work. If that was the case, science would be nowhere today. I think this work should be taken seriously, but if shown to be incorrect, by peer review, quietly shown the door. From the article, it didn't sound like this scientist was some crackpot troother theorist . Probably just some climatologist who fiddled with the numbers and found something different. You can almost be sure that the mass media is exaggerating the significance of the report, even from the scientist's perspective. I don't really understand the math from the original paper, but I would urge everyone to base their arguments for or against off of that, rather than the popular press article.
iNow Posted March 12, 2008 Posted March 12, 2008 Look at its sources: prisonplanet.com, infowars.com and related websites. He's completely disingenuous, and engages in repeated logical fallacies ta boot. They're emphasizing some appeal to conspiracy, strawmanning the actual work being done by climatologists (who actually calls it a "runaway greenhouse effect" anyway), and just engaging in denialist tactics to sow the seeds of doubt. It's complete and utter rubbish, and if it wasn't, then it shouldn't be too hard to prove me wrong. So, go ahead, I dare ye. The math from the original paper is all well and good, but it is not representative of reality and completely distorts our actual understandings for... seemingly... the sheer purpose of fostering additional doubt.
ecoli Posted March 12, 2008 Author Posted March 12, 2008 Look at its sources: prisonplanet.com, infowars.com and related websites. Where does it source those? The math from the original paper is all well and good, but it is not representative of reality and completely distorts our actual understandings for... seemingly... the sheer purpose of fostering additional doubt. fostering doubt or debate? and how is it not representative of reality? (for someone who doesn't understand the maths)
iNow Posted March 12, 2008 Posted March 12, 2008 Where does it source those? It's a blog, so my comment was specific to the author. Michael Asher, Alex Jones... Look at his other article there where he engages in the same disingenuous nonsense (he is literally making sh1t up): http://www.dailytech.com/Survey+Less+Than+Half+of+all+Published+Scientists+Endorse+Global+Warming+Theory/article8641.htm fostering doubt or debate? IMO, doubt, and nothing more. and how is it not representative of reality? (for someone who doesn't understand the maths) As swansont already pointed out, he assumes constant optical depth. As bascule already pointed out, he misrepresents context. As peakoilman already pointed out, he pretends that all of climate science is contingent on this one equation and that all people researching it independently have made the same fault. Multiple statements within the article are false, and the logical fallacies are rampant... strawmen, appeals to authority, appeals to conspiracy, and a bunch of hand waving. Suggesting that all of climate science is pivoted on the "runaway greenhouse model" is nonsense. AFAIK, the runaway greenhouse effect idea has never been seen outside of speculative and non-scientific writings which were themselves done in the 70s. He suggests that climate science is based entirely on “equations derived over 80 years ago, equations which left off one term from the final solution” describing radiative equilibrium... and current computer models don't even use these (not as their only component, anyway). Again, it is nothing more than an unrepresentative denialist strategy and an insulting waste of time. Just do a search on Michael Asher's name... It's not hard to get some context around his background and to find where he's been repeatedly debunked and proven intellectually dishonest.
