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11 scientists' opinions on the global warming consensus

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“The final IPCC report carries an authority and depth far beyond that of any individual scientist or small group of scientists, no matter how gifted or experienced.”


-- Bruce A. Wielicki, of NASA’s Langley Research Center, Principal Investigator for CERES, a project that uses Earth-orbiting satellites to monitor how clouds affect our climate.



“There cannot be a 100% proof as you have in mathematics.”


-- Colin Price, Professor of Geophysics and Planetary Science at Tel Aviv University



“The best way out of the dilemma of which expert to believe is to undertake the task of understanding the science itself.”


-- Kerry Emanuel, Professor of Meteorology at Massachusetts Institute of Technology.



“Naysayers are playing devil’s advocate or not qualified to discuss the science.”


-- J. H. LaCasce, Department of Meteorology at the University of Oslo, Norway



“...what is significant in the case of the universal scientific consensus regarding global warming is the agreement of normally distant fields of scientific endeavour.”


-- Stuart S. Sumida, Professor of Biology at California State University in San Bernardino



“There will always be a marginal fringe in most aspects of science.”


-- John Kermond, UCAR visiting scientist with NOAA’s Climate Program Office.



“One has only to examine the basic physics of adding CO2 to the atmosphere”


-- David Pimentel, Professor in the Entomology Department at Cornell University



“Scientific consensus is not an agreement on opinions — is Picasso better than Rembrandt, or pepperoni better than anchovies?”


-- Richard B. Alley, Evan Pugh Professor in the Department of Geosciences, and Earth and Environmental Systems Institute at Pennsylvania State University



“It’s a lot like the debate on smoking, where for years some scientists said we can’t be sure smoking is hazardous to health. While society waited for higher levels of proof many people died.”


-- P. Dee Boersma, holder of the Wadsworth Endowed Chair in Conservation Science in the Department of Biology at the University of Washington in Seattle.



“Consensus at its heart is a political notion based on powers of persuasion, nuance and belief.”


-- John R. Christy, Alabama State Climatologist and Director of the Earth System Science Center and Professor of Atmospheric Science at the University of Alabama in Huntsville



“the very idea of consensus in such an immature and multi- faceted subject as climate change should be suspicious ab initio.”


-- Richard S. Lindzen, Alfred P. Sloan Professor of Atmospheric Sciences at MIT.



Clearly the idea of a scientific consensus itself is a polarizing issue. Are Lindzen and Christy "on the fringe" or are they correct that the idea of a consensus itself is errant?

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Depends if one is part of the cult or not of global warming. No need for rational debate if one 'believes'....is filled with the warm glow of absolutism.



would you say the same about evolution, or gravity for instance?


I mean we don’t exactly know what causes either of them fully, or at some 100% level, so what does it mean really? On that though, both have a rather large basis of support in terms of science, which leads me to believe they are real, or true, simply because I don’t know what else you would say really.

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In "QED, The Strange Theory of Light and Matter" available from the Princeton University Press, Richard Feynman has this to say about whether or not the listener will understanding his lecture on physics.


"The next reason you might think you don’t understand what I am telling you is, while I am describing to you how Nature works, you won't understand why Nature works that way. But you see, nobody understands that. I can't explain why Nature behaves in this peculiar way.


Finally, there is this possibility: after I tell you something, you just can't believe it. You can't accept it. You don't like it. A little screen comes down and you don't listen anymore. I'm going to describe to you how Nature is - and if you don't like it, that's going to get in the way of your understanding it. It's a problem that physicists have learned to deal with: They've learned to realize that whether they like a theory or they don't like a theory is not the essential question. Rather it is whether or not the theory gives predictions that agree with experiment. It is not a question of whether a theory is philosophically delightful, or easy to understand, or perfectly reasonable from the point of view of common sense. The theory of quantum electrodynamics (QED) describes Nature as absurd from the point of view of common sense. And it agrees fully with experiment. So I hope you can accept Nature as She is - absurd.


I'm going to have fun telling you about this absurdity, because I find it delightful. Please don't turn yourself off because you can't believe Nature is so strange. Just hear me all out, and I hope you'll be as delighted as I am when we're through."


I see two essential elements in the above. Science isn't about "why", it's about "how." If you want to know about "why" study philosophy or religion. Next, when a theory gives predictions that agree with experiment, it must be believed. It you can't do that you should avoid science.


So Newton had some theories about gravity. He made some experiments and the results agreed with his theory. We have to believe. The results were so good in fact they were upgraded from theories to laws of nature. Then Einstein came along and essentially said "well except in these extreme and special circumstances." Experiments showed that Einstein was right so Newton's laws of gravity went back to being theories. I don't know if humans will be so bold as to declare any theories "laws of nature" again. Einstein put science out of the "laws" business.


So science is a show me game. It's all about the measurements. Scientific consensus is nearly meaningless. So why do we talk about it then? Two reasons: probability and time.


