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A Positive Human Influence on Global Climate? Robert Mendelsohn, Meet Gerald North!

By Robert Bradley Jr. -- May 6, 2010

“[Robert] Mendelsohn’s position is rather similar to yours…. He believes the impacts are not negative at all for the US and most of the developed countries. Most impact studies seem to be showing this. It leads us to think that a little warming is not so bad. Glad I have kept my mouth shut on this issue of which I know so little.”

– Gerald North (Texas A&M) to Rob Bradley (Enron), November 12, 1999

“I agree that the case for 2C warming [for a doubling of manmade greenhouse gas forcing in equilibrium] is pretty strong.”

– Gerald R. North to Rob Bradley, email communication, August 13, 2007.

Yesterday, the Wall Street Journal published my letter-to-the-editor rebutting Kerry Emanuel’s letter, which, in turn, was critical of his fellow MIT climatologist Richard Lindzen’s op-ed, “Climate Science in Denial.”

My arguments opposing those of Professor Emanuel (see entire letter below) are fairly straightforward, but I end with this challenge:

“But when will many climate scientists, including Mr. Emanuel, face Climategate and the fact that the human influence on climate, on net, is as likely to be positive than negative?”

Is this challenge rash, or is it backed by the facts?  Well, let’s consider the views of an esteemed climate economist and an esteemed climate scientist. They are, respectively,

Robert O. Mendelsohn (Edwin Weyerhaeuser Davis Professor of Forest Policy; Professor of Economics; and Professor, School of Management)

Gerald R. North (Distinguished Professor, Physical Section, Department of Atmospheric Sciences and the
Department of Oceanography

Dr. North’s long held sensitivity estimate of 2ºC for a doubling of atmospheric greenhouse concentrations is one-third below the “best guess” of the Intergovernmental Panel on Climate Change (or the IPCC’s best guess is one-half greater than that of Dr. North). That is a big difference, and if you believe Mendelsohn et al. that a 2ºC for 2x results in net positive benefits for the world, then voila!

Is it radical to believe that the human influence on climate, on net, has more positives than negatives for many decades out and even beyond a century or more?  After all, the CO2 fertilization effect is a strong positive, and warmer and wetter is going in the right direction for the biopshere…

Perhaps CO2 as the green greenhouse gas is ‘closet’ mainstream, if North’s (private) views are considered.

Therein lies one of the peculiarities of the multi-disciplinary climate-change debate, for Gerald North may privately believe something that he is unwilling to admit in public.

Appendix: Robert Bradley Jr. “Doubts on Climate Are Reasonable” (Wall Street Journal letter-to-the-Editor)

Kerry Emanuel’s letter of April 28 illustrates some of the major points of Richard Lindzen’s op-ed, “Climate Science in Denial” (April 22). It is bad enough that Mr. Emanuel refers to major misrepresentations, errors and unethical behavior among scientists involved in the Intergovernmental Panel on Climate Change reports as “minor errors.” But claiming that Mr. Lindzen’s opinions are at odds with basic climate theory, which does not support climate alarmism, is worse.

Mr. Emanuel suggests that such disputed matters as sea-level rise and glacier dynamics (which depend on factors other than global warming) form a “vast body of evidence” for climate change. But no one disputes that climate is changing and has always been changing. So what is his point?

Mr. Emanuel implicitly attacks a recent paper by Mr. Lindzen and Yong-Sang Choi (2009) that, indeed, did have important errors as acknowledged by Mr. Lindzen. But according to the authors, corrections have not altered its conclusion of a low climate sensitivity to man-made greenhouse gases.

The majority of the public is right to discount anthropogenic climate change as an environmental concern. But when will many climate scientists, including Mr. Emanuel, face Climategate and the fact that the human influence on climate, on net, is as likely to be positive than negative?

Robert Bradley Jr.

CEO & Founder, Institute for Energy Research, Houston


  1. jthomas  

    Dr. Emanuel is correct. Richard Lindzen, Dr. Emanuel’s colleague at MIT, is in the minority, a minority that refuses to let go of the politicization of climate science, and is increasingly marginalizing itself into a state of denial and conspiracy theories.

