Wednesday, August 09, 2006

Aged skeptics

I've noticed a pattern recently. Some of the most vociferous skeptics of AGW are professors emeritus. No doubt, some people will argue that these are the most trustworthy sources, since their career is over and they are not dependent on getting funding.

However, I will advance a second theory. I was at a meeting a few weeks ago where I ran into Bill Gray, a famous emeritus skeptic. He gave his standard stump speech in which he claims that the water vapor feedback is negative. I followed up on this with him and it became quite clear to me that he is unfamiliar with all of the peer-reviewed literature on this subject that has been published in the last five years. This makes sense. Reading the literature is a difficult and full-time job, and emeritus faculty simply don't need to do that. Especially (in the case of Gray) when your time is occupied being interviewed and screaming at people. As a result, my sense is that the views of emeritus skeptics are often substantially out of date.

But the story goes on. After arguing with him for a few minutes, it became clear that Bill Gray has no scientific theory of his own *why* the water vapor feedback is negative, and no data to support his non-theory. He has no manuscript describing his non-theory and no plans to attempt to publish it. After I pointed out all of the evidence supporting a positive feedback, he looked confused and finally said, "OK, maybe the feedback isn't negative, maybe it's neutral. I'll give you that." I quickly concluded that he has no idea what he's talking about. I wish everyone that considers him credible could have witnessed this exchange.

Thus, we have two explanations for the emeritus-skeptic phenomenon: 1) only they are credible because their career is over, vs. 2) their knowledge is substantially out-of-date. My personal experience is that the second explains the phenomenon far better than the first.

And anyone with additional theories, please leave a comment.

My point is not that all emeritus are out of touch with the scientific literature. Some continue to be extremely credible (anyone swinging at that strawman will have their comment unceremoniously dumped into the electronic ether). My point is that we have to consider whether any particular emeritus scientific (either pro or con AGW) is familiar with the most current science. If their knowledge is 10-years old, then their statements might be quite incorrect.

52 comments:

Anonymous said...

Dr. Dessler, it is obvious that if a scientist, no matter how old, is not educated or trained in a particular field, when it comes to specific scientific data and distinctions of that field, they are not experts to discuss it. However, if people think Al Gore or Tom Brocaw are qualified to speak on AGW, then I find it hard to believe they would think Dr. Gray is not. The specific example you cite about water vapor causing negative feedbacks is a complex one, do you actually believe the science is settled on that with no other possible interpretations of the phenomena? If so, then perhaps Dr. Gray is out of date and wrong. But does that make him also wrong on his view of AGW? I think you are carrying the credibility too far in that case. Even if you were the Galileo of water vapor, that wouldn't necessarily make you right on AGW. I like older profs (maybe because I are one) who have retired since, like Dr. Bohren (in contrast to Dr. Alley from PSU), many have no horse in this race and are likely to be objective, vs. people pushing books, publish or perish tenure and citation metrics, or actual cash from political causes like Dr. Hansen. The motives behind the words and the world view of the writer or researcher is very important in my mind, it tends to color the nuances and editorial comments around what their research says. Sometimes, far beyond what their research says, and there are many examples in the peer reviewed literature of that editorialization and comment.

Anonymous said...

Actually I would be happy to see the alleged dr.j provide some bona fides to back up the climate expertise he claims. Some of the things he's said make me, um, skeptical. In fact, for a paleoclimate guy to not be following the rest of the science to the point where he's unclear about positive WV feedback seems more than passing strange. Also strange is his apparent lack of information about Gray's laughingstock "THC drives a natural climate cycle" idea.

Regarding Bohren, I'm confident that only a handful of readers will have gotten to the end of that rant, so I'm not too worried about its impact.

Anonymous said...

Ah, so there are AGW believers who are capable of being skeptics of things they disagree with, now that is progress I guess. dano, the evidence of Dr. Hansen's "awards" are public domain and if you google you can easily find them. Perhaps you think some scientists and profs are so well paid that they would never think of profit from a book, or getting a promotion for grants and articles written and are motivated only by pure science and the joy of educating students, if so I have a bridge for you. Perhaps Dr. Dessler can give us some insights on that in a large, state university to augment your knowledge, I am already quite familiar with it. I can't find Dr. Dessler's pentultimate sentence, but I assumed when he said: "I quickly concluded that he has no idea what he's talking about. I wish everyone that considers him credible could have witnessed this exchange.", that he was talking about Dr. Gray as a skeptic of AGW, not as an expert on water vapour. If he was refering to water vapour expertise I aplogise for my misreading it.

I was not saying I think water vapour and cloud feedback as only positive is wrong, computer climate modeling it is not my expertise, paleoclimatology and stable isotope geochemistry is, but back when I took climatology classes in grad school and as recently as a few years ago, I heard scientists say that the feedbacks could be and are negative and positive. Now if the science is suddenly settled and this is a fact and not theory anymore about only positive feedbacks (I call them forcings, but that is my old fashioned way)then I was asking an expert about it, Dr. Dessler. dano you seem to be too, so is that a scientific fact now?
Mr. Bloom, what kind of bona fides are you speaking of? Do you want copies of my diplomas, testimonies from my high school teachers, recent check stubs, a transcript perhaps? And for what purpose, it is obvious you think Dr. Bohren's a nut of some kind and not credible, so why would you feel any other way about me if I produced all my records which would not be as impressive as his or Dr. Lindzen's? I find people who believe in AGW usually never consider skeptics credible regardless of credentials, so it would seem to be a waste of time to try and impress you. What is your claim to fame and academic pedigree? I don't need bona fides, I trust you.

