There is a new paper in Science this week on changes to atmospheric visibility. In clear sky conditions (no clouds), this is related mainly to the amount of aerosols (particulate matter) in the air (but is slightly dependent on the amount of water vapour as well, which is corrected for in this study). The authors report that the clear-sky visibility has decreased almost everywhere (particularly in Asia) from 1973 to 2007, with the exception of Europe where visibility has increased (consistent with the ‘brightening trend’ reported recently). Trends in North American stations seem relatively flat.
There is another story that didn’t get as much press when it came out late last year but that is highly relevant to this issue – whether any of the efforts that the Chinese authorities to reduce air pollution ahead of the Olympics last year had any impact. To the extent that they did, they might point the way to reducing aerosols and other pollutants across Asia, but it might also reveal how hard it is to do so.
The press release and abstract for the Science paper link their results to the ‘global dimming’ trends we have reported on in the past, but it’s worth perhaps pointing out that previous studies (and the term ‘global dimming” itself) have referred to all-sky conditions. So that includes changes in clouds – which are obviously a big factor in how much sunlight gets to the surface. Looking at the clear sky conditions (i.e. only when there are no clouds) can help attribute changes to aerosols or atmospheric dynamics say, but since aerosols affect clouds (the ‘indirect effect’) as well as circulation too, it is only a partial estimate of the true impact of aerosols.
But getting back to the Olympics…. Monitoring of pollutants near the surface has improved enormously in recent years with the various satellite instruments now in orbit (MOPITT, GOME, OMI and TES for instance (sounds like a comedy revue team, no?)). These instruments detect specific frequencies where pollutants are known to absorb and so can give a birds eye view of where the pollutants are and how they are changing. Among other things, the satellites can detect ozone, NOx, SO2, the total amount of aerosols and carbon monoxide. Each of these have different atmospheric lifetimes and so can be used either to detect point sources (from pollutants that only last a short time) or long range transports of pollution (from the longer lived pollutants). NO2 (a big component of NOx – which lumps together NO and NO2all of the reactive nitrogen oxides), is very short-lived and so tells you a lot about local sources. Carbon monoxide has a longer lifetime (a couple of months) and so can show the long-range impacts. Many of these pollutants have related industrial sources (car exhausts, coal burning, industrial production etc) and so can be used as proxies for many other pollutants (such as specific aerosols) which can’t (yet) be directly measured.
What do the results show? The team at GSFC have released preliminary images from the NO2 analysis showing the before and during the pollution controls. In both images, Beijing shows up as a huge hotspot of pollution, but relatively, the levels during the Olympics were significantly smaller:
August 2008 levels were therefore about 50% less than a similar period the year before. Meanwhile values at other hotspots in China were steady or got even worse. So there was a significant effect, but the scale of the task was indeed Olympian.
Re #50, Monbiots profile is not that high as to save the Amazon now is it.
Glen, thanks for the lucid discussion on cap-and-trade vs. carbon tax. I was interested to see mention of one of the points that I’ve been wondering about at times: that cap-and-trade should be much better suited to international implementation than a carbon tax regime, for which legal framework exists only up to the national level.
In the US, my gut feeling about the politics of each would be that the tax would probably be harder to implement than the trading scheme–even in this recessionary environment which has somewhat tarnished the halo of the free market. “Tax” is never popular here, either as noun or as verb.
(And indeed, I suspect that some of the “skeptic” bashing of cap-and-trade may be motivated by strategic thinking along those lines: “Get the environmentalists lined up behind the measure less likely to pass, and maybe we can go with BAU that much longer.”)
#43. In the medical literature there has been a trend towards publishing short commentaries on studies that emphasize the quality of evidence, i.e. the “evidence-based medicine” movement. For an example, see a recent issue of Evidence-based Dentistry:
http://www.sciencedirect.com/science/journal/15323382
Here, the goal is to get clinical findings to practicing dentists.
I can envision a market for “evidence based climate change” and would encourage some strapping young investigator to start one. Unlike in evidence-based medicine, there is no clear “end user” for climate science. I would like to think that it is journalists, policy-makers, and the general public, but most seemed too trapped in their own paradigms.
MJ asks “How do me make legitimate climate science more accessible?”
The problem is the denialists. Give a simple explanation, they say it’s too simple. Give a more complicated one and you either have it still too simple, left out “something important” or have put it outside the accessible realm of the man-in-the-street.