    Fortunately, science is not fought in Letters to the Editor; Dr. Emanuel’s and Dr. Lindzen’s science, research, and papers are available to the entire scientific community – as well as to the public. Science advances on the evidence; consensus develops and changes over time as new and more refined data is captured and technology advances and serves to refine or change our understanding of climate over time.

    Should scientists sit back, as Dr. Emanuel did for decades, and say nothing about bad science, misrepresentations, and the politicization of science? Should Dr. Emanuel shut-up and lock himself in his office leaving science to be trashed by the likes of ignorant and politically motivated politicians like U.S. Sen. Jim Inhofe (R-Okla), a man who is to climate science what Creationists are to evolutionary biology? Or should they speak out against the trashing of, and politicization of science? For one, I am glad that well-respected scientists like Dr. Emanuel, have chosen not remains silent.

    Dr. Emanuel wrote a concise understanding of anthropogenic climate change in a clear way designed for the laymen that people ought to read:

    “Phaeton’s Reins: The human hand in climate change.”


    Does that represent the scientific consensus or not? I’m willing to bet it does, contrary to the claims of those on the political right who adopted Al Gore’s mantra: “Climate Science: all politics, all the time.”

    Contrary to Lindzen’s claims, the so-called “Climategate” is nothing that he claims it is, but, in order to perpetuate the myth that no scientific consensus exists on anthropogenic climate change, it serves it’s political purpose quite well – and quite transparently: it is another act of conspiracy mongering for a political purpose to the detriment of real science, and scientific research, and the ability of this country to respond appropriately to large-scale challenges.


  2. Robert Bradley Jr.  

    Well, I could not disagree more.

    Gerald North is just as mainstream as Professor Emanuel and is quite nonalarmist. And you haven’t come to grips with what North and Mendelsohn are really saying–lower range sensitivities indicate that the human influence could be positive, not negative. That CO2 is the green greenhouse gas.

    And consider the very recent view of another respected scientist, Roger Pielke Sr.

    Beware of groupthink and the argument from authority.


  3. jthomas  

    Emanuel is an “alarmist?” It’s not even a scientific term – it’s a political term, like the mythical “Climategate.” But that does illustrate my point.

    You missed the point – and the logic. The evidence and consensus of climate science is against Lindzen and his claims. And calling them “alarmists” only serves to discredit your position.


  4. Richard W. Fulmer  

    There are basically three groups involved in the climate debate:
    1. Those who believe that human actions are enhancing the greenhouse effect with catastrophic results
    2. Those who believe that human actions are enhancing the greenhouse effect with beneficial impact at best or a moderate impact at worst
    3. Those who do not believe that human actions are enhancing the greenhouse effect

    Assigning labels to these groups facilitates conversation. Choose any labels you like. No such label, however, will be “scientific.”


  5. jthomas  

    That’s why “labels” are intellectually dishonest. They say nothing about the scientific validity of the positions and are used to promote “beliefs” as if they were legitimate and equally valid scientific theories. They are not.

    That is yet another reason climate scientists are fighting back against the politicization of science:


    Lead Letter Published in Science magazine, May 7, 2010
    From 255 members of the National Academy of Sciences:


    That is why organizations like Robert Bradley’s Institute for Energy research will eventually find it is not in their long-interest to be on the wrong side of science.


  6. Richard W. Fulmer  

    I notice that the “climate statement” that you linked to in your last post uses the label “deniers” for those people who do not share the catastrophic view of climate change (effectively lumping groups 2 and 3, as defined in my previous post, together). By your own argument, use of labels is “intellectually dishonest” and “unscientific,” and therefore completely invalidates their position.


  7. Richard W. Fulmer  

    As Professor Emanuel states on page 7 of his “Phaeton’s Reins” piece (which you cited above), the effect of CO2 emissions on water vapor will determine whether global warming is catastrophic or benign. If rising emissions trigger a positive feedback effect, we’re in trouble. The computer models all assume that it does.

