A discussion about global warming

This discussion thread about global warming is posted here not only because it is interesting, but also to get your analysis of this debate.

Background

The comments on the climate change posts on the FM site are similar to those on the posts about the “Dude, Where’s my Recession” meme (here and here).  That meme was a response to exaggerated media pessimism about the economy.  But despite 100+ comments, no specific examples could be produced to support the theory (which I limited to just the print media, to eliminate the “Once I saw on TV” anecdotal evidence).

Here, and in the other posts about climate change on the FM site, we have something similar.  Posts with specific critiques of the case for anthropogenic global warming (AGW), both evidentiary and methodological.  The 160+ comments giving rebuttals almost totally ignore the case for skepticism presented, usually just repeating that AGW deserves a massive public policy response.

A fine example of this is the post about Michael Crichton’s January 2003 speech at the California Institute of Technology (here), which criticized relying on the consensus opinion of science as a guide for public policy.  Several of the comments gave rebuttals relying on the consensus of scientists’ opinion (showing no awareness of the incongruity involved, perhaps because they were writting rebuttals to a text they had not read).

This thread

This post contains an extended dialog lifted from the comments of the two most recent posts about AGW on this site.  The pro-AGW representative is Keith Eric Grant. 

There are 3 reasons this dialog is given as representative of the many comments on the FM site in support of AGW theories.  First, Grant’s background (see below).  Here is an excerpt from the bio on his company’s website.

Keith holds a BS in physics from San Jose State University and an MS and Ph.D. in Applied Science (School of Engineering) from the University of California, Davis. He is now the founder, senior research scientist, and science writer for Ramblemuse Associates. He worked for the Lawrence Livermore National Laboratory (LLNL) from June 1972 until May 2008. His scientific experience includes atmospheric chemistry and and transport modeling, radiation transport, inverse problems, aerosol microphysics and optical properties modeling, nonlinear solver development and applications, climate modeling, satellite data analysis, user consulting, and signalanalysis. … He is a member of the American Geophysical Union (AGU), the Society for Industrial & Applied Mathematics (SIAM), the American Massage Therapy Association (AMTA), the Northern California Science Writers Association (NCSWA), and the National Association of Science Writers (NASW).

Second, the detail of his comments.  Third, his comments illustrate most of the 7 common elements of pro-AGW comments on the FM site, as described in A reply to comments on FM site about Global Warming.

1. Pro-AGW comments often display no signs of having read the skeptics work.
2. Pro-AGW comments often invent assertions which they can easily refute.
3. Pro-AGW comments usually show little or no awareness of the authoritative reports on this issue.
4. Pro-AGW comments usually show little or no knowledge of the long struggle to force some climate scientists to release data and methods.
5. Pro-AGW comments usually show little understanding of the scientific method.
6. They illustrate the pro-AGW faith in computer models.
7. They illustrate the irrationality of the “precautionary principle” as commonly used. 

On to the debate. 

A.  Comments to “Aliens cause global warming”: wise words from the late Michael Crichton

Comment by Keith Eric Grant — 16 November 2008 @ 10:11 pm

In terms of relatively basic physics, there are good reasons to expect that anthropogenic climate change will occur. Human contributions of CO2 into the atmosphere can be estimated from source inventories. CO2 from fossil fuel burning is also depleted in Carbon-14, creating a tracer that is consistent with measurements of isotopes. The estimate of 3.7 W/m2 of forcing (i.e. before any feedbacks) from doubling CO2 isn’t controversial. Quite simply, less heat is initially emitted by the planet to space and it has to come back into balance. A feedback has to involve some increase in temperature to drive other changes. Other changes include increased water vapor (also a greenhouse gas), increased cloudiness, and changes in surface reflectivity. High clouds trap more infrared radiation; low clouds reflect more sunlight back to space. The non-temperature changes imply changes in rainfall and in the geographic and seasonal distribution of rainfall. Balancing energy does not imply no anthropogenic change.