The FAQ has links for just such an accessible resource on climate change and the science. Doesn’t seem to get any press time, though. Why? Interference.
#54
Well, I think the problem is sensationalism on both sides. Unfortunately, it seems the only way to gather the attention is to respond in a sensationalist way.
I agree the RC FAQ is one approach to help, but we need more. Climate change is a very complex issue for the scientist studying it, and an equally complex challenge in dealing with for policy makers, economists, etc. This broad interdisciplinary mix makes taking an issue and working towards solutions on a global scale that much more difficult. It is also a very unique issue in the time scales that must be considered. All these difficulties make informing the masses correctly and shaping policy wisely difficult. Reality is the whole world is not going to count on RC for their answers, so we need a broader reach through more channels.
MJ says “Well, I think the problem is sensationalism on both sides. Unfortunately, it seems the only way to gather the attention is to respond in a sensationalist way.”
Why do you think it both sides?
One side has “You can’t use radiative balance in working out the earth’s temperature because convection and conduction are far more important” and the other side has “If it weren’t for water, CO2 et al, we’d be on an iceball earth. And we’re adding more blankets”.
And when one side has “YOU’LL SEND US ALL TO THE STONE AGE!!!!!!!!” you think “It could get 6C hotter” is equally sensationalist???
You have a severe problem in your balance.
One article I read the other day on this subject put this dimming into perspective. It said the dimming effect is like reducing the output of a 100 watt lightbulb to 99 watts. That’s 1%. Compare that to the variability of the sun’s output over its 11 year cycle, of 0.1%. So the dimming is now very significant, isn’t it? Ten to one.
Ike Solem …
I thought I made it clear I was just quoting the opinion of the FSU grad student Tim was referring to.
I thought I was just making it clear that Tim’s interpretation of the FSU’s grad student’s post at CA that it “contradicted AGW” was false, and that this FSU grad student no where claimed that La Niña or El Niño “proves AGW wrong”.
I have not commented on cap and trade. I was simply trying to make it clear to Tim that he had misread the FSU’s student’s conclusions as “contradicting AGW”, which they don’t.
Because
1. The earth is not flat, to debate this would be stupid.
2. The earth is older than 6,000 years old, those who claim that we should debate this, such as those at Answers in Genesis, are stupid.
3. CO2, without doubt, warms the planet. To argue it doesn’t, as some denialists do, is stupid.
Which of these three statements do you disagree with? Which of these three are worthy of “scientific debate”?
As far as making climate science more accessible, the problem is biased coverage in the U.S. press – which is why you get 99% agreement among climate scientists on the basic issues of fossil fuels, deforestation, atmospheric CO2 and global warming, but only half the public shares that view. That’s because the U.S. press has for the past two decades insisted on giving “equal time” to a small number of industry-funded spokespeople, without reservations or qualifications – and it’s not just the George Wills and Heritage Institutes, it’s really seen across the entire spectrum of U.S. media coverage.
Jon Stewart said this about reporters in finance:
“STEWART: Yeah. I’m under the assumption, and maybe this is purely ridiculous, but I’m under the assumption that you don’t just take their word for it at face value. That you actually then go around and try and figure it out. So again, you now have become the face of this and that is incredibly unfortunate.”
That doesn’t just apply to financial news reporting.
An example is Dr. Don Easterbrook’s Letter to Andy Revkin, New York Times Story, posted courtesy of ICECAP, one more in the train of secretly financed front groups for the fossil fuel lobby. In that case, Joseph D’Aleo is one who set up ICECAP, and you can also see him being lauded over at Pielke’s site. The problem is not these denialist setups, really – it’s the fact that they’re given a platform by media organizations.
I find Dhogaza’s statement 3 “CO2, without doubt, warms the planet. To argue it doesn’t, as some denialists do, is stupid” rather curious because I thought it now agreed that 380 ppm would not be enough unless there was a concomitant effect involving water vapour. Is this climate science or political invective?
Sorry to be off topic but can someone help me counter this from a skeptic website
”As we can see above, carbon dioxide absorbs infrared radiation (IR) in only three narrow bands of frequencies, which correspond to wavelengths of 2.7, 4.3 and 15 micrometers (µm), respectively. The percentage absorption of all three lines combined can be very generously estimated at about 8% of the whole IR spectrum, which means that 92% of the “heat” passes right through without being absorbed by CO2.”