    However, CO2 concentrations have been much higher in the past, raising the question of why Earth’s climate did not spiral out of control then. A number of studies (including several by Richard Lindzen) suggest that there are actually negative feedbacks loops in effect regulating the climate. Emanuel dismisses these studies on page 18, yet on pages 7-9, he admits the uncertainty surrounding water vapor. (I note, in passing, that page 18 contains the “unscientific” label “les refusards” in referring to people who disagree with him, presumably invalidating all of Emanuel’s arguments in your eyes.) Since the feedback effect is the key issue, more work needs to be done in this area.

    The “climate statement” you referenced your last post, implicitly refers to the precautionary principle, stating: “taking no action poses a dangerous risk for our planet.” This principle cuts both ways, however. If the situation is as dire as you believe, then we cannot afford to make any mistakes. And some of the proposed solutions to the problem could well make things worse. For example, if we adopt policies that drastically increase the cost of energy in the United States, we could drive energy-intensive production offshore to countries that are far less energy efficient.


  8. Richard W. Fulmer  

    Interesting – an open letter from government-paid scientists to politicians complaining about the politicization of science.


  9. jthomas  

    “By your own argument, use of labels is “intellectually dishonest” and “unscientific,” and therefore completely invalidates their position.”

    Then the use of “global warming alarmists” and “AGW believers” is justified? And what was Al Gore 25 years ago when Emanuel told him to his face in Gore’s Senate hearings, that, “no, all scientists do NOT agree that there is global warming,” much less anthropogenic global warming?

    The irony that Inhofe and the political Right are still fighting the same political battle against Al Gore with the same argument of 25 years ago as the science passed them by doesn’t escape us climate scientists. As I said earlier, the political Right has inherited Gore’s tactics with vigor: “Climate science: all politics, all the time.”

    “However, CO2 concentrations have been much higher in the past, raising the question of why Earth’s climate did not spiral out of control then.”

    “Raising the question” is legitimate. Using the past to predict the future while ignoring additional contributing factors is not science.

    “Interesting – an open letter from government-paid scientists to politicians complaining about the politicization of science.”

    Interesting – posts from Richard W. Fulmer, principal of a __________-funded organization. (Fill in the blank.)

    Institute for Energy Research has received $307,000 from ExxonMobil since 1998.

    $37,000 ExxonMobil Foundation
    Source: Institute for Energy Research website 5/04

    $45,000 ExxonMobil Corporate Giving
    Climate Change and Energy Policy Issues
    Source: ExxonMobil 2004 Worldwide Giving Report

    $65,000 ExxonMobil Corporate Giving
    Source: ExxonMobil 2005 Worldwide Giving Report

    $65,000 ExxonMobil Corporate Giving
    Source: ExxonMobil 2006 Worldwide Giving Report

    $95,000 ExxonMobil Foundation
    Source: ExxonMobil 2007 Worldwide Giving Report


    Did you mention how you want to influence government policy?

    “For example, if we adopt policies that drastically increase the cost of energy in the United States, we could drive energy-intensive production offshore to countries that are far less energy efficient.”

    Did you mention your failure to push nuclear power in the last 25 years, a sure-fire way to neutralize political arguments by promoting the most-efficient, NON CO2 energy source successfully used world-wide?

    Did I miss your energetic support for nuclear power somewhere? Or Exxon-Mobil’s?

    Or is “les refusards” an appropriate term after all?


  10. Robert Bradley Jr.  


    You have it backwards. My beliefs predate funding. My views on climate science and economics were formed in the 1990s while working at Enron, a climate alarmist company.

    Enron, not Exxon, is the more important in this regard. Please visit my website, http://www.politicalcapitalism.org and and click on Enron.

    BTW, those receiving funding from government or a Left foundation–does that automatically disqualify them too? Or a Shell or BP that have supported climate alarmism for branding purposes?


