JPL on Global Gamble, Harvard’s Holdren on Stages of Climate Denial

By Andrew C. Revkin

Climate scientists keep testing that turbulent world between data and society — an arena far less safe than the laboratory or field camp, where a researcher becomes a potential target for both darts and laurels from those threatened or bolstered by his or her views. One new experiment is a nascent blog at NASA’s Jet Propulsion Laboratory, with a fresh contribution by Josh Willis, whose work on ocean temperature trends has been discussed here. Dr. Willis says those who grasp at short-term wiggles in ocean or atmospheric conditions as evidence of global warming or cooling are like gamblers seduced by a hot streak into thinking they can beat the house.

Another scientist has tried to point out the stages of climate skepticism that he says many high-profile global warming critics have exhibited sequentially as time passes. John P. Holdren, the head of Harvard’s Program on Science, Technology and Public Policy and a longtime advocate of prompt curbs in greenhouse gases, sent me a note about the reaction he received after the Boston Globe and International Herald Tribune published his opinion piece earlier this month asserting that “climate change skeptics are dangerously wrong.” ( Disclosure: Both papers are owned by The Times’ parent company; keep in mind that opinion columns are sealed off from the news pages).

The centerpiece of the article was Dr. Holdren’s description of the evolving arguments put forward by public figures, including some scientists, challenging climate science as they fight restrictions on greenhouse gases:

Long-time observers of public debates about environmental threats know that skeptics about such matters tend to move, over time, through three stages. First, they tell you you’re wrong and they can prove it. (In this case, “Climate isn’t changing in unusual ways or, if it is, human activities are not the cause.”) Then they tell you you’re right but it doesn’t matter. (“OK, it’s changing and humans are playing a role, but it won’t do much harm.”) Finally, they tell you it matters but it’s too late to do anything about it. (“Yes, climate disruption is going to do some real damage, but it’s too late, too difficult, or too costly to avoid that, so we’ll just have to hunker down and suffer.”)

All three positions are represented among the climate-change skeptics who infest talk shows, Internet blogs, letters to the editor, op-ed pieces, and cocktail-party conversations. The few with credentials in climate-change science have nearly all shifted in the past few years from the first category to the second, however, and jumps from the second to the third are becoming more frequent. All three factions are wrong, but the first is the worst.

Read the rest at the links above. [UPDATE, 5:30 p.m.: John Christy, one of the scientists publicly questioning the evidence for dangerous human-caused climate change, responds below.] After the article ran, Dr. Holdren received a stream of “nastygrams” and wrote a short followup commentary, which has not been published but which he agreed I could post here:


Climate-Change Skeptics Revisited, by John P. Holdren

I did not expect that my op-ed in Monday’s Boston Globe, to which the editors gave the title “Convincing the Climate-Change Skeptics”, would actually convince many skeptics. It was aimed more at reinforcing the resolve of the majority in the public and the policy-making community who, betting on the scientific consensus, are ready to move forward with a serious approach to dealing with the problem but are being slowed down by the ill-founded skepticism of a minority. That is why my own title for the piece was “Climate-Change Skeptics Are Dangerously Wrong”.

I am being castigated by many respondents for resorting to reference to authority rather then providing substantive responses to the specific arguments of climate-change deniers. I suggest that this criticism is in part based on a misunderstanding of what is possible within the length constraint of an op-ed piece. The ”top ten” arguments employed by the relatively few deniers with credentials in any aspect of climate-change science (which arguments include “the sun is doing it”, “Earth’s climate was changing before there were people here”, “climate is changing on Mars but there are no SUVs there”, “the Earth hasn’t been warming since 1998”, “thermometer records showing heating are contaminated by the urban-heat-island effect”, “satellite measurements show cooling rather than warming”) have all been shown in the serious scientific literature to be wrong or irrelevant, but explaining their defects requires at least a paragraph or two for each one.