“truth” – such a modest name – (comment 50) shouldn’t be so lazy. Instead of slagging off George Monbiot as a hysteric throwing unnecessary “hissy fits” over climate change, and in the meantime neglecting the destruction of the Amazon, he (she?) could have looked up Monbiot’s very precise record on the Amazon. It is superb, and encompasses a narrow escape from death at the hands of a gun-wielding thug – in the Amazon. Look it up Mr/Mrs/Miss/Ms “truth”, and report back to RealClimate, pronto! And get real on climate too!
Mike
It’s encouraging to see articles and studies appearing about what we used to call pollution (so2, NOx, O3,soot,etc.). This evidently still-dangerous current threat may have been pushed to the back by the future threat of co2.
I believe there is a good chance China and India will attack their conventional pollution problem using long-proven technology that does a good job on everything except co2 before turning to co2. Maybe they can do both.
re Derek #60, you thought wrong. Don’t even know where you’d get that from either.
There isn’t enough change in CO2 forcing to account for the observed change, even at a level of 380ppm, but that along with the various positive and negative feedbacks known is.
It isn’t what you said. Did you just make that up?
If the amount of CO2 in the atmosphere were diminished to 0 ppm – all CO2 removed – the planet would cool. CO2 is known to be a GHG. There’s no scientific disagreement over this fact.
ziff, why?
Just ask yourself 8% makes WHAT difference to things. If I were to add 8% arsenic to your teaspoon of sugar, you’d be on your back, doing the dying fly in seconds.
What is it that you think needs debunked? There’s nothing there TO debunk.
E.g. if we were 8% warmer, we’d have to add ~24C to the earth’s temperature. then again, your query doesn’t say what that 8% is supposed to mean.
dhogaza old chap, there’s no argument about CO2 being a greenhouse gas, the argument is to what extent it’s current levels are contributing to our climate, both past, present & future.
A straight plot of “temperature” against “CO2 levels” isn’t a straight line, as I’m sure you’re aware.
The relationship is poor, hence the need to add “forcings” by other atmospheric components.
It’s these “forcings” where debate lies, the question about past temperatures & what proxies we can use to assess these and their accuracy, how accurate measurments are from the “scientific era”, the effect of urbanisation on temperatures and, of course, exactly how accurate climate models are, seeing as their predictions are extremely wide.
I also fail to see why Gore’s statements, as published in today’s Guardian, compared to the last few year’s polar ice data, are OT, compared to many other comments here.
Ziff house — I’d suggest since you’re not ready to “argue” at that skeptic website, on this basic question, you might want to back off a while, read the Start Here links and the first link under Science, get familiar with the background.
It sounds like someone has made up some numbers, then applied the made-up numbers as a percentage and claimed to have refuted the observed facts. This kind of argument is often pointless to join.
You could point to a picture:
http://www.ssec.wisc.edu/gifts/science/slideshow/images//Slide4.JPG
You could point out that the energy of a photon depends on the wavelength, so the amount of energy absorbed is not a simple percentage of all photons; it depends which ones. You know how to find that.
You could point out the difference between incoming and outgoing. You know how to find that.
Once you can point to the science — rather than try retyping it — you may find it more useful to respond. Or maybe not.
My opinion: there are far more septic websites than there are people who understand even basic physics. Most of them are worth leaving to fulminate.
Coming to RC and asking for some single tidbit amounts to trying to educate a broad misunderstanding by arguing points, without foundation. That isn’t likely to do more than “teach the controversy.”
ziff house #61, an invaluable learning resource is David Archer’s interactive MODTRAN model:
http://forecast.uchicago.edu/Projects/modtran.orig.html
What matters is not how much or how little of the outgoing heat is absorbed by CO2, but how much that changes as the concentration changes.
Set all other gases, and water vapour, to 0, and do the calculation for CO2 = 375 ppmv. You see that 355.762 watts per square m is coming out of the top of the atmosphere.
Then, repeat the calculation with CO2 = 750 ppmv. No you see that only 351.366 W/m^2 comes out. Difference: 4.4 W/m^2.
Now you want to know how the temperature on the ground changes. That’s simple: add temperature to the “Ground T offset, C” field. If you enter 1.1, you’ll see that balance is restored, again 355.762 W/m^2 coming out. That’s 1.1 degrees C for the doubling sensitivity for CO2 only, a well known value. On top of that come all the feedbacks, water vapour the biggest of them.
