Climate Skeptic

Earth Day Thoughts

Cross-Posted from Coyote Blog

Happy Birthday Vladimer Lenin Earth Day.  I have a few thoughts for the day:

Sucking the Oxygen Out of the Environmental Movement

Observe today how little of the discussion is about anything other than climate.  There are still many environmental issues in the world that can be improved by the application of man's effort and technology -- unfortunately, climate is the least of these but the issue getting the most attention.  Consider how the global warming panic has sucked the oxygen out of the environmental movement.  Ten years from now, I predict that true environmentalists will be looking back on the hysteria over trace amounts of CO2 in the atmosphere as a huge setback for real environmental progress.

Environmentalism and Socialism

If you attend any Earth Day events today, notice how many of the speeches and presentations and such are anti-corporate, anti-trade, anti-capitalist, anti-wealth screeds, and have little to do with the environment.  If you actually go to a live Earth Day event, you will see why the selection of Lenin's birthday was no accident.  You will not see this on the network news, because the media is sympathetic to the environmental movement and tends to edit the socialist rants out as PR protection for the environmentalists, knowing that American audiences would lose sympathy for them if they listened to the whole package. (This is mostly an American phenomenon - I have found from my brief travels in Europe that the media there does less such editing, perhaps because they know their audience is more comfortable with socialism).

The Climate Denier Trick

There are a lot of reasons not to be worried about "inaction" on global warming.  To justify the enormously expensive cuts in CO2 productions, on the order of 80% as supported by Obama and Clinton, one has to believe every element of a five-step logic chain:

1. Mankind is increasing CO2 concentrations in the atmosphere
2. Increased atmospheric CO2 causes the world to warm (by some amount, large or small)
3. The increases in CO2 from man will cause substantial warming, large enough to be detectable above natural climate variations
4. The increases in world temperatures due to man's CO2 will have catastrophic impacts on civilization
5. These catastrophic impacts and their costs are larger than the enormous costs, in terms of poverty and lost wealth, from reducing CO2 with current technologies.

Climate alarmists have adopted a rhetorical trick that no one in the media seems willing to call them on.   They like to wage the debate over global warming policy on points one and two only, skipping over the rest.  Why?  Because the science behind numbers one and two are pretty strong.  Yes, there are a few folks who will battle them on these points, but even very strong skeptics like myself accept points one and two as proved. 

Here are some examples of how this trick works.  If, like me, you do not accept steps 3-4-5 in the above logic chain, you will be called a "denier."  When asked what a denier means, a climate alarmist will often position this denial as somehow disputing #1 and #2.  On the other hand, if one publicly accepts #1 and #2, the alarmist will shout "QED" and then proceed to say that strong action on CO2 is now justified.  When an alarmist says that the a consensus exists, he is probably correct on points 1 and 2.  But he is absolutely incorrect that a consensus exists on 3-4-5.

Don't believe me?  Think back to the early Republican debate, where the moderator asked for a show of hands whether [I can't remember the exact question] man was causing global warming.  The implication is that you either have to accept this whole logic chain or not.  One can see why Fred Thompson begged to have 90 seconds to explain his position, and why the moderator, presumably in the alarmist camp, denied it to him. 

Over the last year or two, skeptics have gotten a lot better at making their argument.  Most all of them, like I do, begin their arguments by laying out a logic chain like this and explaining why one can believe that man-made greenhouse gases cause warming without accepting the need for drastic climate action.  The result?  Alarmists have stopped debating, and/or have declared that the debate is "over."  Remember that last great Al Gore climate debate?  Neither do I.

The Single Best Reason Not To Be Worried About Climate

I could, and have, in my books and videos, made arguments on many points in 3-4-5 (links at the bottom of the post).  In four, no one ever considers the good effects of warming (e.g. on growing seasons and crop yields) and most every other problem is greatly exaggerated, from hurricane formation to sea level rises.  And in five, every time someone has tried to put a price on even small reductions in CO2, the numbers are so enormous that they are quickly suppressed by a environmentalist-sympathetic media.  Suffice it to say that even the climate-sanctimonious Europeans have not been willing to pay the price for even slowing down their CO2 growth (which has risen faster than in the US), much less reducing it.