This cannot be done in the 700 words of an op-ed piece. But there are plenty of other forums where it can be…and has been. Persuasive refutations are readily available not only at a high scientific level in (among others) the reports of the Intergovernmental Panel on Climate Change (ipcc.ch), the UN Scientific Expert Group on Climate Change and Sustainable Development (unfoundation.org/SEG/), the US National Academy of Sciences (dels.nas.edu/globalchange), the US National Center for Atmospheric Research (ucar.edu), and the UK Meteorological Office (met-office.gov.uk) — as well as on a myriad of websites run by serious climatologists (e.g., columbia.edu/~jeh1/, stephenschneider.stanford.edu, realclimate.org ) — but also in a form boiled down for the intelligent layperson by organizations skilled in scientific communication, such as the BBC (news.bbc.co.uk/2/hi/in_depth/629/629/7074601.stm) , the New Scientist magazine (//environment.newscientist.com/climatemyths), and the promising new Climate Central organization (climatecentral.org) featuring The Weather Channel’s climatologist, Heidi Cullen. Any skeptic who actually wants to know what’s wrong with the standard deniers’ arguments can easily find out.

I provided all the above-mentioned references and more in a longer essay on climate-change skepticism that I wrote in June in response to requests for an explanation of the apparent continuing influence of deniers in the U.S. policy process, and from which I abstracted the op-ed I submitted to The Globe. The references wouldn’t fit within the op-ed word limit without losing too much else that I thought needed to be said.

Even more regrettably, I agreed to a further shortening of what I submitted by the editors at The Globe. I regret agreeing to it because it’s clear (from the responses I’m receiving) that the resulting omission of a sentence about the value of skepticism in science left the impression that I am unaware of the positive role that healthy skepticism has played in the scientific enterprise over the centuries. The omitted sentence was in the middle of a passage that in the original read as follows (omission italicized):

All three factions are wrong, but the first is the worst. We should really call them “deniers” rather than “skeptics”, because they are giving the venerable tradition of skepticism a bad name. Their arguments, such as they are, suffer from two huge deficiencies.

As my original reference to “the venerable tradition of skepticism” indicates, I am in fact well aware of its valuable and indeed fundamental role in the practice of science. Skeptical views, clearly stated and soundly based, tend to promote healthy re-examination of premises, additional ways to test hypotheses and theories, and refinement of explanations and arguments. And it does happen from time to time – although less often than most casual observers suppose – that views initially held only by skeptics end up overturning and replacing what had been the “mainstream” view.

Appreciation for this positive role of scientific skepticism, however, should not lead to uncritical embrace of the deplorable practices characterizing what much of has been masquerading as appropriate skepticism in the climate-science domain. These practices include refusal to acknowledge the existence of large bodies of relevant evidence (such as the proposition that there is no basis for implicating carbon dioxide in the global-average temperature increases observed over the past century); the relentless recycling of arguments in public forums that have long since been persuasively discredited in the scientific literature (such as the attribution of the observed global temperature trends to urban-heat island effects or artifacts of statistical method); the pernicious suggestion that not knowing everything about a phenomenon (such as the role of cloudiness in a warming world) is the same as knowing nothing about it; and the attribution of the views of thousands of members of the mainstream climate-science community to “mass hysteria” or deliberate propagation of a “hoax”.

The purveying of propositions like these by a few scientists who do or should know better –and their parroting by amateur skeptics who lack the scientific background or the motivation to figure out what’s wrong with them – are what I was inveighing against in the op-ed and will continue to inveigh against. The activities of these folks, whether witting in the case of the scientists or unwitting in the case of their gullible adherents, have nothing to do with respectable scientific skepticism.

It also needs to be understood by publics and policy makers alike that, while it can never be guaranteed that a mainstream scientific position will not be overturned by new data or insight, the likelihood of this occurring gets smaller as the size and coherence of the body of data and analysis supporting the mainstream position get larger. The lines of evidence and analysis supporting the mainstream position on climate change are diverse and robust – embracing a huge body of direct measurements by a variety of methods in a wealth of locations on the Earth’s surface and from space, solid understanding of the basic physics governing how energy flow in the atmosphere interacts with greenhouse gases, insights derived from the reconstruction of causes and consequences of millions of years of natural climatic variations, and the results of computer models that are increasingly capable of reproducing the main features of Earth’s climate with and without human influences.