  11. cknappenberger  


    We still have a lot to learn about the earth’s climate system. The recent (past decade or two) interest in “climate change” has elevated the field of climate science to the to one of national and international interest. But just because we now read about climate every day doesn’t mean that we have a complete handle on the where, whens, whys, and how much.

    Dr. Lindzen’s investigations into the processes behind climate sensitivity have been going on long before “climate change” was a hot button issue. Long ago he identified processes involving water vapor as an area where important and interesting questions needed to be raised—the answers to which have a great impact on how the earth’s climate will respond to increases in greenhouse gas concentrations.

    While you may consider him to be in the “minority” in continuing to ask these questions (and provide some answers), he is not alone. Roy Spencer has an interesting new book out on the topic, and Roger Pielke Sr. recently pointed to other on-going investigations into clouds and the climate model representations of them.

    Couple these (and other) works which suggest that the climate sensitivity (at least on the shorter time scale—years to multiple decades) is lower than climate model determinations, with the failure of the global temperatures to rise at the projected rate for the past decade (or more) and you have and very interesting and justifiable line of questioning.

    Pursuing interesting leads in what science is all about (of course, it should be done without fear of legal prosecution).



  12. Richard W. Fulmer  

    I’m not a principal of anything. I have a day job (engineer-turned-computer jockey), and volunteer my time to MasterResource – a little editing, a little writing, sweep up after hours.


  13. jthomas  

    “We still have a lot to learn about the earth’s climate system. The recent (past decade or two) interest in “climate change” has elevated the field of climate science to the to one of national and international interest. But just because we now read about climate every day doesn’t mean that we have a complete handle on the where, whens, whys, and how much. ”

    Yes, exactly. Uncertainty exists as every climate scientist broadcasts daily. But uncertainty does not invalidate what the consensus of climate scientists demonstrate.

    To deny that there is a consensus and, instead, insist that there “are basically three groups involved in the climate debate”, as if there is *actually* a debate with three equally valid *beliefs* is nothing more that an political justification.


  14. jthomas  

    “My views on climate science and economics were formed in the 1990s…”

    Well, you are a little ahead of your peers who established their views and positions in the 1980s.

    Fortunately, scientists don’t and can’t think that way.


  15. Richard W. Fulmer  

    Let me understand the ground rules. When you, or anyone who agrees with you, labels the opposition as “deniers” or “les refusards,” that’s legitimate. Any use of labels by the opposition, however, automatically invalidates their arguments, thereby saving you the trouble of actually having to deal with them.

    When government-paid scientists, supporting the government-line, lobby for more government funding, that’s just working within the system. When companies who agree with MasterResource donate to the blog, that’s corruption.

    When you, or anyone who agrees with you, tries to influence government policy, that’s democracy at work. When anyone in the opposition tries to influence policy, that’s “politicization” and must be stopped.

    These rules seem just a bit one-sided to me.


  16. Major Mike  

    Sometimes it seems it’s how many angels can dance on the head of a pin. However, we’re in an interglacial period of an Ice Age, and there have been several periods of greater warming than the current in the past 12,000 years. In that 12,000-year period of warming, sea levels rose over 400 feet, and glaciers retreated. Our modest warming now is notable because it follows the quite cold Little Ice Age. CO2 increased steadily during the Little Ice Age; warming didn’t, although CO2 supposedly has its greatest warming effect at its low end of concentration as it increases.
    A plausible explanation for this is that the atmosphere is always saturated with green-house gases, predominantly water vapor. The negative feedbacks of cloud formation and evaporation as water vapor increases dampen solar-induced warming. The evidence of this is all over the cycles of warming and cooling since the last Ice Age.
    That climate models can’t explain the lack of current warming is truly a travesty, casting enormous doubt on the validity of the models.