But in this logic chain, there is little need to argue about four and five if #3 is wrong.  And it is.

The effects of CO2 acting alone on temperatures are quite small -- And everyone, even the alarmists, agree!  A doubling of CO2 concentrations, without other effects that we will discuss in a moment, will heat the earth no more than about 1 degree Celsius (though several studies recently have argued the number is much less).  This is not some skeptic's hallucination -- this is straight out of the IPCC third and fourth assessments [IPCC text quoted here].  In fact, the IPCC in their reports has steadily reduced their estimate of the direct contribution of CO2 on temperatures.  CO2, acting alone, warms the Earth only slowly, and at this rate we would see less than a degree of warming over the next century, more of a nuisance than a catastrophe.

But some scientists do come up with catastrophic warming forecasts.  They do so by assuming that our Earth's climate is dominated by positive feedbacks that multiply the initial warming from CO2 by a factor of three, four, five or more.  This is a key point -- the catastrophe does not come from the science of greenhouse gases, but from separate hypotheses that the earth's climate is dominated by positive feedback. This is why saying that greenhouse gas theory is "settled" is irrelevant to the argument about catastrophic forecasts.  Because these positive feedbacks are NOT settled science.

In fact, the IPCC admits it does not even know the sign of the most important effect (water vapor), much less its magnitude.  They assume that the net effect is positive, and in fact strongly so - on the order of 60-80% feedback or more, nearly unprecedented numbers for a long-term stable physical system [more on feedback and its math here].  This is particularly ironic because alarmist Michael Mann, with his hockey stick, famously posited that temperatures over the last 1000 years were incredibly flat and stable until man started burning fossil fuels, a proposition that is hard to believe if the climate is dominated by strong positive feedback.   Note that when people like Al Gore say things like "tipping point," they are in effect hypothesizing that feedback is greater than 100%, meaning that climate can be a runaway process, like nuclear fission.

In fact, with the 100 or so years of measurements we have for temperature and CO2, empirical evidence does not support these high positive feedbacks. Even if we assign all the 20th century warming to CO2, which is unlikely, our current warming rates imply close to zero feedback.  If there are other causes for measured 20th century warming other than CO2, thereby reducing the warming we blame on CO2, then the last century's experience implies negative rather than positive feedback in the system.  As a result, it should not be surprising that high feedback-driven forecasts from the 1990 IPCC reports have proven to be way too high vs. actual experience (something the IPCC has since admitted).

However, climate scientists are unwilling to back down from the thin branch they have crawled out on.  Rather than reduce their feedback assumptions to non-catastrophic levels, they currently hypothesize a second man-made cooling effect that is masking all this feedback-driven warming.  They claim now that man-made sulfate aerosols and black carbon are cooling the earth, and when some day these pollutants are reduced, we will see huge catch-up warming.  If anything, this cooling effect is even less understood than feedback.  What we do know is that, unlike CO2, the effects of these aerosols are short-lived and therefore localized, making it unlikely they are providing sufficient masking to make catastrophic forecasts viable.  I go into several reality checks in my videos, but here is a quick one:  Nearly all the man-made cooling aerosols are in the northern hemisphere, meaning that most all the cooling effect should be there -- but the northern hemisphere has actually exhibited most of the world's warming over the past 30 years, while the south has hardly warmed at all.

In sum, to believe catastrophic warming forecasts, one has to believe both of the following:

1. The climate is dominated by strong positive feedback, despite our experience with other stable systems that says this is unlikely and despite our measurements over the last 100 years that have seen no such feedback levels.
2. Substantial warming, of 1C or more, is being masked by aerosols, despite the fact that aerosols really only have strong presence over 5-10% of the globe and despite the fact that the cooler part of the world has been the one without the aerosols.