The public and the policy makers who are supposed to act on the public’s behalf are constantly having to make choices in the absence of complete certainty about threats and outcomes. If they are smart, they make those choices on the basis of judgments about probability: Which position is more likely to be right? On climate change, the probability is high that the scientific mainstream is right about its main conclusions, even if all the details are not yet pinned down. Those main conclusions are that climate is changing in ways unusual against the backdrop of natural variability; that human activities are responsible for most of this unusual change; that significant harm to human well-being is already occurring as a result; and that far larger –- perhaps catastrophic — damages will ensue if serious remedial action is not started soon.

The rationale for calling the attention of the public and policy makers -– the audiences for an op-ed — to the number, diversity, and distinction of scientists and scientific organizations embracing these conclusions is to inform them of the extent to which this is the view of the most qualified people and groups that have studied the matter. Given the unavoidable fact that most people do not have the training (or the time) to reach an independent conclusion on a scientific matter of this kind, knowing where most of the people who do have the training and who have taken the time come down on the matter is the best guide available on where the public and its policy makers should place their bets.

Comments are no longer being accepted.

Laurie Dougherty August 14, 2008 · 10:07 am

Thanks for posting this Andy (somehow I missed seeing it in my hometown Boston Globe).

The missing piece is the relentless, heavily funded propaganda campaign by the fossil fuel industry that keeps these denialist views in the public eye. That’s a news story that needs to be told.

Steve Bolger August 14, 2008 · 10:12 am

Don’t underestimate the power of narcissism to convince some people that what they wish can become reality if it is wished hard enough by enough people. They don’t understand that nature is utterly indifferent to all human concerns.

Jeff Huggins August 14, 2008 · 10:32 am

Bravo for running this piece here on Dot Earth, Andy.

Well put, Dr. Holdren.

Aside from the actual points and arguments made (they speak for themselves), what I find most interesting is the media’s role here. It sounds like Dr. Holdren’s piece was essentially “raped” and neutered before it got into the papers. (Sorry for that borrowing of terminology.) The Globe’s editors changed, and imposed, a title, and indeed picked a less direct and forceful one. They greatly limited length, apparently requiring the removal of key stuff, references, and etc. They struck an important sentence.

I’m rather sure that Dr. Holdren didn’t submit an encyclopedia, a 200-page textbook, or even a five-page essay. Indeed, I’d bet that what he submitted would have taken up much, much less space than one of those two-page spreads run frequently by ExxonMobil.

(That makes an interesting point all by itself: The Times is most happy to take $150,000 or whatever to run whatever ExxonMobil wants to say in a two-page spread, but it neuters Dr. Holdren’s piece down to a very small fraction of that space, changes the title, and so forth. Of course, I’m not saying that there was conscious wrongful motivation in all that. But, I am pointing out how the “system” did it, and people ARE the system. Let’s look at things and not be blind, folks.)

I can just hear the questions asked by the great grandson of the Globe’s senior editor some decades from now:

“But great grandpa, why didn’t your paper do more to educate the public and help the world do something, before all this had to happen?”

“Well, my precious great grandson, you see, I’m a Journalist, and we Journalists know deep-down that no matter how important or helpful a piece may be, no matter how much truth is in it, there are severe space restrictions. If these restrictions were not set forth by God himself, they were at least defined by the Columbia School of Journalism or drummed into my head somewhere else. So, you see, there was really nothing I could have done. I HAD to edit those words out. Even though, admittedly, your world is a mess now, and it’s the fault of my generation, to this day I still feel that I did the right thing: It’s simply RIGHT to edit those words out and change titles, even if things like that helped to perpetuate our human messing-up of the environment. I’m sure that some philosopher of Journalism somewhere, at some time, said that it was RIGHT to do that. I just can’t recall his name. And, he died a couple decades ago, so he doesn’t have to live with this mess. Good luck, my great grandson. I DO love you.”

“Thanks ALOT! MOOMMMM, do I really, really have to listen to this guy anymore? You told me yesterday that he is a nutcake, and I agree with you.”