Anonymous said...
This comment has been removed by a blog administrator.
Anonymous said...

dano is that somehow different from, say, the Ford Foundation grant wagon?

As an independent observer, let me state unequivocally that those types of attacks on people don't make anybody involved in the scientific debate look good ...

Andrew Dessler said...

Dr. J-

You asked whether I thought the science of the water vapor feedback is settled. Let me put it this way: in the last 5 years, there have been several different analyses that have all shown (using a diverse set of data and methods) that the water vapor feedback is strongly positive. There have been ZERO peer-reviewed papers arguing otherwise. The last paper to argue a negative feedback, Lindzen's Iris, has been pretty clearly rejected by the community after subsequent testing was unable to verify it. Thus, I conclude that it's pretty much game over for the negative feedbackers.

If you listen to a Bill Gray talk on AGW, he rails against models because (he claims) they get the sign of the water vapor feedback wrong. He doesn't have any other reason, so far as I can tell. So if you reject his views on the water feedback, then his arguments against AGW also don't have a leg to stand on.

Thanks for your interesting comments.

Regards.

EliRabett said...

I have a different take on this. I think, as many at the turn of the century the emeriti are not capable of the necessary conceptualization.
http://rabett.blogspot.com/2006/08/gone-emeritus.html

By the way, RP Sr. is running a series on golden oldies

http://rabett.blogspot.com/2006/08/another-one-gone-emeritus.html

Anonymous said...

Thank you Dr. D, I am not an expert on Dr. Gray and all his reasons for being an AGW skeptic, I can understand your reasoning, but could it be that Dr. Gray has other reasons to be skeptical? Water vapour has never been a big issue for me, but I am not a computer climate modeler who depends on it, I see many other lines of problems with AGW, perhaps Dr. Gray also has broader knowledge and expertise than you suspect, just MHO.

High regards,

Andrew Dessler said...

Dr. J-

With regards to Bill Gray, all I can go on is what he says. He very well might have other reasons, but his main argument is the water vapor feedback, and it's the only reason he talked about at this meeting.

Regards.

EliRabett said...

Sorry Dr. J. water vapor feedbacks are the ballgame.

Anonymous said...

elirabett, interesting theory you have, so water vapour is the only thing we need to study to understand climate change? Now that is simplification of complex scientific phenomena to the max. Have you contributed to IPCC and told them? They would love a single element correlation proving attribution, and you could be famous. I look forward to your paper on this.

Anonymous said...

OK dano, since you can't or won't google it, here is one of the articles:
http://www.newsmax.com/archives/ic/2006/3/23/112725.shtml

There are more on this, it was quite a stink during the last presidential election as Dr. Hansen was publicly endorsing Kerry during some of his NASA scientific speeches. Guess you were out of the country?

Anonymous said...

I'm sorry dano, it's not possible to have a civil conversation or scientific debate with you, partly because you don't read what I say. I told you I never claimed "[WV feedback sign] science [isn't] settled on that with no other possible interpretations of the phenomen[on]. Those are your words, I was asking Dr. D a question (since I am not an expert on water vapour) which he has since answered well, so you either need a new set of eyes or you need to learn to comprehend text.

So attack the source and not the facts of the story on Dr. Hansen, typical I'm afraid. He took $250,000 from John Kerry's wife's foundation, fact, he endorsed Kerry publicly and actively for President and contributed to his campaign, fact, he endorsed and acted as a consultant on Gore's movie, fact. Obviously, the NYT would never comment on this since he is also one of their advisors. As I said, some make money off their AGW views and take political positions, to me that is reason to question their motives, to you it isn't I guess, fine, so just say, so what? I probably will not choose to answer you again if your tone doesn't change however, I find your personal attacks quite boresome.

Anonymous said...

dano, your rants are getting in the way of what has been an interesting discussion here of scientific issues between scientists.

There are laymen like myself reading this blog who came here to read the scientific discussion, rather than pointless KOS-type rants.

EliRabett said...

Darling Julius, you may have noticed the word FEEDBACK attached to the end of the words water vapor.

Water vapor FEEDBACK is a determining factors in climate sensitivity.

But Dear Julius feedbacks need drivers. GHG forcing is the driver.

The greenhouse gas forcing is amplified by the positive water vapor FEEDBACK.

Got that now? Oh I suppose with a little more purposeful obtuseness you can come up with something.

Anonymous said...

tyler5, I think you can see the level of social development and intelliegnce we are dealing with here.
Regards.

Anonymous said...

True Dr. J. and since this link in the fart tennis derby is pay only, one has to wonder if he is a shill for subscriptions, really!!