Some things are really hard to measure or they are governed by complex systems. So the best you can say is that the probability of a particular outcome is X percent, or one could say the theory correlates with data X percent of the time. If X is 90%, the theory might be considered good depending on the branch of science. If X is 40% most scientists would say try again regardless of the branch. In physics a theory generally must describe some thing very well for to be considered a good theory. For example Bohr's theory of the hydrogen atom works great for hydrogen, but not for other more complex atoms. It still won him the Nobel Prize.


Next, some experiments take too long for our patience. Evolution and Global Warming fall into that category. That is why we must extract data from the past. The guardians of evolution theory, in the past, use to reject any data that did not support the concept of Gradualism. Gradualism said that all things happen very slowly like the formation of the Grand Canyon. Nothing happens like the dinosaurs all being killed off by a meteor striking the Earth. Eventually there was enough data showing that species died off quickly and evolved quickly that they came up with the idea of punctuated equilibrium. So the theory of evolution was modified based on measurements. That’s science.


So like evolution, global warming theory has two problems. First, the theories only fit the historical measured data some percent of the time. Also, much of this data is extrapolated from ice cores, tree rings and the like. We only have significant actual data for about the last 150 years. I'm not and expert so I don't know how good the extrapolations are, but it does matter. For example, I have yet to see a climate computer model that can be set to conditions of say 10,000 years ago that then tracks the actual known climate conditions that followed for the next 1000 or more years. Show me that and I might get excited about global warming predictions.

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So Newton had some theories about gravity. He made some experiments and the results agreed with his theory. We have to believe. The results were so good in fact they were upgraded from theories to laws of nature. Then Einstein came along and essentially said "well except in these extreme and special circumstances." Experiments showed that Einstein was right so Newton's laws of gravity went back to being theories. I don't know if humans will be so bold as to declare any theories "laws of nature" again. Einstein put science out of the "laws" business.

Well I don't know about any of your post' date=' I'm just responding to this because it seems to be a point that most people don't understand.


[u']Theories do not turn into laws. Ever. Don't even ask.[/u]


A law of nature is something that is observed to happen. We observe that the sun rises every day, and we can provide some mathematics that tell us a time and everything else. This is a law. It was never a theory, all it has ever been is an observation.


Theories tend to explain laws. They tell us the why (maybe not the same type of "why" you're referring to -- as a purpose, but you know what I mean). A theory about the sun rising is that the sun orbits our planet. This is nice and all, and it agrees with observations, but it makes a prediction -- that the sun would be the same size year round. This has of course been found to be incorrect and you can actually do this experiment yourself -- take a picture of the sun from the same place at noon (don't look at it!) every month for a year, and you'll notice that it grows and shrinks.


Now either two things are happening: the sun is actually growing and shrinking, or the theory is incorrect for some reason. If the sun is growing larger/smaller, we would be able to feel that the sun is emitting more/less radiation, and this is not the case.


So another theory is that we orbit the sun (in an ellipse, but of course it's not precisely an ellipse, the path changes over thousands of years) and of course we all know that every prediction about this theory has been found to be true. The theory that we orbit the sun will never be "elevated" to the status of law because it's so self-intuative or whatever. It will always be a theory, never a law. End of story.


We find the same thing with gravity. Unlike what you're saying, there is a difference between the law of gravity and the theory of gravity. The law of gravity is that things fall, and the theory is that matter attracts itself, and this goes along with a couple math equations. The theory of gravity was never turned into a law. Of course now we have relativity, which is an alternative theory of gravity, and it basically does the same thing the theory of gravity did -- explain the law of gravity. It did not overthrow the law of gravity. The law of gravity has always been the law of gravity and theory of gravity has always been the theory of gravity


Evolution is the same way. You'd probably be surprised to find out that there is a law of evolution. The law of evolution is that the frequency of different alleles in a population's gene pool changes over time (ie, things evolve). This has simply been observed and is a fact: we can see it happening in labs and we see it happening in the fossil records.


The theory of evolution basically says that allele frequencies change over time because organisms undergo genetic change and experience differential reproductive success due natural selection. The theory of evolution is very successful, for instance we use it every year to figure out which flu virus will be most predominant so we can efficiently send out flu vaccinations to different regions of the world.


I always found it funny because it's not the theory of evolution that people have problems with (and at the same time people always use the argument, "evolution is only a theory"). The problem that people have with evolution is the law, or the observed fact that species evolve over time.


Btw the theory of punctual equilibrium has not replaced gradualism. It is still believed that gradualism can and does occur. Biologists have moved past the either or debate -- either punctuated equilibrium or gradualism, to the position that it's probably both.


Punctuated equilibrium, however, is the dominant species-changing force throughout most of evolutionary history. The alligator/crocodile is an example of gradualism, not punctuated equilibrium, guiding evolution. This recent discovery is an example of punctuated equilibrium at work.

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First, let me apologize for diverting the topic of this thread. The thread is about the usefulness of scientific consensus. Please however let me clarify my thoughts on laws of nature.


Much of scientific research, particularly in the past, has been an attempt to discover exceptionless regularities in nature. Those thought to have discovered such exceptionless regularities had there names attached to them. For example: Newton's laws, Maxwell's laws (or equations), Gauss's laws, Faraday's law, and so on. Modern science has found exceptions to most of these laws. Few people today believe we will ever fully discover exceptionless regularities in nature. Modern thought is that laws of nature are statements that describe causal powers. Exceptions to such laws based on this definition are considered acceptable. It would have been better for me to say science is not longer in the exceptionless regularities business and is now in the causal powers business.