Chris C Posted March 12, 2008 Posted March 12, 2008 Dailytech nonsense aside, I have not looked into Miskolczi but I see no evidence (yet) to call him a wingnut or liar or what have you, though I can say this paper will not go very far (that is, revolutionize our textbooks, flip science upside down, win a nobel, etc). At best, a known journal would have been nice. I have read roughly the first 25 pages of the original document in detail. Most of the mathematics is rather standard textbook material, and although it looks fancy it amounts to simple energy balance equations which translate to the fact that the net solar radiation at the top of the atmosphere (TOA) must equate to the outgoing longwave radiation at the TOA. In addition, the surface energy budget must close to zero after accounting for all the surface terms (i.e., convection, conduction, upwelling heat from the mantle, downward solar, downward IR, upward IR, etc, etc). This paper also does not assume constant optical depth as iNOW puts it (see first full paragraph on pg. 22). However, I do not think this paper gives full justice to the TOA energy balance, and over emhasizes what happens at the surface. The planet does not necessarily warm on the simple basis that more longwave radiation is absorbed and emitted downward, but because the net radiation downward is greater than zero until the planet can come back to equilibrium. That is simply due to the fact that when you add CO2, the same amount of solar radiation is being absorbed, but the planet is emitting less. I tried to explain this in very much detail, but with laymen terminology in these two posts http://chriscolose.wordpress.com/2008/03/09/physics-of-the-greenhouse-effect-pt-1/ http://chriscolose.wordpress.com/2008/03/10/physics-of-the-greenhouse-effect-pt-2/ There are several fatal assumptions in this paper, such as the idea that water vapor should decrease when you add CO2 (middle to end of page 23). They gave a quick paragraph on this, without any mention of the mainstream views on this subject. Venus is an example of immediate falsification by example, which clearly had a runaway greenhouse effect. The paper says that the OLR must increase for the planet to come back to balance, but in the runaway case this happens only after the Kombayashi-Ingersoll limit (see my pt. 2) is exceeded and the oceans have evaporated. The original paper has only to say this: "At this time the Venusian atmosphere is not included in our study. The major problem with the Venusian atmosphere is the complete cloud cover and the lack of knowledge of the accurate surface SW and LW fluxes." This is pure dismissal. The Venus surface receives considerably less sunlight than Earth, and is yet much, much hotter. Not saying we know every detail about Venusian clouds, but the fact a runaway occurred on the well-known basis of CO2 does not give this paper a good start. So far, the only way to argue for the low climate sensitivity in the paper is to introduce substantial negative feedback. This paper has not done this in any justifiable sense, and has given a sensitivity far lower than the Planck response. There is a lot more explaining to do: Cretaceous hothouse? Faint Young sun in the archaean times? Ice Ages? PETM? 2
ecoli Posted March 12, 2008 Author Posted March 12, 2008 It's a blog, so my comment was specific to the author. Michael Asher, Alex Jones... Look at his other article there where he engages in the same disingenuous nonsense (he is literally making sh1t up): http://www.dailytech.com/Survey+Less+Than+Half+of+all+Published+Scientists+Endorse+Global+Warming+Theory/article8641.htm oh, well I was only interested in that specific blog, where he only references (what appear to be) reputable sources... Universities and Brookhaven national lab (which you better not diss because I've worked there! Probably in the same building as the scientist he referred to, though my research never really panned out. I'm just not a maths person.) Just do a search on Michael Asher's name... It's not hard to get some context around his background and to find where he's been repeatedly debunked and proven intellectually dishonest. well, like I said, I'm not interested in the blog, but in the research. edit: Thanks for the great post Chris C... you're clearly very knowledgeable on this subject and I most certainly defer to your judgment on the matter. You should start up a SFN blog on the subject, since I see you're already familiar with Wordpress. This site could use more intelligent bloggers. You'd make a good addition.
Cap'n Refsmmat Posted March 12, 2008 Posted March 12, 2008 edit:Thanks for the great post Chris C... you're clearly very knowledgeable on this subject and I most certainly defer to your judgment on the matter. You should start up a SFN blog on the subject, since I see you're already familiar with Wordpress. This site could use more intelligent bloggers. You'd make a good addition. That is, as soon as I make them work again. Whooops. (If you're having trouble posting on your SFN blog, I'm on it.)
iNow Posted March 12, 2008 Posted March 12, 2008 I second the gratitude to Chris. Thank you for showing me where I erred.