Climate models are physics process models. They represent, to the best implementable approximation, the state of knowledge of the atmosphere. The validity of the various pieces and parts get tested against more exact representations and against data. The documentation and discussion is available, if strewn through decades of literature. Documentation of the physical basis of models is also available. Most research is blind in the sense that it focuses on improving the representation of physical processes. You don’t know the effects on climate model results until much later. Scientific consensus does not mean arbitrary agreement. It means that a lot of scientists in different areas of expertise have both cross-checked (and argued) with each other to the point that they view the treatment is reasonable and appropriate.

Regional climate variations can occur as a result of transport of heat, without a change in the global heat balance. Global change occurs when some factor, anthropogenic or not, changes that balance.

Given an energy forcing from human activities, the best bet is that it will create observable changes in temperature and precipitation — not just in averages but in regional patterns.

The open question is how we limit and mitigate change and how we ensure that the costs are not separated from the benefits. So part of the question arises in how to do the accounting so that costs to the commons are include.

Part of mitigation requires addressing limitations in how human social systems respond and in keeping a functional relationship between observation, including predictive ability, and action. Whereas nomads in the distance past may have responded to north or south migration of rainfall by changing location, people these days get excited by groups of people crossing borders. Climate change can further stress systems of sustenance already under stress. Darfur may be an example, as suggested in an article by Stephan Faris.

A change in rainfall or growing season may mean that a hybrid crop is no longer appropriate in the region for which it was developed. Moving the growing area may involve both changes in terrain and soil-type.

A change in sea-level may mean that some island states become uninhabitable and some current coast cities become to susceptible to weather extremes. The residents of the Maldives are currently shopping for new property.

The bottom line is not that the sky is falling, but that not planning for anthropogenically induced climate change is as unwise as not observing economic and political feedbacks. Missing the opportunity to both plan and mitigate effectively, has its own economic costs and it’s own potential effects on global security. Everything has its indirect costs, including the burning of fossil fuels.

Reply: This is a wonderful comment, perfectly illustrating the fallacies described in my new post A reply to comments on FM site about Global Warming. I think you hit every one!  Two deserve special note.

(1)  “Documentation of the physical basis of models is also available.”

Validation of large climate models requires days or weeks of work by a multi-disciplinary work, esp. if the models are poorly documented code.  The availability of the data is nice, but has anyone funded a 3rd party review of these models?  That should be a prerequiste for the introduction of their output as evidence into the public policy debate.

(2)  The story about the Maldives was also fascinating, noting that the population doubled in the past 20 years from 200 to 400 thousand. What was it during the previous warm spell, the Medieval Optimum, 800 – 1300 AD? Per the Population Statistics website, their population was 50 thousand in 1900 and 30 thousand in 1880. Probably a lot more room per person, even when sea levels were higher. Natural climate cycles can become painful when the population grows 13-fold on a small island.

 B.  Comments to A reply to comments on FM site about Global Warming

#2 — Comment by Keith Eric Grant — 17 November 2008 @ 1:49 am

An interesting list of skeptic’s complaints, but perhaps missing an essential point. Why, if we change the energy balance of the earth should we take as the default assumption that the manner in which the Earth comes back into balance will have little or no consequence?

The physics of the forcing itself are not that complicated. If one is willing to look at only a global average, Manabe and Wetherald provided an answer with a reasonably simple model back in 1967.

You make much of the concept of consensus, but little of the vast published research literature that is the cause for much of the consensus. Atmospheric and oceanic science literature has a long history of publication — much more than any one person can keep up with. The physics that has gone into models has been examined and reexamined. One of the differences between modeling the Earth system and problems such as economics, is that it is inherently a problem of physics, albeit physics too complex to be able to do all details justice and impossible to measure all the details of input. That does not imply that the approximations possible are meaningless.

A good example of this process of science, supposedly ignored, came in the 1990’s when Cess et al. published a study that clouds were “blacker” (i.e. absorbed more) than predicted by theory. Another example occurred when the eruption of Mt. Pinatubo provided an observational opportunityto measure surface temperature sensitivity to radiative changes. Such checking of understanding against observations is a continual process. There is not a simple reliance on models but a reliance on understanding of physics coupled with use of measurement. Yet ultimately, even when all the separate processes are understood, a model may be the only means of exploring the behavior of a complex system with many feedbacks.