Have a look at the CO2 absorption spectrum: effectively you only have to look at the 15 µm = 666 cm^-1 band, which is very broad, and saturated in the middle, i.e., there you’re looking at the top of the atmosphere where temperature is around 220K (this is for the tropical atmosphere).
What happens when you double CO2 is that the “flanks” of this inverted trapezoid move outward from the band centre. That’s what causes the CO2 part of the greenhouse effect.
As for the 92% that “passes right through”, no it doesn’t. That’s what the water vapour is for ;-)
BTW if you want to give your favourite “skeptic” a puzzle to chew on, point out the narrow upward spike in the middle of the 15 µm band, which gets more pronounced as you increase CO2. This is the stratospheric warming signature, a very specific fingerprint of a greenhouse gas transitioning from opacity to transparency at altitudes where the temperature gradient is positive with height.
Rub it in.
Oh, for “ziff house” — here’s your problem. One good way to check what you’re arguing with is just to paste their stuff into Google. I tried that with your quote.
That bit appears on 746 English web pages, according to Google. See if the original source has been debunked, if you want to pursue it; if it has, point to that.
Re Derek @60: What Dhogaza wrote, namely “CO2, without doubt, warms the planet. To argue it doesn’t, as some denialists do, is stupid” is in no way in conflict with the additional feedback warming that water vapour subsequently adds.
In fact, it is the warming provided by increasing CO2 that allows the atmosphere to hold more water vapour.
Dhogaza is entirely correct: that argument is stupid.
ziff, if they’re honestly trying to claim that CO2 only absorbs at 3 discrete frequencies, they’re full of it. Check http://www.giss.nasa.gov/research/briefs/ma_01/
Here’s a quote:
“The spectrum of heat absorption by Earth’s atmosphere contains hundreds of thousands of absorption “lines”. For carbon dioxide alone there are over sixty thousand lines.”
Ziff, it looks to me that your interlocutor is handing you the gun to shoot him in the foot. You could ask him as a follow up question what would happen if that 92% failed to escape.
ziff, another source, if you need one (although the strategy of pointing to the debunking of the original argument is always fun). This is a graph of absorption spectra of various atmospheric components: http://www.iitap.iastate.edu/gccourse/forcing/images/image7.gif
…which is a part of this short online course, which has some nice references, even where they get their formulas and so on. Not real slick to look at, but good info. http://www.iitap.iastate.edu/gccourse/forcing/forcing_lecture_sec.html
Adam, it’s easy to find denialists who deny that CO2 is a greenhouse gas.
I’ve tried posting a link to such a claim, but the spam filter here keeps rejecting it, but you can find such claims yourself in google.
Ziff #61,
There is a two-part post on RC debunking a different but related argument (CO2 absorption band saturation). Reading it will not give you a snappy rejoinder, but you can learn a great deal about the science underlying your question. It’s good background for understanding the explanation Martin Vermeer gives in #69.
https://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument
https://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument-part-ii/
Everybody, thank you for your responses. Boy oh boy, i can see the of problem trying to convince people is long and difficult.
Martin Vemeer says: “BTW if you want to give your favourite “skeptic” a puzzle to chew on, point out the narrow upward spike in the middle of the 15 µm band, which gets more pronounced as you increase CO2. This is the stratospheric warming signature… Rub it in.”
If you suspected that is complete nonsense, you are correct. Take a look at the following RealClimate post and links therein:
https://www.realclimate.org/index.php/archives/2006/11/the-sky-is-falling/
For more background: http://www.atmosphere.mpg.de/enid/20c.html
Second, it is not the “outgoing heat” that is absorbed and re-radiated by CO2, CH4, N2O, CFCs, and H2O – it is the infrared radiation – those gases are mostly transparent to visible radiation.
As others note, the increase in atmospheric CO2 due to fossil fuels and deforestation warms the troposphere but cools the stratosphere – think of a cold blanket; you wrap it around yourself, and you get warmer, but to a distant observer looking in the IR region, you’ve suddenly cooled off.
The aerosols over China and India complicate the picture – are they warming the lower atmosphere while also cooling the surface? What is the role of visible radiation absorption & scattering vs. the role of infrared radiation absorption by aerosols? How does China’s aerosol pollution influence the drought situation in northwest China? How does the ABC influence temperatures across the Indian subcontinent and the Indian Ocean? Those are the real issues related to this, which are actively being studied.