Cheers.

lee schipper August 14, 2008 · 10:40 am

I think Prof. Holdren hit the nail about denial and deniers on the head in his original op ed, particularly in view of the kinds of denials I read here.
I’ve know and worked with him for 35 years– the sad thing is we went through all of the same denials as part of the first big national “Study on Nuclear and Alternative energy Systems” run by the US National Academy of Sciences for the Energy Research and Development Administration (now DOE). the whole study was a fight over whether Americans and the US economy could become more efficient or not. The energy industry and its mostly conservative allies maintained that energy needs were fixed by our gross national product’s size. In fact the record shows an enormous improvement in individual efficiencies as well as structural changes that have always been important in shaping energy use. (See my multi sectoral analysis in Energy Policy May 2001.)
The same them haunts the debate today from the “climate is changing but we can’t do much” because of the false believe that energy needs are fixed, therefore CO2 emissions fixed by the CO2 content of energy.
And our experience with higher oil prices have proven once again that people and the economy are flexible.

So would not not be better to try to decide the range of options that maximize our wellbeing (dollars to those who prefer that) for a given amount of energy use or Carbon emissions, rather than ranting on about any one of the arguments that Holdren and so many other reputed, decorated and published scientists have undermined, rather than repeating over and over again the very arguments cum mantrae he mentions
Berkeley CA

Tenney Naumer August 14, 2008 · 10:49 am

Well, it is about time.

Let other scientists come forward and write similar “opinions” in their local papers.

Let it begin. We have very little time, if any.

Edwin Hall August 14, 2008 · 11:13 am

Thank you for including the piece by Holdren, Andy. It is a breath of fresh air. One which I can hope continues to be a fresh breeze blowing through the blogosphere.

Patrick Henry August 14, 2008 · 11:29 am

The last stage of climate denial involves checking the satellite temperature records over the last 20 years, and seeing that the earth is cooler now than in 1988.

At some point the alarmists will come out of denial.

Mike Roddy August 14, 2008 · 11:29 am

Dr. Holden is right, of course, and writes well besides.

As I was reading this, a box appeared on my screen: Ads by Google, featuring “Monkton Debunks Manmade Climate Change!”, and then provides a link. Google, of course, has no specific ties to fossil fuels, and has as its corporate motto “don’t be evil”. The ubiquity of the deniers and their obstinance in the face of the evidence has to be met with forceful and even angry rebuttals. Tea and crumpets “debates” with them won’t do the trick.

Since our political leaders have become corporate marionettes, part of this battle is going to have to be fought with major business interests, excluding the ones like Exxon and Peabody, which are hopeless. Activists need to buy stocks, attend shareholder meetings, and insist that the firm they have invested in stops contributing to the destruction of diverse life on this planet. Many executives outside fossil fuel companies have already figured this out, and need support. High on this list should be utility companies, which are supposed to carry a public trust.

As for Google, I’m going to repeat a quote from Werner Herzog: “Stupidity and evil are the same thing. If you don’t believe me, look into the eye of a chicken.”

Ideally, the media would awaken as well. They do, after all, carry an important public trust. Instead, something like four of the thousand odd questions asked of Presidential candidates during the primaries dealt with climate change- and received stock answers in any case. Plenty of reporters know what needs to be done, but the editors, TV executives, and publishers need to do something that for some reason is becoming rarer: respond to both facts and conscience.

JR August 14, 2008 · 11:31 am

Kudos to the JPL, John Holdren as well as blogs
# 1-5 by Laurie, Steve, Jeff, Lee and Tenney for a brilliant explanation and comments on “Stages
of Climate Denial.”

I especially liked the metaphor by Josh Willis who
described those “who grasp at short term wiggles…
are like gamblers seduced by a hot streak into thinking they can beat the house.”

Many North American geoscience oilpatch professionals and academics who are still gambling against nature are personally well known to me.

Well done, Andy.

Flip August 14, 2008 · 11:34 am

Why is it that if a sceptical thought is expressed the very first thing the “true believers” do is characterize the sceptic. Make ridiculous accusations and then go on to assume there could be NO possible evidence to the contrary of their precious AGW “theory”.

An idea, especially one with supporting evidence should be considered on it’s merits and tested.
Once branding of “hearesy” begins, actual thought stops.

As a sceptic I have reduced my carbon footprint by one third simply to save money. I don’t fit into the last stage of this stupid characterization, and frankly I resent it.

Spencer B. August 14, 2008 · 11:40 am

Some voters remain skeptical about the safety of nuclear power. However, statistics don’t lie. We are enjoying a hot streak with the nuclear generation of electric power.