  17. Jon Boone  

    Apropos the comments by jthomas, I offer a posthumous riposte by the great physicist, Richard Feynman, adapted from his Caltech commencement address, 1974: http://www.lhup.edu/~DSIMANEK/cargocul.htm. Here’s an excerpt:

    “It’s a kind of scientific integrity, a principle of scientific thought that corresponds to a kind of utter honesty–a kind of leaning over backwards. For example, if you’re doing an experiment, you should report everything that you think might make it invalid–not only what you think is right about it: other causes that could possibly explain your results; and things you thought of that you’ve eliminated by some other experiment, and how they worked–to make sure the other fellow can tell they have been eliminated.

    Details that could throw doubt on your interpretation must be
    given, if you know them. You must do the best you can–if you know
    anything at all wrong, or possibly wrong–to explain it. If you
    make a theory, for example, and advertise it, or put it out, then
    you must also put down all the facts that disagree with it, as well
    as those that agree with it. There is also a more subtle problem.
    When you have put a lot of ideas together to make an elaborate
    theory, you want to make sure, when explaining what it fits, that
    those things it fits are not just the things that gave you the idea
    for the theory; but that the finished theory makes something else
    come out right, in addition.

    In summary, the idea is to try to give all of the information to
    help others to judge the value of your contribution; not just the
    information that leads to judgment in one particular direction or

    I once heard Feynman, in an interview, unbraid a pseudo-scientist by asking, “Do you know how hard it is to really know even the simplest thing?” The elimination of bias, transparency, falsifiability, and accountability are the hallmark of science, with variable control a high priority. Today’s political climate juggernaut is anything but. Feynman must be chortling in his grave at this mockery. Freeman Dyson has made his feelings about the issue quite clear.


  18. Robert R. Reynolds  

    I still think like a geologist that to understand the present you first must have an understanding of past climates and the fact that, man’s slight influence on weather began only a geological moment ago. The Holocene interglacial period climate has been pieced together in considerable detail from proxy data utilizing
    drill cores of sea floors around the world, glacial ice from Greenland and Antartica, tree rings and cave stalagmites. Climate graphs from this data starting with the warming that ended the Wisconsin glacial stage about 12,000 ybp (years before present) and has varied several degrees C up and down ever since. Maximum temperatures, higher than today, were attained around 8,000, 5,000, 2,500 and 1,000 ybp. We have been recovering from the Maunder minimum, a time of low sun spot activity the last 700 years. In their desire to instill fear in citizens of the world, the AGW crew introduced the shameless lie that “never before had world temperatures increased so rapidly nor gone so high” as when man began began using carbon based fuels around 1850. And Dr. Mann devised a master-piece of “cherry picking” by omitting the Middle Ages warm period, yielding the now infamous “hockey stick” graph for which I am surprized the Nobel Prize committee did not award him a prize for chutzpah which ignored the true climate of the Holocene.


  19. Richard W. Fulmer  

    I plead guilty to not pushing nuclear power. If I believed that AGW translated into “apocalypse now,” I probably would be a strong backer. However, I’m in “group 2” (that is, I don’t believe that AGW is catastrophic), so I don’t look a nuclear power under the assumption that CO2 emissions are all that matter. I look at cost as well as emissions and, while nuke is cheaper than either solar or wind, it costs more than (say) natural gas.


  20. Cooler Heads Digest 7 May 2010 | GlobalWarming.org  

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  21. Robert R. Reynolds  

    I still cling to the historical approach. As long as we have ice in our polar regions we remain in a glacial climate and a world temperature a few degrees below what was normal before the present Era. Sea floor drilling has revealed arctic ocean temperatures of 23 deg C in 50 million year old sediment and temps have been declining ever since, culminating with the cyclic Pleistocene glaciations beginning a mere geologic moment, 1.75 million years ago, and the Holocene interglacial period began only 12,000 years ago. The area in southeastern Canada, where the Wisconsin glacial stage was thickest, is still
    rebounding from its load of ice. In the light of abundant geological evidence, I feel that we would be a lot more secure from a return of the ice if we do warm up a few more degrees because another ice age would be far more devestating to mankind and his works. The belief that man can control climate by drastically reducing greenhouse gases is fraught with hazards because our sun is too weak at times to prevent our planet icing up without the “security blanket” effect of Greenhouse gases.


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