Anonymous said...

dano, I wonder why you're not able to grasp the fact that your so-called "point" is exactly what I was referring to as your rant?

sean d, let's try this game, you and dano go off somewhere and insult people your own age and IQ, here's a link:

http://corporate.disney.go.com/environmentality/index.html

Anonymous said...

I'm even more convinced that dr.j is no doctor. But anyway, for the record, Bill Gray hung by his own words:

1) On his GW theory: http://www.realclimate.org/index.php/archives/2006/04/gray-on-agw/ . As far as I can tell the water vapor stuff isn't central to his concept, but is thrown in as an attack on the GCMs.

2) On hurricane theory: http://www.eas.gatech.edu/research/candr.htm . Bill looks a bit rumpled by the end of this, Needless to say, Science declined to publish his comment.

Tell you what dr.j, since I respect the need of many people for internet anonymity, I'm not going to say that you're a fraud just because you refuse to out yourself. I also don't expect you to agree to Sean's contest since he announced in advance that it would have only one possible outcome. What I will ask instead, if Andrew will agree to host it, is that we have a little debate to see if you actually know much abour your claimed field of expertise. I believe you said you were a paleo guy, but was there a subspeciality? Anyway, all we need to do is agree to a time (this weekend?) and conduct in real time so I can be assured you're not running to look up answers in between. Actually I guess debate isn't fair, since really it'll be me asking you some questions to see if you have any idea what you're talking about. I would imagine 5 or 6 questions would do it, so it shouldn't take long.

Anonymous said...

dano, you are still playing here?

What happened, did the big kids scare you away at the Disney site?

And Mr. Bloom, so now it's to be an inquisition, is it, conducted by you?

Dr. Dessler, your colleagues here, if that is what they are, are a pack of juvenile thugs.

If what I have witnessed here is typical of the people in your science, then GW advocates have lost this debate already, as no one could take these guys seriously.

Anonymous said...

Well said tyler5, I think Mr. Bloom (who I have not seen any info on how qualified he is to argue pro-AGW issues, who I said I would trust with his credentials and educational background info, is trying to turn a blog for ideas and thoughts into some thesis exam. Really Dr. D, what kind of blog do you want here? This one is turning nasty and ridiculous, far beyond a true discussion on science and politics of this issue.

Sean d, here is one, since you seem to want to actually discuss rather than launch sophomoric personal attacks on those who disagree with you.
http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=6372425&query_id=0

But I can already predict, too old, I want something in the last 6 months, so here we go again, only new is valid, since I know little has been published lately.

Anonymous said...

dano, you do need to read more closely, I have considered clouds and water vapour to be the same, when I said this: " I was not saying I think water vapour and cloud feedback as only positive is wrong, computer climate modeling it is not my expertise, paleoclimatology and stable isotope geochemistry is,". Now , perhaps we have a failure to communicate, but since I first questioned Dr. D on this I have been consistent, and specific, in mentions of clouds and water vapour together, since of course they are one and the same in chemistry and physics of the atmosphere. If you or Dr. D wanted to seperate them as having different feedbacks and forcings, you should have done that. However, in the article that started all this a while back : http://www.gfdl.noaa.gov/reference/bibliography/2006/bjs0601.pdf
it is argued that clouds are also positive feedback and forcing, and that is really what I was questioning. So do you now admit that clouds are negative feedback and forcing or are you saying they are positive?

Perhaps you misunderstood, if so OK, but I do hope you weren't misreading it just to have an avenue to attack my credibility.

Anonymous said...

dano,

"ttyler, you haven't answered my questions from previous"

well, yes I did, Dano, you just don't grasp the answer ----

Anonymous said...

OK, you win folks. Classes start soon anyway, and this blog has failed miserably to meet my expectations for discourse and discussions, if I want to be chided for being old I can just listen to my college kids. I also think this blog has attracted almost all pro-AGW believers, by design I suspect, so having any kind of diverse, objective debate is impossible, I hope you all enjoy talking to each other and reinforcing each others biases, I have work to do, goodbye and good luck. Best,

Anonymous said...

dano,

You write to Dr. J,

"Actually, you are being chided for willfully obfuscating the comment thread and not grasping, well, anything that was brought up here."

Now dano, don't tell lies to your little friends.

It's not nice.

Anonymous said...

A capital idea Dr. J, this blog is dead in the water, as dano and his little buddy sean google things to put in and show pictures of cool planes, while accusing Dr. J of the very things they are doing by not reading what he says. If we are to believe their bios as bloggers, dano has no first hand credentials to question anyone on climate (you don't need a weatherman to tell which way the wind blows, as the old song goes)and the others have nothing at all yet accuse Dr. J of having no education or right to post. TTyler5, you may want to reconsider this blog too, you appear to be way too smart and perceptive to stay here.

Anonymous said...

dano, you are an urban eco sys consultant, for god's sake.

Who are you to lecture anyone on climate science ---

grow up, motor mouth ---

Anonymous said...