In my prior comment I never said that skeptics disbelieve climate change, at least short of groups disbelieving that the world is old enough to have undergone climate change. It was also intentialal that I referred to climate change rather than “global warming”. The warming is only one aspect, albeit a driving one, of the total feedbacks.

And skeptics certainly vary, from those who have legitimate arguments on a specific conclusion (and know the research background) to those who wander in from the side without bothering to gain background. There are equally people who make claims about “global warming” without understanding — sufficient to make my eyes roll.

The problem of detection of an anthropogenic effect from amid the noise is also a separate one from understanding the physics driving both weather and climate. Detection is, in principle, a matter of estimating the level of noise of a trendless system and then estimating the probability of the observed rate and magnitude of change assuming no anthropogenic effects.

I have known few scientist would are unwilling to talk to or work from a standpoint of improving what we understand about how the Earth responds to an energy imbalance. Given that a number of areas of science have become areas of bare survival under the stress of overcommitment of hours, I also well understand an unwillingness to work with those who have a different agenda than improved understanding and even less understanding of the background. I know of few Earth scientist who entered the area from an eagerness to argue with skeptics. Most simply have a driving obsession with figuring out home things work and improving understanding a bit. I suspect that in most areas of human endeavor, those entering a group with the intention of showing how its all being done wrong rather than improving what’s already being done will find their welcome self-limited.

Again, however, increasing the concentration of greenhouse gasses implies creating an energy imbalance that the Earth will respond to. If the weight of 50+ years of atmospheric physics is deemed to provide the wrong answer for the nature of that response, it’s certainly interesting to consider what else will provide a better prediction of how the feedbacks will play out.

For those interested in the physics, something like Piexoto and Oort or Rayner’s Dynamic Climatology are reasonable starts.  Perhaps those skeptical of the science basis can learn more about it while I can take more measure of skeptic’s comments.

Unfortunately, what this mode of a priori discounting of any need for prevention and mitigation seems to preclude is discussion of realistic politicaland social responses that might prove cost effective. Climate feedback to human activities is unlikely to be either a zero or one with nothing in between. That, unfortunately seems to be where the discussion goes, however.

Reply:  There is almost nothing here to reply to.  You must realize that this comment displays most of the characteristics I discuss in my post. You show no evidence that you have read the skeptics work (which does not consist of “complaints”), nor do you mention any of the specifics elements in their case. Your rebuttal essentially discusses a position you have made up, which I guess makes it easy to win a debate (since you are playing both sides).

This statement is esp bizarre: “what this mode of a priori discounting of any need for prevention and mitigation…” This is almost the mirror image of the skeptics actual position.

#8 — Comment by Keith Eric Grant — 17 November 2008 @ 5:07 am

There is indeed more to models than just physics, since all tractable model require approximations. There is a saying that a model should not be more complex than necessary. Neither, however, should it miss important aspects. Between those two lives a lot of tacit knowledge of the modeler.

One other comment I did note: “The concerns about changes in global mean temperature are based on the assumption that the earth is currently at the optimal temperature and that variations over years (unlike variations within days and years) are undesirable.”

This is not necessarily the assumption. I believe that it is more that biological distributions of species and our own social and food production systems are adapted to the current regime. If we create relatively rapid climate change (which involves more than just temperature), then we need be prepared to handle a range of adjustments that cross many national boundaries. It’s not at all clear that we have the social/economic organization to accomplish this. It also requires policy and leadership with timescales beyond 4 years.

The Wegman report also makes an interesting read, BTW.

Reply: Your re-statement is equivalent (with more detail) to the original version in the E&E paper. Optimal means “best” or “most favorable” — the unstated assumption being “for us.” Or in your words, “the current regime.” Otherwise the word has no meaning, except perhaps to a theologian as “best in the sight of God”.