Back to the topic of scientific consensus. In my last post I stated that scientific consensus is of almost no value. Its primary value is to encourage continued work on promising research. Maybe an example would be illuminating. Say some scientist proposes a hypothesis, collects data from an experiment, or compiles data from the historical record, and this data shows some significant correlation to the hypothesis. Based on the significant correlation found, the scientist attempts to publish a paper. Okay, where he attempts to publish makes a difference. All good scientific journals are peer reviewed. That means experts in the field will review the work and reach some level of consensus about its worthiness for publication. If it passes that threshold and is published then a lot of scientists will see it. If a scientist reads the paper and has reasons to disagree with it, he can write the author or the journal editor and tell them why the paper is wrong or perhaps not quite on the right track. If no one does this, in some respects, a higher level of consensus is reached. So when does a scientist know he's really on to something. Generally when others start calling his hypothesis a theory and extending the research by their own work.


It does seem that there is a threshold for when a hypothesis becomes a theory and for when a theory becomes a "Theory." These thresholds are generally passed when significant amount of data has been collected that supports the hypothesis in the original or modified form. In other words that data can't be ignored. So who decides that enough is enough? A consensus of scientific community decides. How do they do this? Generally by running out of good arguments against the hypothesis. How is this best achieved? By encouraging decent. Decent is a form of encouragement.

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I think it has more to do with skepticism's role in science. All scientists are naturally skeptics, it works kind of like natural selection: only the good ideas make through the scrutiny of peer-review.

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Descent as a form of encouragement. Where do I start? Think of it as constructive criticism. Accepting criticism is always difficult. Humility isn't a strong suite of our species. Many studies have proven that researchers find what they are looking for, regardless of the true outcome of an experiment. That is why medical science does double blind studies. Many studies have also shown that all individuals filter out information that support their beliefs and reject those that don't. If you don't believe that, the next time you finish reading a news paper go back through the paper and find the articles you chose not to read or finish. Most will find that they rejected those that did not support their own beliefs. Many of the threads on global warming show this tendency. Many won't read research supported by "Big Oil." Others reject research supported by proponents of "Big Government." A good scientist should read both and reject only those with bad data. In science, it is all in the data.


A person publishes for two reasons; to inform and to confirm. The inform part is the scientist saying "Hey everyone, look at this neat thing I found." The confirm part is the scientist saying "Okay, but did I miss anything?" Answering that second question in a negative way is a good thing for the publishing scientist and all science.


By the way, most scientists prefer to publish in good peer reviewed journals. One reason for doing this is to limit the embarrassment caused by promoting bad science. The small group of reviewers, by rejecting the paper, save the scientist's reputation. Think of those cold fusion researchers from Utah a few years back. Initially they got lots of positive publicity. Then no one could reproduce there research. I bet they wished their paper was rejected.


Finally, sometimes descent has to be a bit brutal. Most hold their opinions quite dear. It's difficult sometimes to move people away from incorrect beliefs. As long as the descent does not fall into ad hominem attacks, you are on safe ground. So yes, I may be capitalist, or a socialist, or my nose may be big, but the important thing is my data.

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Hey Bascule


"Are Lindzen and Christy "on the fringe" or are they correct that the idea of a consensus itself is errant?"


Here's a few more quotes for the fringe

Personally I remain unconvinced of a consensus, errant or not !


Professor Paul Reiter IPCC & Pasteur Institute Paris

“The global warming alarm is dressed up as science, but it’s not science, it’s propaganda”


Professor Nir Shaviv Institute of Physics University of Jerusalem

“There is no direct evidence which links 20th century global warming to anthropogenic greenhouse gases”


Professor Ian Clark Dept of Earth Sciences University of Ottawa

“You can’t say that CO2 will drive climate, it certainly never did in the past”


Professor Tim Ball Dept of Climatology University of Winnipeg

“If the CO2 increases in the atmosphere, as a greenhouse gas, then the temperature will go up, but the ice core record shows exactly the opposite, so the fundamental assumption of the whole theory of climate change due to humans is shown to be wrong”


Professor John Christy Dept of Atmospheric Science University of Alabama & Lead Author IPCC

“I’ve often heard it said that there is a consensus of thousands of scientists on the global warming issue and that humans are causing a catastrophic change to the climate system. Well I am one scientist, and there are many, that simply think that is not true”


Professor Philip Stott Dept of Biogeography University of London

“The IPCC like any UN body is political, the final conclusions are politically driven”


Professor Richard Lindzen IPCC & M.I.T.

“People have decided you have to convince other people that, since no scientist disagrees, you shouldn’t disagree either. But whenever you hear that in science that’s pure propaganda”


Professor Patrick Michaels Dept of Environmental Sciences University of Virginia

“Anyone who goes around and says that carbon dioxide is responsible for most of the warming in the twentieth century hasn’t looked at the basic numbers”

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