Yes, dano, that site is much more objective, open and adult than this one so far. And you actually proved my point so well there when I said : "It is even more powerfully clear when you see what the AGW believers are saying about it in the blogosphere. The personal ad hominem attacks and demonization of Dr. Bohren’s shows the importance and significance of his analysis and views."

I was actually talking about the left wing realclimate.org attacks on him, but yours are just as bad, and thank you for proving it. It might be al least amusing to monitor the rants and rambles here for a while.

Anonymous said...

Just curious Sean, you are very young, and working on a Ph.D., but you have very strong and seemingly set in concrete ideas on AGW, where does that come from?

Anonymous said...

sean d, thank you for stepping forward.

I am a layman and here to listen and learn, and I appreciate the attitdue you have expressed above.

Thanks!

Anonymous said...

OK, I have to say one last thing since Sean has been so forthcoming, mature, and civil. Sean, I don't know how many times and how many ways in how many blogs to say this again, but I AM NOT AN EXPERT ON WV OR CLOUDS. That is why I ask questions and ask for advice, and I didn't say I knew anything about it or had evidence of feedbacks of any kind. If asking questions get these kind of reactions, I just think this blog is doomed. And I have no interest in discussing WV or clouds anymore after my questions were answered by Dr. P and Dr. D, so even though I am leaving perhaps you all should move on past WV and get to some real issues, if so I could be back. Regards, Best, Peace.

Anonymous said...

sean d, again as a novice here --- someone Dr. Dessler would likely consider as being on the "climate science 101" level -- I can only say again that I am very very impressed with the history and depth of climate science.

I have been reading Spencer Weart's online version of "The Discovery of Global Warming" as well as working through basic classroom-level material avaliable online, and I was glad to learn after wasting so much time with the just idiotic "popular debate" going on in the media that this is really a very vast science based on many decades of research.

I am sure Dr. Dessler could name one in a heartbeat, but as an "outsider" yourself, is there a basic climate science classroom texbook you have come across that you would recommend?

Anonymous said...

Thank you Sean for an honest and straight forward answer. I am always curious where people get their views on this. My observations after many years of the subject is that yes, we know much scientifically about it, but even so there is more we don't know, and what we do know can be interpreted many different ways by reasonable and rational scientists, thus conflicting interpretations of common data, not uncommon in science but the foder of disagreements and arguments in public policy matters. I have come to a different conclusion than you, using different scientific data perhaps, but as Dr. Dessler says, perhaps there is also a value judgement involved here. Regards,

Anonymous said...

Actually the majority attribution factors and severity of GW are also somewhat value judgements in my mind, the value you place on the accuracy of the data in all the science disciplines that have skin in the game on climate change. But, yes Sean, I agree, at this point the skpetics and believers should come together on more politically neutral and common sense policy options where common ground exists regardless of what is causing the warming. Similar to what the waring factions of tropical storm experts did on hurricane policy options a few weeks ago. I think we scientists can get there if the politicians will let us.

Anonymous said...

sean d, thanks again. Found it:

http://www.atmos.washington.edu/~dennis/gpc.html

Here's the last part of that url in case it doesn't make it on the page:
/~dennis/gpc.html

Anonymous said...

sean d and others,

question for you here, if you don't mind taking questions from a novice.

Under current environmental policies here in the US, is CO2 scrubbed or cleaned in industrial processes, say in those processes covered in the GHG Inventory:

http://yosemite.epa.gov/oar/globalwarming.nsf
/content
/ResourceCenterPublicationsGHGEmissions.html

( I broke up the url to make sure it fit on this page)

I was under the impression that CO2 emissions are at least partly "cleaned up" by the processes used by industry to clean up other emissions, but several people have told me this is not neccessarily so.

EliRabett said...

Short answer is that CO2 is neither scrubbed nor recovered in any significant way in the US or else where at this time.

The volumes in the most important sources (fossil fuel energy generation, cement, aluminum, etc.) are daunting, and then you have the problem of where to put the stuff.

There are ideas out there, but no serious full scale demo.

That being said there are probably places where the CO2 is recovered for reuse such as chemical synthesis in supercritical CO2 (a really elegant system coming into more use for what is called green chemistry)

Anonymous said...

Ok, I found it, the key words are simultaneous reductions, GHGs and criteria air pollutants.

I am taking it that the existing simultaneous reduction levels from anti-pollution technologies which have this effect are not enough?

Anonymous said...

elirabbet, thanks, just caught your reply! Appreciate it much!

There is a well-known scientist who is working on plan to bury co2, you mightfind this interesting if you haven't seen it yet:

http://www.commondreams.org/
views06/0223-32.htm

(Again, I am breaking up the url's as they sem to run off the page quite a bit on these blogspot blogs)

EliRabett said...

Oh yeah. There are two ways to boil down links. The first is to go to www.tinyurl.com and get a short url to insert.

The second, which works with blogger and on most other sites now is to use html tags inserted into your message.

Ask your friendly guru, or look at the source code from this page.

EliRabett said...

On the question of text books, the problem is you need several:

One on atmospheric chemistry such as Wayne's Chemistry of Atmospheres or Brasseur, Orlando and Tyndall on Atmospheric Chemistry and Global Change

One on meteorology

One on climate

One on biogeochemistry

One on oceans

Anonymous said...