Maya (72), in your answer to ziff you are terribly misreading or misrepresenting the “discrete” and narrow nature of the CO2 absorption bands.
Ok so its the upper atmosphere CO2 thats imporatant, i understood there was very little mixing above the tropopause. Don’t get me wrong here, i’m not trying to debunk
Ziff, Two homilies:
A man cannot be reasoned out of an opinion into which he was not reasoned to begin with.–Anon
Never teach a pig to sing. It doesn’t work, and it annoys the pig.–Mark Twain
I fear the best you can hope for is a vivid demonstration that your correspondent is full of fetid dingo’s kidneys.
Martin(69): “David Archer’s interactive MODTRAN model: …Set all other gases, and water vapour, to 0, and do the calculation for CO2 = 375 ppmv. You see that 355.762 watts per square m is coming out of the top of the atmosphere.
Then, repeat the calculation with CO2 = 750 ppmv. No you see that only 351.366 W/m^2 comes out. Difference: 4.4 W/m^2.”
While I had looked at David’s model before, I had not tried that exercise. I wondered how much effect your setting other gases to 0 had, so I tried it using the defaults at mid-latitude summer. Now the difference for doubling CO2 is only 2.86 W/m^2. Even more interesting, the ground offset to recover the original Iout is just 0.85 degrees for constant water vapor, and 1.26 degrees for constant relative humidity.
Maybe I made an error (please point it out if so), but I’m surprised the water vapor positive feedback is so small. Those other much more poorly understood feedback effects must be very large!
Rod B, I really wasn’t sure what they (whoever ziff is quoting) were trying to say – it seemed to be self-contradictory, or at least incomplete. To try and figure out the question, I went and looked up information about the absorption spectrum of CO2, from which I posted the link(s) to the further information. ziff’s post refers to bands, but cites 3 specific wavelengths, and a band would be a range of wavelengths, not a specific one. Um, right? I barely even remember having had optics in physics, much less any of the terminology, so if I’ve got that completely wrong, please explain!
Another new study stating that “global warming has been proven false” has been released. It’s already hitting blogs. Hold on to your hats. Tsonis at the University of Wisconsin-Milwaukee.
http://www.allheadlinenews.com/articles/7014437410
[Response: I guarantee that few of the people quoting this study have even read the abstract, let alone the paper, and have absolutely no idea what is being discussed. A quick read is sufficient to discover that a) this is a discussion about how the climate reacts to forcings, not whether it does, and b) doesn’t look at GCM output (and so can’t really assess whether GCMs are in some way deficient), and c) explicitly states that the authors expect the long term trends to continue to warm. How this supports the idea that GW is false is completely beyond my ken. It proves rather (once again) that there are plenty of people who can type faster than they think. – gavin]
> it is not the “outgoing heat” that is absorbed
> and re-radiated by CO2, CH4, N2O, CFCs, and H2O –
> it is the infrared radiation
Outgoing heat = infrared. Same thing.
> – those gases are mostly transparent
> to visible radiation.
True that. Transparent in the visible and soft UV range where most of the sunlight energy comes in.
Rod, Maya’s not misrepresenting anything. That’s a direct quote from the source, accompanying the illustration. Seriously, man, read what you’re criticizing, would you please? At least now after the fact; preferably before.
A slightly longer excerpt from Maya’s source:
“… Because carbon dioxide can drive climate change, it is important to be able to accurately determine its heat absorption characteristics. The spectrum of heat absorption by Earth’s atmosphere contains hundreds of thousands of absorption “lines”. For carbon dioxide alone there are over sixty thousand lines. In order to model the absorption spectrum of CO2, we need to know the spectral location (wavelength), the strength, and also the shape of each line….”
Rod, you may not like a vague feeling you get reading this, but it’s silly to attack Maya for how you feel.
Consider the feeling may be telling you something about reality — something that you find uncomfortable — and that’s the important lesson for you about this.
Then read the actual source text. Bite the bullet.
Here is the article from which that quote came so you may see it in context. http://www.middlebury.net/op-ed/global-warming-01.html
My apologies for posting this rubbish. So why did i quote it? I hadn’t seen an attack on the basic premise before and had no idea how to respond.
Ziff house, the critical info at that site is the “bio” of the editor:
http://www.middlebury.net/op-ed/global-warming-01.html#bio
So, given that information, try this search:
http://www.google.com/search?q=modulated+%2Bpeden+beam+quadrupole+mass+spectrometer
I suggest reading the first hit, at Rabett’s place, for background.