#10 — Comment by Keith Eric Grant — 17 November 2008 @ 6:22 am

Fabius, short of invoking a deity, there can be a distinction. Most favorable/optimal in inherent ability to support life may be different from where we are now — but the transit between the two might be rough, requiring some destruction and resynthesis of current boundaries and infrastructure.

Reply: That’s a valid point. It seems a theoretical one, as you are describing a largely non-existent body of pro-AGW work (both by scientists and laypeople) that make your precise distinction. The Green-Arnstrong phrasing better described the body of actual writings on the subject at this time.

 #13 — Comment by Keith Eric Grant — 17 November 2008 @ 2:05 pm

Pete,  Climate models and weather models are, in terms of physics, converging. One can’t predict weather beyond about a week, because it involves matching particular storms in particular places starting from imperfect initial conditions and an approximate model. Climate, however, is essentially the long-term statistical envelope of weather. Thus it’s a matter not of timing, but of catching the mean and variability of circulation and precipitation. Tim Palmer recently wrote Predictability of Weather and Climate should anyone be interested.

#17 — Comment by Keith Eric Grant — 17 November 2008 @ 4:40 pm

Greg Panfile’s comment hits part of the issue. It is a relatively simple matter to calculate the energy forcing from greenhouse gases. That forcing is not particularly controversial. What complicates the matter is that heating from the initial forcing changes the amount of water vapor in the atmosphere, which is also a strong greenhouse gas. Water vapor change also leads to changes in clouds, which can either heat or cool depending on the altitude. Others, such as the Pielkes and Petr Chylek believe that other factors such as land use changes aren’t being fully considered. Roger Pielke, Sr. has his own Climate Science blog.

In constrast, the Climate Audit and the Wegman report (linked from the Audit) focus on problems in Mann’s analysis of paleoclimate data. The Wegman report notes that the data set “does not provide insight and understanding of the physical mechanisms of climate change” and that “What is needed is deeper understanding of the physical mechanisms of climate change”. In short, the data set is about detection of change. Pielke et al. are discussing mechanisms.

Reply:   I agree on all points!  What spins the debate out of control IMO is the poor temperature record of modern times — up to and including today; both ground, atmosphere, and satellite. Without reliable current data to anchor the debate, everything becomes a moving target. See the previous comment for a specific example of this.

Also note the Wegman and North reports validate many of the skeptics concerns about the historical temperature records created by the pro-AGW scientists use of proxy data.  So we have poor data and limited understanding of the physical mechanisms.  A weak basis for expensive policy action.

#18 — Comment by Keith Eric Grant — 17 November 2008 @ 6:03 pm

Admittedly, a lot could be done to better data quality. Policy and funding are often thin and inconsistent which coupled with parochialism in college departments (Wegman report notes that statisticians at same university weren’t consulted) doesn’t help. Gaps in funding for satellites, leading to delays in launching instruments, leading to lack of overlap in measurements also doesn’t help. This was a problem several year back in solar cycle monitoring. The solar cycle effects are not simply ignored, btw. People like Judith Lean have been looking and writing about them for years, including in Science.

Reply: Your comments are fascinating. Intelligent and knowledgeable replies to made-up statements. It’s an unusual combination.

“The solar cycle effects are not simply ignored, btw.”

To what does this refer? My only mention of solar cycles on this thread is “Many of the pro-AGW comments here discuss cartoon-like models of earth’s climate (co2 only), to show that AGW is obvious. These ignore important issues of magnitude and feedbacks, not to mention other factors (e.g., solar cycles). ” I doubt Dr. Lean (bio) has posted any comments on this site.

I suggest you look at sections 1, 2 and 3 on the FM reference page about Science, Nature, and Geopolitics. You will see that the FM site has 4 posts about the current solar cycle, lists 5 sites with current coverage, and links to 9 articles on the subject.

On a different note, re your statement “Policy and funding are often thin and inconsistent which coupled with parochialism in college departments…” NASA and NOAA claim to do rigorous quality control on the surface temperature data, a high priority system vital to climate-related public policy. However, events have shown this to be false (see this, for example). I doubt lack of funding is the problem, given the relatively tiny sums required.