Here's what this means:  Man will cause, at most, about a degree of warming over the next century.  Most of this warming will be concentrated in raising minimum temperatures at night rather than maximum daytime temperatures  (this is why, despite some measured average warming, the US has not seen an increase of late in maximum temperature records set).  There are many reasons to believe that man's actual effect will be less than 1 degree, and that whatever effect we do have will be lost in the natural cyclical variations the climate experiences, but we are only just now starting to understand.

To keep this relatively short, I have left out all the numbers and such.  To see the graphs and numbers and sources, check out my new climate video, or my longer original video, or download my book for free.

Update: Very relevant article by Roy Spencer on the over-estimation of feedback in climate models.

Many of us, especially those who were trained as meteorologists, have long questioned the climate research community’s reliance on computerized climate models for global warming projections.  In contrast to our perception that the real climate system is constantly readjusting to internal fluctuations in ways that stabilize the system, climate models built upon measured climate behavior invariably suggest a climate system that is quite sensitive - sometimes catastrophically sensitive — to perturbations such as those from anthropogenic greenhouse gas emissions.  Unfortunately, it has been difficult to articulate our ‘hand-waving’ concerns in ways that the modelers would appreciate, i.e., through equations.   

After years of pondering this issue, and after working on our two latest papers on feedbacks (Spencer et al., 2007; Spencer and Braswell, 2008, hereafter SB08), I believe that I can now explain the main reason for this dichotomy.   Taking the example of clouds in the climate system, the issue can be introduced in the form of a question:

To what extent are climatic variations in clouds caused by temperature change (feedback), versus temperature change being the result of cloud variations? 

I Will Accept this Description

I think this description fits where I am pretty well:

Lawrence Solomon, a columnist for Canada’s National Post—and the victim of an earlier smear campaign—decided to ask who these “deniers” really are and what they really believe. What he found is telling: “Among all the deniers I have profiled,” Solomon writes, “I have never encountered one who disputes that there is such a thing as a greenhouse effect, or that carbon dioxide is a greenhouse gas.... The arguments are all about how powerful the effect is, especially when considered in combination with other factors, various feedback mechanisms both negative and positive, and other influences that might or might not overwhelm the effect of CO2.” In other words, Solomon found that the “deniers” are, in fact, not in denial at all. They are merely dissidents from the political orthodoxy of climate catastrophism.

Winning Video

My 3-minute climate video won second place in the Kids and Globaloney contest. 

The results surprise me a bit.  I found the 3-minute limit almost impossible to make work in the video contest, and thought my video, which I include below, was rushed.

A better version is the 9-minute version here which covers the same subjects but with a bit more leisure and explanation.  This video, however, is a bit dated.  As I write in the YouTube comments, I want to take a better shot at explaining the issues around positive feedback.  I think I can fix it with just a rewrite of the narration.  That longer video is here and below.

My really long video, 60-minutes in 6 parts, is here.

The Keystone Issue of Global Warming

It is silly to argue whether CO2 in the atmosphere can cause global warming: It clearly does.  The issue is not "if" but "how much".  The warming from man's CO2 might be 8 degrees in a century, as Al Gore might argue, in which case man's CO2 would be incredibly disruptive.  Or it might cause just a few tenths of a degree of warming, which might be unnoticeable within the noise of natural climate variation.

Interestingly, the key to understanding this issue of the amount of warming does not actually lie in greenhouse gas theory.  Most scientists, skeptics and alarmists alike, peg the warming directly from CO2 at between 0.3 and 1.0 degrees Celsius for a doubling in CO2 levels  (this notion of how much temperatures would increase for a doubling of CO2 levels is called climate sensitivity).  If this greenhouse gas warming was the only phenomenon at work, we would expect man-made warming over the next century even using the most dire assumptions to be less than 1C, or about the same amount we have seen (non-catastrophically) over the last century.  Warming forecasts of this magnitude would not in any way, shape, or form justify the draconian economic impacts of many current government carbon reduction proposals.