In the 57 years since the first nuclear plant was built we have only had one meltdown. There are currently about 100 operating plants. About 16 are closed.

So in gaming terms, the chances are about 115 to 1 that no meltdown will occur. Let’s bet the house on Nuclear. We can easily go another 57 years without laying waste to an area the size of Pennsylvania.

In fact, if you jiggle the numbers differently, the odds are 5805 to 1 against a catastrophic accident in a populated area that makes a remote area like Chernobyl look like a microwave accident involving a T.V. dinner. With odds like that, who wouldn’t put his kids up on the crap table as collateral?

We are at Skeptic Stage Three. Yes there was a meltdown and it is agreed there is SOME risk, but it is too costly to ignore using nuclear power.

Americans who are worried about nuclear safety: Stop worrying. We have MIT grads on the job.

John Isom August 14, 2008 · 11:59 am

Dear Dr. Holdren,

Thank you for your elaboration. I second the comments found in the first five posts (the only ones that have cleared so far), and I laud you for wading into the mire of the politics of policy advocacy. Scientific rigor + policy relevance => principled convictions.

Let us hope that, come Wednesday, November 5, we will wake up with a new President who will put in place intelligent people who can read the evidence-writing on the wall, and thereby turn around the last eight years of denial.

That will help to marginalize the talk-show bloviators and denying scientists, a gaggle who will always have their forums, but no longer will have the keys to the decision-making room.

Flip August 14, 2008 · 12:08 pm

If I could offer a conjecture…..

If unequivocal proof were presented today that man does not significanly affect climate, what would happen? (never mind the negative proof issue)

Would such proof be embraced with relief? No.
Would such proof significantly alter the “debate”? No. It couldn’t “the debate is over”, remember?

The “green” version of nature would be declared supreme and the author of the proof excoriated and vilified. The “proof” would be relegated to the blogosphere.

Climate change skeptics have had their jobs and indeed their lives threatened. Reasonable concerns over the IPCC accepted science have been
met with derision and political posturing.

Gore is right about one thing, this is a moral issue.

NeilT August 14, 2008 · 12:13 pm

I will be interested, this summer, to see when Kim goes from “The arctic is not melting, see and the seas are cooling” to “It doesn’t matter it won’t raise sea levels anyway”.

Of course in this particular case it will swing back to “It’s not happening the winter is cold, see”, by January.

Not quite the denialist track being stated above, more a denial pendulum using whatever amunition comes to hand whilst advocating doing nothing. Which is the real problem.

You would think with this years sudden melt down in the arctic during a cooler summer after a more extensive winter regrowth; plus the breakdown of the Wilkins Ice shelf well into the Antarctic Winter/Night at a time of record Antarctic Ice extents, especially at a time of a Solar Minimum, would be enough to put a stop to this once and for all.

However, come March, the guys at Realclimate will be playing a whole new game of “Whack a Mole”.

Which means to me that the people in the denial camp are not being honest with anyone and least of all themselves.

Michael Tobis August 14, 2008 · 12:15 pm

Thanks!

More like this please, and in print too if you could.

Journalism requires making correct judgments about who represents legitimate opinion and who represents malicious propaganda. Abdication of this responsibility is a significant factor in many of the problems we face. We need journalists and editors capable of making such judgments and willing to do so.

The ideal of “balance” is oversimplified and has long been abused by partisan interests. Reporting “both sides” of an issue makes sense in a local public works project when there are valid arguments pro and con. Reporting science and one-sided propaganda as “both sides” of a much more intricate set of overlapping issues does not.

Science still works, and as long as it does should be represented as the moderate middle, not as a pole of a trumped-up debate. If you spread the spectrum far outside the consensus of scientific opinion, you should do it in all directions.

Alarmist challenges to the orthodoxy deserve as much or as little weight as complacent ones, independent of the amount of funding behind them. If there were well-funded extremist alarmism as much as there is well-funded extremist denial, perhaps the public would be as confused as now, but at least the press would get the middle in the right place.

One way to look at the mistake the press is that it is failing to give the alarmist extreme equal coverage with the well-funded complacent extreme. I’d like to see Lovelock quoted every time I see Lindzen. Or one Joe Romm for every Singer. That might help people put matters into a reasonable perspective.