Chris C Posted March 12, 2008 Posted March 12, 2008 By the way, the greenhouse effect in the Martian atmosphere is extremely small because of the very thin atmosphere (roughly 7 millibars compared to Earth's 1000 millibars). I've not looked at the numbers, but even with a full CO2 atmosphere, I'd be surprised if its atmosphere got it even 10 C warmer than in a no atmosphere case. CO2 is also a short lived gas on Mars (unlike Earth) because it gets cold enough there for CO2 to condense. Since the sun was ~25-30% fainter in the early stages of the planet, a much denser atmosphere (and water vapor feedback) would enhance the greenhouse effect substantially on Mars, and that would be the only way to get liquid water on the early martian planet.
ttowntom Posted March 13, 2008 Posted March 13, 2008 No? [Models have] continually underpredicted the actual warming...Stuff and nonsense. IPCC AR3 (2001) gave an ensemble of model predictions, which ranged from 1.5C up to nearly 6.0C in total warming: Yet the observed decadal warming trend now stands at only 0.14C: http://vortex.nsstc.uah.edu/public/msu/t2lt/tltglhmam_5.2 The continual overprediction of warming in fact explains why AR4 downgraded their forecasts for maximum warming substantially.
iNow Posted March 13, 2008 Posted March 13, 2008 Since your graph above is intended to show that the models over predict actual climate, 1) Where are actual observations on this graph, the observed temperature changes? (an overlay would be nice) 2) Your graph is for the century, starting in 2000, but we are only 8 years in, less than 1/10th. Again, how is this relevant to your argument?
ttowntom Posted March 13, 2008 Posted March 13, 2008 There is a lot more explaining to do: Cretaceous hothouse? Faint Young sun in the archaean times? Ice Ages? PETM?The "classic" explanation of the EFS paradox is a hypothesis without observational data to support it, and one that involves two wholly separate processes (the sum warming & greenhouse gases declining) which just happen to coincidentally work in lockstep to keep temperatures relatively even. I think Dr. Shaviv's hypothesis explains this much better -- a young sun rotates much faster, creating a much stronger solar wind. The increased corpuscular radiation compensates for much of the lower irradiance. As for explaining past climatic variations, from the Cryogenian to the Paleocene-Eocene boundary, the standard explanation involves Milankovich-cycle induced triggers, followed by feedback effects, some of which include GHG-based forcings. Nothing in the paper contradicts that. It merely resets the relative balance of the various factors somewhat. If you believe Miskowlczi is discounting the greenhouse effect, you've misread the paper. The maximum bound from CO2-based forcing is likely in the range of 2-3C, a figure which -- again, according to Miskowlczi, agrees extremely well with TIGR data. Venus is an example of immediate falsification by example, which clearly had a runaway greenhouse effect.Venus certainly seems to have a greenhouse effect, but claiming its a proven runaway process is off base. Venus merely demonstrates the upper bound for an atmosphere with 250,000X as much CO2 as essentially zero H2O is much higher-- again, not surprising. The fact remains, that with zero data on surface fluxes, one can't fit *any* model of surface temperatures to Venus. It's all simply supposition, and the author rightly avoids it. And as an aside, I must point out that attributing all the Venusian excess heat on GHGs is no more than supposition itself. The Magellan mission found evidence of extraordinarily high levels of volcanism on Venus, with a surface dominated by lava plains. For all we know, much of that excess heat is due to geologic processes. Look at its sources: prisonplanet.com, infowars.com and related websites.Eh? The only links I see in that article are to a peer-reviewed Hungarian journal, and a peer-reviewed paper from Brookhaven Labs. Other than that, it has a few quotes from the actual scientists involved, and that's it. So where are you getting this "prisonplanet" strawman?
iNow Posted March 13, 2008 Posted March 13, 2008 You should read the entire thread before replying (I know, it's quite difficult being almost a full page already). I've already responded to that.
ttowntom Posted March 13, 2008 Posted March 13, 2008 Your graph is for the century, starting in 2000, but we are only 8 years in, less than 1/10th. Again, how is this relevant to your argument?Err, that's a line graph. It's for the *entire* period from 2000 to 2100. And yes, we're only 8 years in, but you can't compare predictions to a reality which has not yet occurred. Nevertheless, we can compare predicted decadal rises from the 1990s with the true situation 10 years later. And Voila! We see huge discrepancies already. If the models aren't accurate even 10 years in, what does that say about their performance over 100 years? Model predictions have continually overstated temperature increases. The IPCC scaled *back* predictions in the 2007 AR4 report, to bring them better in line with reality.