Elirabett, thanks for the advice on tinyurl, and for the suggestions on a study program.

I have school training in chem, bio, geo and geophysics, oceanography and of course astronomy and basic physics (and where the modelling is concerned I am an independent IT professional with a ten-banger beowulf here at home) so I'm not starting out with an entirely blank mind here, but meteorology and climate are definitely blank spots!

I am lucky enough to reside in the Clear Lake area of Houston and have not only the NASA resources and personell at my fingertips (JSC is only five minutes from here) but as well one of the biggest academic libraries in Texas at the UH main campus and a community ebook card at the local community college. The UH lib is a great repository of scientific journals both in the stacks and on the net. The Texas A&M Marine Bio unit at Galveston is also about a twenty minute drive south of here.

In other words, I have no excuse for not being familiar with the science already!

Thanks again for your help!

regards
ttyler5

Anonymous said...

Tyler5, there has been much work done on CO2 removal, sequestration, etc. This paper is a helpful summary: http://tinyurl.com/notbc
In most pilots, however, the costs were way too high to justify, many of the more sophisticated pilots have been done in Norway on offshore oil fields to try and remove CO2 from gas fired power plant emissions. There the government charges a hefty tax on CO2 emissions, so a possible economic case presented itself, but even the government decalred it too expensive for commercialization.

Anonymous said...

Here is the other one I spoke of, forgot to give the link:
http://tinyurl.com/gs5c6

Anonymous said...

Frankly you need other text books too, one on Historical Geology and one on Paleoclimatology.

Anonymous said...

Mr. Landis, Dr. J, thanks for the help, I am very appreciative!

I don't have a schedule that will allow me to take classes, so I must rely on personal contacts and the science community on the 'net for interaction and intellectual stimulation.

And from what I've seen, there's plenty of "intellectual stimulation" up here!! :^D :^D :^D

Anonymous said...

Sorry I am late to this discussion, but I have muddled all the way through and once again witnessed the AGW supporters mischaracterizing the argument and then claiming another victory. It is like watching Captain Ahab harpooning his own paper machete Moby Dick and then claiming to have killed the White Whale!

Here are a few things about AGW that skeptics do not and never have disputed:

1. Increasing atmospheric CO2 has a warming effect on the atmosphere.

2. All else being equal, increasing atmospheric temperatures promote increasing amounts of water vapor in the atmosphere, which is also a ‘greenhouse’ gas.

I, too, have heard Bill Gray speak about the water vapor loop being a net negative in man-made atmospheric warming, but he is not talking about the same thing as Dr. Dessler. Dr. D is talking about the specific process in which the decreasing vapor pressure in the warming atmosphere promotes additional evaporation and a net increase in water vapor. I don’t know of anyone, including Bill Gray who would argue that doesn’t happen in the real world. There is considerable debate over just how much water vapor will be added. There is also considerable debate about the assumption of constant relative humidity that is part of all the GCMs. I believe that Even Dr. Dessler’s own studies have indicated that the positive feedback of water vapor in the models is too high.

When Bill Gray speaks about a net negative or neutral forcing from water vapor, he is talking about the entire water cycle. Warmer temperatures may promote more evaporation, but that doesn’t just put more water vapor in the air. It changes lapse rates, cloud patterns, precipitation and so on. He argues that the net result of all of this may very well be a cooling that offsets some of the warming of CO2, and he has a good reason to think that way. Before you can understand his argument, however, one must step back from the details of the debate and look at one aspect of the evolution of climate science over the past 50 years.

For the most part, the study of climate has been one of pattern recognition. For climatologists like Bill Gray, recognizing the patterns comes first and understanding the physics behind the patterns is a distant second. This is certainly a valid way to develop an understanding of nature, for the patterns are reality. This is a top-down approach to understanding climate. One observes the whole system, noting how it functions, without any preconceived ideas about why it is doing what it is doing.

From his studies, Dr. Gray noted a cyclical pattern in Atlantic Hurricane Activity and became a public figure when he began forecasting the number of storms annually and warning all who would listen that hurricane frequency in the Atlantic Basin was due for a big increase in the 1990s. Using his method of pattern recognition, he accurately predicted this climate change; a strong validation for his scientific method.

At the same time, atmospheric scientists were harnessing the power of super-computers and finding success in developing integrated equations of specific processes taking place in the atmosphere. This is bottom-up approach to understanding the atmosphere. Instead of observing the whole and looking for patterns, individual processes are analyzed, quantified and then integrated into the whole.

And there’s the rub!

While we have developed an excellent understanding of many of the processes occurring in the atmosphere, and even some success in stringing several processes together, chaos theory tells us that any attempt to integrate all of the processes into an integrated, working model capable of mimicking climate and climate change into the future, is mathematically impossible! However, chaos theory does recognize pattern recognition as a mathematically viable way of determining the probabilities of a future state of a chaotic, complex, non-linear coupled system – like climate.