#24 — Comment by Keith Eric Grant — 18 November 2008 @ 12:09 am

FxConde, the Earth, ultimately, will not terribly care what the level of CO2 is. There have been times in the past in which the diversity of life dropped greatly, but eventually, the Earth moves on. The question as to “safe” depends on the definition of “safe for what?”. Perhaps Hansen is simply saying that beyond that mark humans will have to make accommodations for a climate change we produce. This would be based on the underlying physics, not measurements aimed at detection.

A change in the global annual mean temperature doesn’t speak to regional change, one of the points that Pielke makes. Warmer temperatures can mean longer growing seasons, more snowfall in some areas, or a crop of dryland wheat killed by heat before the rains come. It can also mean a winter snowpack that instead falls as rain and runs off in floods long before it’s needed in the middle of summer. The estimate of global temp. change for doubling CO2, without any other feedbacks is about 1.1 deg C. With other feedbacks, it ranges between 1.6-4.5 deg C with most bets in the 2-3 deg range. The water vapor bit was surveyed in an “Insight” series put out by Nature. That doesn’t say a thing about anybodies own backyard.

Reply: While I agree the remark about “the Earth” is silly rhetoric (something that pollutes both side of this debate), I suspect FxConde refers to the broad historical pattern. The Little Ice Age was a bad time for many northern hemisphere societies, due to repeated crop failures. The warmer “medieval optimum” was on the whole a better time, food-wise. Several noted agricultural experts have expressed concerns about the effect of possible cooling period, given the very low levels of global grain stockpiles (in terms of days-demand, or per capita demand).

For more on this, see the posts and links to other sources on the FM Reference Page about Food – articles about this global crisis.

#25 — Comment by Keith Eric Grant — 18 November 2008 @ 2:28 am

Fabius, that comparison between the Little Ice Age and medieval optimum makes sense. A warmer global temperature might conceivably support more food production then we accomplish now. But than goes back to my earlier comments about being adapted to the present versus what might be “optimum” — there could still be adaptions in human systems and shifts in rainfall patterns between the two. Some tropical diseases and other pests could also find new ranges.

Recent warming years, whatever the immediate cause, have extended the range of pine beetles, first into British Columbia and then jumping into Alberta. Science writer Charles Petit did a profile on a person looking at the connection between bears and whitebark pines. A recent CBC news report says the infestation may be tapering off, only because the beetles have run out of food. Cold winters kill off the beetles, previously limiting their range.

None of this is unprecedented or the end of the world. Any choice, however, is going to have trade-offs. It’s the comments like one made some years back by a Republican Congressman, “Warmer? I wouldn’t mind a few airports being warmer in the winter.”, that reveal when decisions are made without having a clue or a care.

Reply: There are many questionable assumptions embedded in your comment about making “choices”.

• That we understand climate processes sufficiently well to draw reliable conclusions.
• That current changes are above the magnitude of “background” noise or natural variation in climate.
• That we have the ability to affect these trends.
• That we can do so at some possible cost.

Only the latter brings the element of choice into the picture. We are IMO a long way from that point in the decision-making process.

The beetle story is interesting, but then these days the path to government funding seems to require a link to climate change.  Reading the general media it seems that all change results from climate change, including earthquakes.

 #26 — Comment by Keith Eric Grant — 18 November 2008 @ 4:08 am

I hadn’t realized when I wrote earlier about bark beetles, BTW, that they are featured in today’s NY Times.

In 1967, Manabe and Wetherald did a simple study on the energetics, using a radiative-convective model. If they assumed that absolute water vapor was constant, the got a 1.3 deg C change in global average temperature. If they assumed that relative humidity were constant, they got a 2.3 deg change. Both observationally and from consideration of how evaporation, convection, latent heat release, the temperature lapse rate, and radiation to space are tied together, the relative humidity assumption is more likely to be correct. Modern climate models don’t assume relative humidity, but in relating the variables listed above they come close to predicting constant relative humidity. Temperature changes following the Mt Pinatubo eruption also seem to satisfy this.