Some battles are worthwhile. Choose yours carefully.
I guess that this all belongs in the ‘new blogger’ advice column.
I took a quick read of the original paper (draft) posted by Gavin just above which is purportedly in contradiction with AGW. My take is that it is a statistical analysis showing that long term trends in temperature (upwards) include periods of stasis or even decline. Rather than being contrary to AGW, it is just talking about something that we already know, perhaps in more precise stastical terms–that we are not seeing an annual warming proportional to the annual increase in CO2, nor is there simple uncorrelated (between years) random variability with an upside bias. Rather, there are periods as long as a decade when temperatures can be stable or even declining superimposed on a longer upward trend. These medium term periods of stasis will make political action more difficult (my conclusion), but I am sure that the authors would agree with Gavin that there is no contradiction at all with AGW. At least, they are not concluding anything that conflicts with AGW.
Maya (83), no, your description here is accurate. I was merely quibbling with your emphasis in (72), responding to ziff’s query about “…three narrow bands of frequencies…” with “…they’re full of it…” and citing jillions of frequencies that, at first glance, would lead one to think it almost a continuous spectrum of absorption. I think it was too much hyperbole (Hank’s rousing defense not withstanding), though your referenced graphs could have corrected that notion.
A classic essay is The Waking Up Syndrome
by Sarah Anne Edwards and Linda Buzzell
http://www.hopedance.org/cms/index.php?option=com_content&task=view&id=413&Itemid=32
My comment #43, MJ #47. I am an American professor on sabbatical in The Netherlands and working long hours in the lab. I can only rarely comment on posts in a timely manner due to the time differences. Yes, I agree that it’s difficult for a scientist to keep up with the literature even in a relatively narrow corner of his or her specialty and I don’t see anyway around this. My point is that the real scientific debates that place in the scientific literature, with only very informal debates at scientific meetings and perhaps by email. Postings in blogs hardly ever matter, unless they are followed up by a publication in a scientific journal. As someone who does a lot of work as an editor and reviewer, I would say that competent reviewers need to be familiar with at least a significant portion of the citations found in a manuscript and that this familiarity is largely limited to active researchers in a relatively narrow field. I don’t see anyway of getting around that. One the other hand, since modern research often has a strong interdisciplinary component, it’s not unusual for the authors of scientific papers to make mistakes when they go outside their conceptual framework. As an ecologist who works on lake food chains, I occasionally review papers and grant proposals by biological oceanographers that reflect weaknesses among a large part of this group in understanding ecological and evolutionary theory. If one is not familiar with the literature cited in a manuscript, one can read it competently if one is familiar with the appropriate research tools, such as statistics, experimental design and/or computer modeling. I would rate myself able as well qualified to read articles about ecological aspects of climate change, but only qualified to review such articles dealing aquatic food chains. Since I am now very interested in climate change, I may occasionally read papers on physical modeling but I have to admit that I would need to spend great amounts of time that I don’t have to be able to criticize or contribute to a debate on such approaches. I have to assume that peer reviewed papers are building on previous studies and a critical but valid way.
ziff (#87) – I have had the misfortune to stumble across this rubbish myself.
It contains the most incredible statement: “Curiously enough, the UN IPCC reports don’t even mention water vapor, since it is technically not a ‘gas’ in the atmosphere.”
Using the search function in Acrobat Viewer, I started counting the references to water vapor (or vapour) in the 4th IPCC report and lost count at around 200.
I pointed this out to the author and he tried to fob me off by claiming he meant “IPCC models.. do not include any consideration of H2O in cloud formations”, which was (whether or not it is actually true!) clearly not the context of the claim.
The only interesting thing about the piece is why someone would write it, but that is a question of psychology, not of climate science.
Ike Solem #78: what you write (quote) is all true, but beside the point… my argument was about the CO2 spectrum in the context of David Archer’s simulator.
Steve Reynolds #82: Yes, I remember going through the exactly same exercise some time ago, and wondering how low these values were. And not only at mid-latitude; at all latitudes, and changing cloud cover doesn’t make a difference either.
“All models are wrong. Some models are useful.” I don’t know what’s wrong with this model, but these numbers are unrealistic. (Realistic numbers would be 1.1 degree for CO2 only, and 0.8 on top of that for H2O. The balance to 3 degrees is complicated, but IIUC cloud cover makes up much of it.)