I know, I know! This is an old argument and usually dismissed with a wave of the hand, but never with a mathematically sound argument, in my opinion. But let’s get back to the issue at hand.

The majority of the climate community is now involved with trying to understand the individual processes that comprise the greater chaotic system known as climate, and then integrate them into a functioning model. Even though chaos theory suggests that this is a fruitless effort, it is considered by many to be the only legitimate game in town for understanding climate change. On the other hand, pattern recognition is considered old fashion, out-of-date, quant and simple. Prof. Gray is roundly criticized for not presenting the mathematical equations that describe the individual physical processes that make up his theory on climate change. Skeptics in general, are ridiculed for not presenting an alternative mathematical model to the consensus view, which indicates that AGW supporters are missing the whole point!

Why does Prof. Gray believe that the (entire) water vapor feedback loop is a net negative or neutral feedback? Because he can not find any evidence of a strong positive water vapor feedback in the observations of the climate system! To the AGW supporter this idea seems naïve at best, just plain stupid at worst. They say that individual equations prove it must be there, forgetting that the integration of individual processes into complex, coupled, non-linear chaotic systems don’t add up to what one would expect!

So let’s look at the numbers. Over the past 150 years, the concentration of atmospheric CO2 has increased by more than a third. It has been calculated that the forcing from a doubling of CO2 from pre-industrial levels, all else being equal, would deliver a warming of the average global temperature of 0.6 to 1.2 degrees C. Since the effect of increasing CO2 on temperature is logarithmic, it is estimated that more than half of this forcing (0.3 to 0.6 degrees) should have already occurred. Add the water vapor feedback and other positive feedbacks that the models suggest and we should have double to quadruple the CO2 forcing alone. That equates to a warming of 0.6 to 2.4 degrees.

The (disputed) estimates of global warming over the last 150 years generally come in around 0.7 degrees C. In order for the models to have any skill, the entire sum of this warming must be due to increasing CO2 and feedbacks alone. Other bottom-up researchers have concluded that additional forcers, including the sun and changes in albedo, account for more than half of this warming (at least)! It seems that the atmosphere is telling us one of two things. Either the net result of all the feedbacks is close to zero, or something else is preventing the warming.

Bill Gray (along with many others) believes the former is the case. The data tells us that the feedbacks are near zero, the overall forcing of a doubling of CO2 is probably less than one degree C, and the risk of an AGW climate crisis is negligible. Developing equations and then integrating them to show how the feedbacks are near zero, is not required to confirm that they are indeed near zero. Just look at the real world observations.

Of course, AGW supporters can not accept that the sum of their individual processes do not add up to crisis. They insist that something else is preventing the warming and the most likely culprit is more human pollution. They argue that aerosols have been blocking the amount of sunlight reaching the surface which produced cooling, until the Clean Air Act removed the aerosols and allowed the warming to commence. Once again, the Earth tells us that is not the case. Aerosols are mainly a product of the Northern Hemisphere, where most of the global warming of the last 150 years has occurred; a direct contradiction to this hypothesis! Also, while the air over the United States and Europe has been getting gradually cleaner, it has been getting gradually worse over most of the Far East. The real world observations do not fit the aerosol hypothesis!

In summation:

On one hand we have Bill Gray using pattern recognition, the mathematically acceptable method of predicting the future state of a chaotic, coupled, complex, non-linear system, to predict future climate change and comment on the nature of the climate system. He has a track record of success with this method and his statements fit the observations precisely, because they are derived completely from the observations.

On the other hand, we have the climate change modelers using mathematical models, a method that can not possibly generate a working model of climate change according to chaos theory, to predict a high probability of catastrophic warming of the Earth’s atmosphere. To date, the Earth is not cooperating. The warming effect of CO2 seems to be confined to the warming effect of CO2 and the positive feedbacks are either AWOL or being cancelled out by ‘mysterious forces’! The track record of success for the models is a kin to blind squirrels finding nuts.

There are no peer-reviewed papers documenting a negative water vapor feedback, because the process of increased evaporation in warmer temperatures is not in dispute. Harpooning this little straw man proves nothing. What is in dispute is the integration of this process into the climate system and the resulting net effect. Ridiculing Dr. Gray for not having mathematical formulas explaining how the net effect is zero does not make him any more wrong, nor does it make the computer models any more right. Only the observations of global climate can do that, and right now, those observations favor Dr. Gray and the other AGW crisis skeptics!

Andrew Dessler said...

Jim Clarke-

When Bill Gray and I talk about the WV feedback, we're talking about exactly the same thing: does H2O in the upper troposphere increase or decrease if one adds CO2 to the atmosphere. It's that simple.

I have published data that shows that the WV feedback is positive (see the Minschwaner and Dessler paper on my webpage). This paper is not simply integrating differential equations, but is based on actual measurements of H2O in the atmosphere.

Bill Gray has no data to show that it does not and he has not theory as to why it would not. He's got nothing. That's why no credible scientist believes him.

Regards.

EliRabett said...

To make a claim in a scientific forum for which you have no evidence is serious research misconduct. Gray has stepped over the line, or if not is walking along it.