So, from fairly basic considerations, this order of temperature change is very feasible if not likely. This says nothing about geographic details or how the planet will distribute such change or about our ability to detect change from under the background of noise. The result, however, is neither trivial nor dumb-minded.

We make a choice whatever we do. Choosing not to choose is also a choice. I’m not suggesting what policy is possible, but that we do need to take the issue seriously enough to look at policy. Right now the southern part of California has been “infested” with fires, as central California has t-shirt weather. Whether anthropogenic or not, this is a climate variation event. Do we handle such events as isolated incidents or do we notice patterns and do more coordinated planning? As one level, this is the same kind of planning that should be done as to earthquakes or hurricanes. Do what we can to prevent damage, do what we can to mitigate damage, and have some preparation to handle people who need assistance or relocation. Look at the security considerations from what might occur in other countries.

Reply: You repeat and repeat that we must do this and must do that. I prefer to wait for some decent data and analysis by 3rd party authorities, and consider it folly to act in advance of these things. You are free to donate funds to charities that can put your ideas into action.

The California fires — an issue I am familar with — is poor evidence of the need for “policy action” to fight AGW, as they almost certainly result from normal climatic variation. Much of the American southwest is prone to long droughts. That you cite as evidence in the AGW debate re-enforces my point about the need for better understanding of these things before policy action.

I do not see that you have acknowledged — or even read — any of the points I have raised. This is not only discouraging, but also diminishes my confidence in what you say. I feel like I am talking with a cultist handing out tracts at the airport.

#28 — Comment by Keith Eric Grant — 18 November 2008 @ 6:27 am

Fabius, I’ll quit repeating and simply thank you for hosting an interesting discussion and pointing to some interesting pieces to read. And yes, perhaps being a physicist (among other things) is a bit like being a cultist. Apart from that, I’ll look forward to seeing your thoughts in the other areas you cover.

Reply: Being a physicist is not at issue; your statement is hardly fair or reasonable.

You have made 10 comments, very polite but distinguished by an unwillingness or inability to respond to the data and reasoning given in either the post or the replies. Each comment ignores the reply and shifts to a new subject.  This is a characteristic of cultists, even if you were Einstein. Also remarkable is that you do not explain the several instances in which your “replies” do not match anything said on this thread.

You repeatedly assert that policy action is needed, despite the deficiencies in pro-AGW case. To mention just a few: the inadequate quality control in the surface temperature data, cherry-picking when selecting of historical proxies, and the lack of outside review of the key computer models. These are serious critiques of the data and methods of the pro-AGW theories, none of which can be waved away with the “I’m a physicist” defense.

My comment about repeating was an invitation to provide a response, or point to some relevant analysis or data. Responding to nine comments with no sign that you have read them would tax the patience of a better man than I.

#29 — Comment by Fabius Maximus — 18 November 2008 @ 7:11 am

Should the government act before we understand the dynamics of AGW? Here is a historical case study.

The Black Death challenged the people and governments of that time to an extent beyond anything in our time. They responded with many strong measures. One was killing the dogs, suspected of causing or spreading the disease. This was easily done, but proved counter-productive. The dog’s fleas found new hosts, often people. Also, dogs were important in limitign the rat population.

Something similar happened recently in Sura, India (source).  The equivalent today might be drastic measures to limit the growth of atmospheric CO2 — at great cost — while the Earth enters a cooling cycle.  Action without understanding can have unpleasant results.

#32 — Comment by Keith Eric Grant — 18 November 2008 @ 5:53 pm

Fabius, my comment about being a physicist was in response to your comment about being “an airport cultist”. There is a perceptual change that occurs such as discussed by Gary Klein in “Sources of Power”. You have stated that you wish to wait for positive detection of “AGW” to believe in it. You point to critics of the data and processing of data leading to the IPCC claim of such detection.