The key, as I have written before (and here), lies not in greenhouse gas theory itself but in the theory that the earth's climate is dominated by positive feedback.  This theory hypothesizes that small changes in temperature from greenhouse gas increases would be multiplied 3,4,5 times or more by positive feedback effects, from changes in atmospheric water vapor to changing surface albedo.

Let me emphasize again:  The catastrophe results not from greenhouse gas theory, but from the theory of extreme climactic positive feedback.  In a large sense, all the debate in the media is about the wrong thing!  When was the last time you saw the words "positive feedback" in a media article about climate?

Christopher Monckton has an absolutely dead-on post at Roger Pielke's blog about this feedback theory that I want to excerpt in depth.

This chart is a good place to start.  It shows the changes in the IPCC's estimate for climate sensitivity to CO2 and how it has changed over the course of the reports.  More importantly, he splits the forecast between the amount due directly to Co2, and the amount due to the multiplicative effect of positive feedback.  The green bar is the direct contribution of Co2, and the pink is the feedback.

We can observe a couple of things.  First, the IPCC's estimate of the amount of warming due to CO2 directly via the greenhouse gas effect has actually been going down over time.  (Note that there are those, like Richard Lindzen, who suggest these numbers are still three times too high given that we have not observed a difference in surface and lower troposphere warming that greenhouse gas theory seems to predict).

Second, you will see that the IPCC's overall forecasts of climate sensitivity have been going up only because their estimates of positive feedback effects have gone way up.  The IPCC assumes that feedback effects multiply warming from CO2 by three.  And note that the IPCC's forecasts of feedback effects trail those of folks like James Hansen and Al Gore. 

So how confident are we in these feedback effects?  Well, it turns out we are not even sure of the sign!  As Monckton writes:

The feedback factor f accounts for at least two-thirds of all radiative forcing in IPCC (2007); yet it is not expressly quantified, and no “Level Of Scientific Understanding” is assigned either to f or to the two variables b and κ upon which it is dependent....

Indeed, in IPCC (2007) the stated values for the feedbacks that account for more than two-thirds of humankind’s imagined effect on global temperatures are taken from a single paper. The value of the coefficient z in the CO₂ forcing equation likewise depends on only one paper. The implicit value of the crucial parameter κ depends upon only two papers, one of which had been written by a lead author of the chapter in question, and neither of which provides any theoretical or empirical justification for the IPCC’s chosen value. The notion that the IPCC has drawn on thousands of published, peer-reviewed papers to support its central estimates for the variables from which climate sensitivity is calculated is not supported by the evidence.

Given the importance of feedback to their forecasts, the treatment in the latest IPCC report of feedback borders on the criminal.  I have read the relevant sections and it is nearly impossible to find any kind of discussion of these issues.  A cynical mind might describe the thousands of pages of the IPCC report as the magician grabbing your attention with his left hand to hide what is in his right hand.  And what is being hidden is that ... there is nothing there!  Feedback is the pivotal point on which the whole discussion of drastic carbon abatement should turn and there is nothing there. 

Monckton goes further, to point out that hidden in the IPCC numbers lies an absurdity:

if the upper estimates of each of the climate-relevant feedbacks listed in IPCC (2007) are summed, an instability arises. The maxima are -

Water vapor 1.98, lapse rate -0.58, surface albedo 0.34, cloud albedo 1.07, CO₂ 0.57, total 3.38 W m^-2 K^-1.

The equation f = (1 - bκ)^-1 becomes unstable as b → κ^-1 = 3.2 W m^-2 K^-1. Yet, if each of the individual feedbacks imagined by the IPCC is increased to less than the IPCC’s maximum, an instability or “runaway greenhouse effect” is reached.

Yet it is reliably inferred from palaeoclimatological data that no “runaway greenhouse effect” has occurred in the half billion years since the Cambrian era, when atmospheric CO₂ concentration peaked at almost 20 times today’s value

Positive feedback can be weird and unstable.  If there is enough of it, processes tend to run away (e.g. nuclear fission), which is what Monckton is arguing that some of the IPCC assumptions lead to.  Even when feedback is less positive, it still can cause processes to fluctuate wildly.  In fact, it is fairly unusual for long-term stable processes like climate to be dominated by positive feedback.  Most scientists, when then meet a new process, would probably assume negative feedback until proven otherwise.  This is a particular issue in climate, where folks like Michael Mann have gone out of their way to argue that the world temperature history over the last 1000 years before man began burning fossil fuels is incredibly stable and unchanging.  If so, how can this be consistent with strong positive feedback?