Note that the model makes a number of approximations, e.g., that the vertical temperature profile is fixed, when in reality it changes when water vapour changes.
Note (2) also (looking at the lower graph) that CO2 increases strongly to 15 km altitude. Now I know that it increases a bit, but not that much. Makes one wonder.
Note (3): look here. Note (slide 15-17) that the author happily critches up the water vapour scale to 10… WTF? So “1” doesn’t mean “saturated”? Note also slide 7, showing an empirical counterpart to Archer’s model plots.
ziff house #87: don’t apologise. You created a learning experience for all of us ;-)
“So why did i quote it? I hadn’t seen an attack on the basic premise before and had no idea how to respond.”
Ask yourself first: is this worth responding to?
#92
Bill, thanks for your follow up and your comments are in line with what I see as part of the challenge. You and I who work in the sciences have a hard time just keeping up with our areas of expertise. However, the issue of climate change has implications on a global scale and for people of varied backgrounds. Just like you and I, most of these folks spend long days working, caring for family, etc. that don’t allow them time to delve into peer reviewed literature (that btw is not always easily accessible). This is combined with the fact that the majority of the population does not have the relevant background and experience to fully and accurately absorb the implications of the findings in a peer reviewed paper.
So, reality is we need other avenues, like RC and other blogs, but also other channels that reach the masses to provide accurate information in language and formats accessible to a wide range of folks outside the climate science researcher arena to drive wise response amongst people and their governments. Not an easy task.
On postings #20, #35, #36, #37, #45 and #48:
I listed (or mis-listed?) “major” contributors to evolutionary theory only to make the point that no one can plausibly claim to have refuted evolution without even mentioning their names, works or concepts, yet this is precisely what Marshall Institute and Heartland Institute “experts” have done against manmade global warming theory.
Personally I will probably never “get over” my impression that The Selfish Gene and The Extended Phenotype together constitute a major contribution even though they “merely” synthesize the original (and therefore “more” major?) work of other scientists. Your value judgment that I should have omitted Dawkins and/or included Hamilton instead may well be correct, but I did not regard or intend my list as definitive.
As for whether Dawkins and the scientists whose work he synthesized made a good case for gene selection, I deliberately named in my list, ad hoc though it were, such rival theorists as Gould and Margulis who are more appreciated by critics of gene selection. By dropping famous names on every side, I was hoping to side-step that debate. I still step aside from it now.
Until climate-science notables like Tyndall, Milankovitch, Arrhenius, Plass, Revelle, Keeling, Matanabe and the rest achieve some significant fraction of the fame or notoriety that accrues to notables in evolutionary biology, dishonest propagandists will continue to “get away with” claiming to have refuted manmade global warming theory even when they have not bothered to mention the names, works or concepts of leading climate scientists.
Martin#94: “Realistic numbers would be 1.1 degree for CO2 only, and 0.8 on top of that for H2O.”
I thought that this calculation was the one part of climate modeling that was well understood. Can gavin or david help here to explain why david’s model says CO2 doubling direct sensitivity is 0.85 degrees for constant water vapor, and 1.26 degrees for constant relative humidity.
Rod, seriously, this is one of the clearest examples recently of how what’s in your head interferes with reading the science.
> citing jillions of frequencies that, at first glance, would lead
> one to think it almost a continuous spectrum of absorption.
No. You take a specific count and turn it into ‘jillions’ — whatever that means to you. And then you paint that with the notion of ‘continuous’ absorbtion, the bogus claim about saturation.
Seriously, man, step back and look at the interference going on between the published science and the emotional weight you’re grafting on. It’s clearly interfering with your ability to read and think, it’s come to the surface here, you have made a lot of progress by asking good questions in between these episodes.
You’ve almost got it.
Catch these eruptions before they obscure your understanding and you’ll be able to read the science without immediately fooling yourself and blaming it on other people.
Look, we _all_ do this kind of thing, it’s normal human behavior.
But science is about how to _catch_ ourselves and one another to get past this kind of self-fooling.
#93 Garry S-J
I googled: ipcc.ch wator vapor
second link
http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter8.pdf
Send that to the author you mentioned who claimed:
The name of the chapter is
It contains such crazy statements such as:
It is loaded with info on clouds, and water vapor, and modeling, and precipitation, and, and, and…