That is a different kind of “skepticism” from that which is voiced by an atmospheric physicist such as Roger Pielke, Sr., who also has his differences with the IPCC. Pielke is claiming that the proper term should be climate change, not global warming because global warming is meaningless as to it’s effects on people, most of which are regional. Pielke does not criticize models for their lack of ability to obtain global numbers, but for their inability to make correct regional predictions. He criticizes the IPCC, not for believing in anthropogenic climate change, but for placing all the emphasis on curtailing greenhouse gas emissions while ignoring the climate effects of other anthropogenic activities. He looks, for example, at how deforestation in the Amazon can impact rainfall in the American midwest, an effect called a teleconnection. He points to his recent policy statement on the broader role that humans have in affecting climate. In short, Pielke is operating from a much broader range of data and experience than one can obtain from IPCC. I doubt that he would argue with the 2-3 deg estimate of global surface temperature change from doubling CO2, but would respond that such a number says nothing of the winners or loser or the response required from humans. Pielke also links, from several of his pages, to a National Research Council report on Radiative Forcing of Climate Change.

In short, both Pielke and I are operating from a different perspective than detection of global warming, which is, in our context, an interesting side-note to the effects of human activities. Our interest is more in the energetic driving of change and how various human activities create significant feedbacks. Pielke’s perspective is essentially one of human activities inescapably changing regional climates. His call is not for ignoring policy, but for broadening policy to deal with changes beyond trace gas emissions, in essence because anthropogenic climate change is inescapable.

This is a different perspective than the one that you profess, one coming from years of looking at terrestrial interactions and an understanding of how they constrain each other. It is also the manner in which someone like Pielke differs from Crichton.

Reply: Another change of subject.  Every new comment ignores the replies, and drifts to another marginally related subject.  That gives this dialog the “debating a cultist” tone.

(1)  “This is a different perspective than the one that you profess, one coming from years…”

While this can be described as a different “perspective”, it is more accurately described as a different analytical question. Certainly an interesting and important one, but not relevant (except tangentially) to the question under discussion. It’s a big world, with many questions. This is why the comment policy asks that comments be related to the specific post. Unless the domain of a discussion is focused, I have found that discussions either collapse into mutually unintelligible babble — or just peter out from topic drift.

(2)  “I doubt that he would argue with the 2-3 deg estimate of global surface temperature change from doubling CO2.”

As Steve McIntyre has noted so many times, that number is endless repeated in the climate sicence literature — but with very little analytical or empirical support.

For more information from the FM site

To read other articles about these things, see the FM reference page on the right side menu bar.  Of esp relevance to this topic:

• Posts about Science, Nature, and Geopolitics— this lists not only posts on the FM site, but also a wide range of other online sources.

Posts on the FM site about climate change:

1. A look at the science and politics of global warming, 12 June 2008
2. Global warming means more earthquakes!, 19 June 2008
3. An article giving strong evidence of global warming, 30 June 2008
4. Worrying about the Sun and climate change: cycle 24 is late, 10 July 2008
5. More forecasts of a global cooling cycle, 15 July 2008
6. Update: is Solar Cycle 24 late (a cooling cycle, with famines, etc)?, 15 july 2008
7. Two valuable perspectives on global warming, 4 August 2008
8. President Kennedy speaks to us about global warming and Climate Science, 7 August 2008
9. Solar Cycle 24 is still late, perhaps signalling cool weather ahead, 2 September 2008
10. Update on solar cycle 24 – and a possible period of global cooling, 1 October 2008
11. Good news about global warming!, 21 October 2008
12. One of the most interesting sources of news about science and nature!, 27 October 2008
13. “Aliens cause global warming”: wise words from the late Michael Crichton, 15 November 2008
14. A reply to comments on FM site about Global Warming, 17 November 2008

Afterword

If you are new to this site, please glance at the archives below.  You may find answers to your questions in these.

Please share your comments by posting below.  Per the FM site’s Comment Policy, please make them brief (250 words max), civil, and relevant to this post.  Or email me at fabmaximus at hotmail dot com (note the spam-protected spelling).