Anyway, there is a lot more numerical detail in Monckton's post if you want to dig into the equations.

I would add one thing to his analysis:  If you look at the last 100 years of history, the change in temperature given the observed change in CO2 levels comes no where close to a climate sensitivity of 3 or more, even when you assign all historical warming to CO2 rather than other effects like the sun.  In fact, as I showed in this analysis, climate sensitivity appears to be 1.2 when one assigns all past warming to CO2, and something well less than that if one accepts the sun and other effects also play a role.  These historical analyses would point to feedback that is either zero or negative rather than positive, more in line with what one would expect from complex natural systems.

You can see a discussion of many of these topics in the video below:

What He Said

John Atkinson, via Tom Nelson, mirrors many of my thoughts on climate models:

The scientists who interest me in this field are those who can draw on the experience of a lot of people who have come before them. And uniformly in these areas I find scepticism. People who write mathematical models of complex systems for a living tend to find the climate models very unconvincing. Geologists find the arguments very unconvincing. Engineers find the arguments unconvincing. And astrophysicists find the arguments unconvincing....

The climate models seem to be largely driven by over-fitting to a small sample set and positive feedback. The small sample set - at most 30 years of accurate data - might be enough to try and predict one or two years, but 50 year predictions? Ignoring the biggest effect on global warming - water vapour - is surely going to cause problems.

Positive feedback in engineering invariably results in unstable systems - so we have to ask why do most if not all of the climate models rely on it to get doomsday predictions? For the Earth to have survived as long as it has with a stable climate, through major events like ice-ages or volcanic eruptions, there is little doubt that a degree of negative climate feedback is essential.

Some General Thoughts

I have been getting a lot of new readers of late, including a number of commenters who disagree with me fairly strongly.  Welcome.  Here are some general thoughts:

1. Excepting some ads for Viagra and cell phones, I have never and will never delete a comment on this site.  Folks are welcome to fill up the comment threads with contrary opinions. For those distrustful of the motives of skeptics, may I observe that sites like RealClimate cannot make this claim and routinely flush comments that don't agree with the local prevailing doctrine, so make of that what you will.
2. I almost never respond to comments in the comment thread itself.  I like to think about and digest the comments for a while, and then incorporate them or respond to them in later posts.  Trying to respond in real time in comment threads results in flame wars, not reasoned discussion. 
3. Unlike many skeptics, I accept that atmospheric CO2 produced by man can warm the earth.  The IPCC and most climate scientists believe that the greenhouse gas effect alone may warm the earth about a degree over the rest of this century, an amount that would be a nuisance rather than catastrophic, and likely lost in the random noise of natural variations.
4. However, I do not believe the earth's climate is dominated by strong positive feedbacks and tipping points.  It is this feedback hypothesis in climate models that multiplies warming to 3-4-5 degrees or more over the next century.  In climate models, the catastrophe comes from feedback, not greenhouse effects, and I think this is a bad hypothesis.  Believers in catastrophic warming have an interesting problem reconciling Mann's hockey stick, which points to incredible stability in temperatures, with a hypothesis of very high positive feedback, which should make temperatures skittish and volatile.  I also think that the hypothesis that aerosols are masking substantial amounts of warming is weak, and appears to be more wishful thinking to bail out model builders than solid science (while there is some cooling effect, the area of effect is local and shouldn't have a substantial effect on global averages).
5. I think the surface temperature record as embodied in the GISS analysis is a joke.  I cannot respect scientists who eschew obviously superior satellite measurements for the half-assed surface temperature record just because it doesn't give them the answer they want to here.  The fact that the leader in fighting for surface temeprature measurement over satellites is James Hansen of NASA's Goddard Institute for Space Studies is the ultimate dark irony.  It's like Bill Gates campaiging for increased abacus use in schools.
6. I have built models of complex systems for years.  I have been guilty many times of allowing seamingly reasonable assumptions to compound into meaningless results.  Unfortunately and embarassingly, I have also been guilty of tweaking, plugging, and tuning models to better match history in order to build confidence in their future predictions.  I see all too many of these same behaviors amoung climate modellers. 