iNow Posted March 13, 2008 Posted March 13, 2008 It's for the *entire* period from 2000 to 2100. And yes, we're only 8 years in, but you can't compare predictions to a reality which has not yet occurred. That's exactly my point. Your suggestion seems to be that the the models over predict warming, but the observations have not yet occurred. The graph did not support your argument. It's like I said, "farmers are growing fewer oranges than models predicted." You then reply, "no, actually farmers are growing more oranges than models predicted. Here is a projection for orange growing over the next century to prove my point." I reply, "Uhmm... I was talking about actual crop harvest observations, not projections of harvest." You then say, "Errmmm, you can't compare predictions to a reality which has not yet occurred." Do you follow where the communication break down seems to be? If I draw a line near the beach on a wall that has been built in the sand, and I say that "Over the next 4 years, this will be the average height of the waves which strike this wall," you cannot say my prediction is wrong when I'm unable to tell you exactly where the next wave is going to hit, or if the waves have a different average during that week.
ttowntom Posted March 13, 2008 Posted March 13, 2008 That's exactly my point. Your suggestion seems to be that the the models over predict warming, but the observations have not yet occurred. And yet you have no problem claiming those same models "underpredicted" warming? Odd, since you claim to believe it's too early to tell. The fact remains that those observations *have* come to pass. The models predicted a decadal warming trend that ranged from of 0.15C to nearly 0.6C. This is far above what we've actually seen for the past 10 years. The models overpredicted warming, and seriously so.
swansont Posted March 13, 2008 Posted March 13, 2008 And yet you have no problem claiming those same models "underpredicted" warming? Odd, since you claim to believe it's too early to tell. The fact remains that those observations *have* come to pass. The models predicted a decadal warming trend that ranged from of 0.15C to nearly 0.6C. This is far above what we've actually seen for the past 10 years. The models overpredicted warming, and seriously so. You're comparing apples and oranges. Historical predictions were not made with the same models, and 10 years is a relatively short timescale over which to make comparisons. What were the predictions that were made in 1980? 1970? Did they under- or overpredict the warming we've seen in the last 30-40 years?
iNow Posted March 13, 2008 Posted March 13, 2008 And yet you have no problem claiming those same models "underpredicted" warming? Odd, since you claim to believe it's too early to tell. Look back at this thread. I never claimed any such thing. You seem to be misapplying a claim to me, a claim which I never even made. Regardless, that's beside the point which I HAVE been making. Your own point is still in refute.
ttowntom Posted March 14, 2008 Posted March 14, 2008 What were the predictions that were made in 1980? I'm glad you asked! James Hansen's (NASA GISS) predictions from 1987 (published in an 1988 paper) are quite illuminating. They were, in fact, used for the basis of the IPCC's first assessment report, and this paper (along with Hansen's later works are still heavily cited today): He calculated three scenarios. Scenario A assumed continued growth of CO2 emissions at current levels -- this is in fact very close to what has happened in the 21 years since he made those predictions. And what was the calculated temperature rise by 2008? A full 1.0C above the 1951-1980 mean. What did temperatures actually rise? As of last month, they're 0.2C. Warming was overpredicted by 500%. The *coolest* of the 3 was based on the assumptions that the world would stabilize CO2 emissions by the year 2000. Even for that scenario, Hansen predicts a warming of 0.62C by 2008. But -- even though emissions have continued nearly unrestrained, warming has only been a tiny fraction of that. The facts are clear. Models predictions from the 1980s and 1990s were hugely overstated. People who claim the "models predicted less warming than we've seen" are wrong, plain and simple. Source to Hansens's 1988 paper is here: http://pubs.giss.nasa.gov/docs/1988/1988_Hansen_etal.pdf
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