Anonymous said...

Dr. Dessler,

Thank you for reading and commenting on my post. I took your advice, reviewed your paper with Minschwaner and found it very thorough and well-done. At the same time, I believe the paper and your comment demonstrate exactly what I was talking about.

You went through a great deal of effort to build a model of the tropical atmosphere. Your model, which is built upon the backs of previous studies, has about a half dozen assumptions on top of the unspecified assumptions that went into the previous works you sited. Your model, however, does show a marked improvement over previous models in generating upper tropical tropospheric water vapor correctly. Your observational analysis, also containing some assumptions and restrictions, does reveal a positive water vapor feedback in the upper tropical troposphere, although it is less than assumed by the IPCC. Your model is closer to the apparent reality, but it is not there yet.

So what does this tell us about global atmospheric water vapor under increasing atmospheric CO2? Perhaps nothing!

It is not difficult to visualize a mechanism for your findings. Warmer water temperatures, all else being equal, will likely generate more and larger convective towers in the tropics, transporting more water vapor to the upper troposphere over time. However, the increased evaporation, resulting cloud cover and rain would tend to cool the water temperatures, while the middle and lower troposphere end up with slightly less water vapor due to the more efficient condensation in the convective process. The total column water vapor may end up being less than when the water was cooler, resulting in a (temporary) negative feedback! It would only take a very slight reduction in water vapor in the lower levels to cancel out any increase in the UT.

Also, increased flow into the UT will likely result in an increase in subsidence over the subtropics, possibly reducing the total water vapor in that region.

Also, the effect you describe has undoubtedly been going on forever and is not driven by changing CO2, but by changing water temperatures. You may argue that water temperatures will be warmer with increasing CO2, but the atmosphere will also be different. If the effect of increasing CO2 is to warm the upper troposphere more than the surface, this will effect lapse rates and convection. The net result may be less UT water vapor than what occurred in the 1990s.

Will the same mechanism you modeled and measured in the tropics apply to the rest of the globe, where convection is not the dominant weather maker?

If CO2 warms the planet more in the high latitudes than in the tropics, the temperature differential across the hemispheres will be reduced, possibly resulting in a slight reduction in the number and intensity of synoptic lows. How will this effect total atmospheric water vapor?

Then there are the other climate forcers. The effects of increasing CO2 on water vapor with increasing solar forcing may be different than the effects of CO2 on water vapor with decreasing solar forcing.

These questions are just a tiny fraction of all questions that could be asked, and there will always be more possibilities than we even know to ask about! An answer to one question may only be the right answer at that particular time under those particular conditions. The countless assumptions that go into GCMs are not all correct, and the ones that are correct today, may not be correct tomorrow!

You have done a very good job at narrowing down the possible shape of one small piece of a very large puzzle. This would be a step in the right direction if the puzzle was stagnant, but it isn't. It is in constant flux and when things change in one part of the puzzle, the shape of all the pieces shift a bit.

So in my view, you may be doing brilliant work, but it is an endeavor that nature will ultimately show to be hopeless for the prediction of future climate.

As to Bill Gray...

I was not there when you two spoke, so I can not comment on what each of you said or understood. On the couple of occasions when I have heard Prof. Gray speak about the water vapor feedback loop, I came away with the impression that he was speaking about the entire cycle of water vapor throughout the atmosphere, and not just UT water vapor in the tropics.

You wrote:

"Bill Gray has no data to show that it does not and he has no theory as to why it would not. He's got nothing. That's why no credible scientist believes him."

This is not true! In fact, he has the data that trumps all other data! There is no room in the recorded global warming for significant positive feedbacks from increasing CO2! If there are significant positive feedbacks, then it should definitely be warmer than it is!

So despite his near total lack of differential equations, Bill Gray’s theory about increasing CO2 is currently more accurate than the IPCCs! Yes, the consensus view and all those papers are so much more impressive, but it is still the AGW crisis skeptics that appear to be winning the argument at the thermometer!

My definition of a credible scientist is one who creates theory from observation (past and present), and then uses that theory to predict future observations successfully. Your definition seems to require a scientist to be able to describe all physical interactions in mathematical equations, (that don’t have to mesh entirely with past or present observations) and use only those to predict future observations.

That is not a requirement of the scientific method.

Sincerely,

Andrew Dessler said...

Jim Clarke-

Thanks for your comments. Here are a few responses:

You wrote:
You went through a great deal of effort to build a model of the tropical atmosphere. Your model, which is built upon the backs of previous studies, has about a half dozen assumptions on top of the unspecified assumptions that went into the previous works you sited. ... Your observational analysis, also containing some assumptions and restrictions, does reveal a positive water vapor feedback in the upper tropical troposphere, although it is less than assumed by the IPCC. Your model is closer to the apparent reality, but it is not there yet.

I respond:
I agree that our analysis includes assumptions. But so do all scientific analyses. The assumptions in our model, such as the fact that radiative cooling balances adiabatic compression, or that the atmosphere maintains close to an adiabatic lapse rate, are all well agreed upon, just like we all agree that force equals mass times acceleration. My point is that the existence of assumptions in an analysis should not cast doubt on it --- doubt should arise if you think any one of our assumptions is wrong.