Syl August 14, 2008 · 12:26 pm

#5, Tenney the Tenacious

“We have very little time, if any.”

Sounds like you’ve got one foot in camp 3!

Look, peeps, I’m not now and never have been a ‘denier’ but I am definitely a skeptic about the amount of warming (1)that has occurred and (2) that is attributable to CO2. I’m a skeptic about how much ‘time we have’ before it’s ‘too late’. Our temperatures are not unprecedented and the Hockey Stick is a proven lie as are all the other reconstructions which attempt to resurrect it because they rely on at least one of the infamous proxies used by Mann.

I’m a skeptic when it comes to all the dire predictions coming out of climate models which have been shown to be useless for regional predictions. I’m a skeptic when it comes to scare stories. A recent one claimed that even the current level of CO2 in the atmosphere is acidifying our blood, whereas NASA a few years ago did a study of men in a submarine under conditions with CO2 levels 20-30 times what we have now and it was shown that our blood adjusts within a week.

According to geological records, sea level still has a ways to rise before onset of the next ice age. It’s not good that we may be speeding up the rise at some point, but it still won’t be unprecedented.

I also believe it is impossible to go ‘cold turkey’ and that our national security depends on our independence from foreign oil–thus we need to dig for more of our own resources while we make the transition.

There are other nations on this planet who are in camp 1 and as resources tighten up the world is going to be in danger of a lot of wars. We need to drill here and drill now.

I also believe America CAN and WILL be in the forefront of developing the new technologies we need…as long as we are not crippled so much we lose our engine.

BTW, I noticed Josh Willis used GISS for his chart and Holdren had a nasty condescending tone. Not appreciated.

paminator August 14, 2008 · 12:39 pm

Josh Willis describes those “who grasp at short term wiggles…are like gamblers seduced by a hot streak into thinking they can beat the house.”

This, of course, applies to both supporters and skeptics of the CO2 climate catastrophe hypothesis. It all depends on where you start sampling the climate wiggles, and what wiggle time-frame you choose to define as relevant.

Recent global coolers- 10 years from 1998 El Nino
Anti-CO2 pundits- 30-50 years from 1950-1970 cooling dip
Climate realists- 300 or more years (recognize LIA, MWP, 1500 year cycle)
Cosmo-climatologists- from 1 solar cycle to 100 million years or more
The Weather Channel- 24 hours for heat events :)

[I’m refusing to use Dot Earth Defender v.2.0, a comment filtering/reformatting script, in order to enjoy reading views dissimilar to mine in the Dot Earth comments section.]

Patrick Henry August 14, 2008 · 12:54 pm

“The cornfields of Oklahoma shrivel and fade in a long summer drought. Thick clouds of dust fill the skies, and the farmers tie handkerchiefs over their noses and mouths. At night, the dust blocks out the stars and creeps in through cracks in the farmhouses. During the day the farmers have nothing to do but stare dazedly at their dying crops, wondering how their families will survive.”

The Grapes of Wrath
John Steinbeck – 1939

Concerned citizen August 14, 2008 · 1:09 pm

Dear Patrick Henry:

“The last stage of climate denial involves checking the satellite temperature records over the last 20 years, and seeing that the earth is cooler now than in 1988.”

If you have a peer-reviewed paper authored by scientists who are involved in the collection of said temperature records and which describes this global cooling trend, I’d like to see it. Most of the “analysis” posted on the Web seems to be authored by people who lack thorough understanding of the collected data.

lee schipper August 14, 2008 · 1:18 pm

Patrick Henry, this is preciesly what Holdren was pointing to. Why don’t you explain to us in your words with specific references, not “check the satellite records”, what the global mean average temperature was in 1988, how it moved in the 20 years hence, and what it is today. IN other words, tell us in your words what the evidence is that everyone else is wrong and you are right.

Peter August 14, 2008 · 1:20 pm

Good Job in china team USA, I know the air quality must suck there. Hope to see horton win the gold.
//www.jonathenhorton.com

Matti Virtanen August 14, 2008 · 1:26 pm

Dear Dr. Holdren, you write: “The activities of these folks, whether witting in the case of the scientists or unwitting in the case of their gullible adherents, have nothing to do with respectable scientific skepticism.”