You wrote:
It is not difficult to visualize a mechanism for your findings. Warmer water temperatures, all else being equal, will likely generate more and larger convective towers in the tropics, transporting more water vapor to the upper troposphere over time. However, the increased evaporation, resulting cloud cover and rain would tend to cool the water temperatures, while the middle and lower troposphere end up with slightly less water vapor due to the more efficient condensation in the convective process. The total column water vapor may end up being less than when the water was cooler, resulting in a (temporary) negative feedback! It would only take a very slight reduction in water vapor in the lower levels to cancel out any increase in the UT.

I respond:
I think you misunderstand what we’re trying to do in this paper. The question we’re answering is what happens to upper trop water vapor if the surface warms. We’re not making a prediction about what happens to surface temperature if you add CO2 to the atmosphere. In other words, we’re studying the water vapor feedback in this paper. I would also add that the “water vapor feedback” is mostly due to UT water vapor. Lower altitude water vapor has a much smaller greenhouse effect because of the reduced contrast with the surface temperature.

What we show is that as the surface warms, UT water increases. Thus, we get a strongly positive feedback.

You wrote:
Also, increased flow into the UT will likely result in an increase in subsidence over the subtropics, possibly reducing the total water vapor in that region.

I respond:
Bill Gray makes this argument also. The problem with it is that it’s energetically forbidden. It is impossible to put together any model that gets this result because energetics prohibits increased subsidence and decreased water vapor ... you just can’t get the energy balance to work out.

You wrote:
Also, the effect you describe has undoubtedly been going on forever and is not driven by changing CO2, but by changing water temperatures. You may argue that water temperatures will be warmer with increasing CO2, but the atmosphere will also be different. If the effect of increasing CO2 is to warm the upper troposphere more than the surface, this will effect lapse rates and convection. The net result may be less UT water vapor than what occurred in the 1990s.

I respond:
You’re right. Our analysis says nothing about what caused the surface temperature increase. We’re only looking at the change in UT water as the surface T changes.

You wrote:
Will the same mechanism you modeled and measured in the tropics apply to the rest of the globe, where convection is not the dominant weather maker?

I respond:
No, the assumptions that go into this, like an adiabatic lapse rate, only apply to the tropics. I should note, however, that the people arguing for a negative feedback (Lindzen, Gray) are also talking exclusively about the tropics.

You wrote:
These questions are just a tiny fraction of all questions that could be asked, and there will always be more possibilities than we even know to ask about! An answer to one question may only be the right answer at that particular time under those particular conditions. The countless assumptions that go into GCMs are not all correct, and the ones that are correct today, may not be correct tomorrow!

I respond:
There is certainly uncertainty in our knowledge of the water vapor feedback. But I take a more optimistic view. We have a theory that 1) fits the observations, 2) contains the physics we believe is going on, 3) contains no unreasonable assumptions, and 4) there is no competing theory. Based on this, the scientific community has pretty much concluded that it’s “case closed” on this problem: the water vapor feedback is strongly positive.

You wrote:
I was not there when you two spoke, so I can not comment on what each of you said or understood. On the couple of occasions when I have heard Prof. Gray speak about the water vapor feedback loop, I came away with the impression that he was speaking about the entire cycle of water vapor throughout the atmosphere, and not just UT water vapor in the tropics.

I respond:
That’s not the impression I get from him. I believe he is directly contradicting the results of the Minschwaner and Dessler paper.

You wrote:
"Bill Gray has no data to show that it does not and he has no theory as to why it would not. He's got nothing. That's why no credible scientist believes him."

This is not true! In fact, he has the data that trumps all other data! There is no room in the recorded global warming for significant positive feedbacks from increasing CO2! If there are significant positive feedbacks, then it should definitely be warmer than it is!

I respond:
Where does this come from? Why do you think that present-day warming should be much greater than observed. This is the first time I’ve heard that argument. Also, Bill Gray does not make this argument. He has no data set that’s comparable to the UARS data we show, nor does he have a model that’s comparable to the model we showed. He’s got nothing but anger.

You wrote:
My definition of a credible scientist is one who creates theory from observation (past and present), and then uses that theory to predict future observations successfully. Your definition seems to require a scientist to be able to describe all physical interactions in mathematical equations, (that don’t have to mesh entirely with past or present observations) and use only those to predict future observations.

I respond:
My definition of a scientist is one who publishes falsifiable analyses. Because Bill Gray shows no data, has no model, and publishes no papers, his work cannot be falsified. All he does is assert the feedback is negative, but he shows no work to support it. That’s not science.

Anonymous said...

Gee really why would Al Gore consult with NASA's chief climate scientist when he makes a Keynote presentation on climate change? Indeed.
Gore should have consulted with the editors of Newsmax just to know the exact CO2 ppm data.

Your bias stinks.

What makes Gore more credible on AGW than Bill Gray?
For example that Gore does not consult with Bill Gray, who is quite frankly, became a running joke as far as climatology is concerned.