Well, just for the sake of argument, could you come up with any skeptical arguments in climate science that you might consider respectable? Certainly this science has not yet advanced to the point where all skepticism is a sign of disrespect?

Or is there possibly something about “these folks” that annoys you, no matter what they say?

Ike Solem August 14, 2008 · 1:27 pm

Very good piece – but when dealing with the kind of massive public relations campaign being run by the last holdouts (fossil fuel investors, coal companies, and fossil fuel-dependent nation-states), it really is unwise to go along with their “list of questions.”

Even if you did rebut all ten points, it would have little effect on the general public’s understanding of the issue – other than to note that the “ten points” were important enough to merit rebuttal by an expert, so there must still be large uncertainty.

Here are a few basic background points on the issue. Can they be refuted?

1. Current concentrations of atmospheric carbon dioxide and methane far exceed pre-industrial values found in polar ice core records of atmospheric composition dating back 650,000 years.

2. The atmospheric change is due to mainly to human combustion of fossil fuels, but also to large-scale tropical deforestation and wetland removal.

3. The rise in long-lived greenhouse gases (decades to centuries) warms the atmosphere and surface, and that increases the average amount of water vapor in the atmosphere. Water is a short-lived greenhouse gas, as it may form clouds & rain – or it may persist longer as clear-air water vapor.

4. We’ve changed the atmosphere in other ways, mainly by adding ozone and aerosols at the ground, and destroying ozone high in the atmosphere with CFCs. That modifies the radiative forcing.

5. The net effect of the atmospheric changes is to increase the radiation felt at the surface. As the IPCC says, “Observations and models indicate that changes in the radiative flux at the Earth’s surface affect the surface heat and moisture budgets, thereby involving the hydrologic cycle.”

6. Warming over land can have multiple effects, including melting of mountain glaciers, spread of deserts in continental interiors, greater flooding, more frequent heat waves and other extreme weather patterns. Together, that can lead to long-term changes in vegetation cover, biological diversity, and agricultural productivity.

7. In the long run (centuries), persistent warming will also melt the Greenland and Antarctic Ice Sheets, raising sea levels by as much as 50 meters if it all melts. Current sea-level rise rate estimates hover around a 1 meter rise in 100 years.

What are some confirming points that this is all correct? Things that would have to be refuted?

A. The atmospheric instrument record confirms the rate of warming is close to that predicted based on modern knowledge of planetary systems and computer models of the oceans, land and atmosphere.

B. The observed warming is is greatest in the northern polar regions, as predicted. The West Antarctic peninsula has also been warming, but Antarctica as a whole is semi-isolated by the Southern Ocean.

C. Mountain glaciers are in retreat all over the world at low elevations, also matching climate model predictions. The observed melting is greatest at lower elevations, a trend matched in snowpack declines across the Western U.S.

D. The world’s oceans have warmed during this century, accounting for ~80% of the extra absorbed energy. Warming is widespread over the upper layer of the ocean (500 meters or so), and this may change normal ocean circulation patterns, with unforeseen consequences.

There are many other points that climate skeptics would have to refute. Here are several more, from the IPCC:

E. “Both land surface air temperatures and sea surface temperatures show warming. In both hemispheres, land regions have warmed at a faster rate than the oceans in the past few decades, consistent with the much greater thermal inertia of the oceans. {3.2}”

F. “The warming of the climate is consistent with observed increases in the number of daily warm extremes, reductions in the number of daily cold extremes and reductions in the number of frost days at mid-latitudes. {3.2, 3.8}”

Skeptics would have to refute A-F, at least, in order to be believed.

E. O’Neal August 14, 2008 · 1:36 pm

I suppose when there’s no actual warming to point to for over a decade, you need to accuse those who notice this inconvenient truth of “infesting” the public discussion. Harvard prof, I’d love to see you debate one of the scientists you consider vermin, one of “the few with credentials”. But I suspect that, like Hansen and Gore, you’re a loud-mouthed coward.

Spencer B., #11, give it up. Chernobyl was an outdated Soviet design, not properly tested before commissioning, and lacking even a containment building. You might as well compare the Hindenburg to the Goodyear blimp. And I’d rather “have MIT grads on the job” than some nitwit professor from Harvard.