Update to My Best Skeptic's Argument

Based on a lot of comment activity to this post, I wanted to add a bit of an update.  It is sometimes hard to summarize without losing important detail, and I think I had that happen here.

Commenters are correct that positive feedback dominated systems can be stable as long as the feedback percentage is less than 100%.  By trying to get too compact in my arguments, I combined a couple of things.  First, there are many catastrophists that argue that climate IS in fact dominated by feedback over 100% -- anyone who talks of "tipping points" is effectively saying this.  The argument about instability making stable processes impossible certainly applies to these folks' logic.  Further, even positive feedback <100% makes a system highly subject to dramatic variations.  But Mann et. al. are already on the record saying that without man, global temperatures are unbelievably stable and move in extremely narrow ranges.   It is hard to imagine this to be true in a climate system dominated by positive feedback, particularly when it is beset all the time with dramatic perturbations, from volcanoes to the Maunder Minimum.

To some extent, climate catastrophists are in a bind.  If historic temperatures show a lot of variance, then a strong argument can be made that a large portion of 20th century warming is natural occilation.  If historic temperatures move only in narrow ranges, they have a very difficult time justifying that the climate is dominated by positive feedbacks of 60-80%.

The point to remember, though, is that irregardless of likelihood, the historical temperature record simply does not support assumptions of feedback much larger than zero.  Yes, time delays and lags make a small difference, but all one has to do is compare current temperatures to CO2 levels 12-15 years ago to account for this lag and one still gets absolutely no empirical support for large positive feedbacks.

Remember this when someone says that greenhouse gas theory is "Settled."  It may or may not be, but the catastrophe does not come directly from greenhouse gasses.  Alone, they cause at most nuisance warming.  The catastrophe comes from substantial positive feedback (it takes 60-80% levels to get climate sensitivities of 3-5C) which is far from settled science.

Even Shorter Version of Climate Video

After finding out about this contest, I wanted to enter.  However, having very little time, I had to work with something I already had on the shelf.  So I chose to edit this 9+ minute video critiquing catastrophic global warming forecasts to create a three minute version (per the contest rules).

I am pretty sure this is not what the folks running the contest really are looking for, but I had fun trying.   So here is my most edited effort yet, Don't Panic -- The Case Against Catastrophic Global Warming Forecasts. 

I had to just assert some things given the time constraints without presenting the evidence (particularly in the aerosol discussion).  The more complete 9 minute version critiquing global warming forecasts is here.   And the big boy, the 50-minute video covering a wide range of climate change topics, is here.

My Best Skeptic's Argument

Crossposted from Coyote Blog

I began with an 85-page book.  I shortened that to a 50-minute film, and then a 9-minute film.  With that experience, I think I can now pull out and summarize in just a few paragraphs why we should not fear catastrophic global warming.  Here goes:

Climate catastrophists often argue that global warming theory is "settled science."  And they are right in one respect:  We have a pretty good understanding of how CO2 can act as a greenhouse gas and cause the earth to warm.  What is well agreed upon, but is not well communicated in the media, is that a doubling of CO2, without other effects that we will discuss in a moment, will heat the earth about 1 degree Celsius (plus or minus a few tenths).  This is not some skeptic's hallucination -- this is straight out of the IPCC third and fourth assessments.  CO2, acting alone, warms the Earth only slowly, and at this rate we would see less than a degree of warming over the next century, more of a nuisance than a catastrophe.

But some scientists do come up with catastrophic warming forecasts.  They do so by assuming that our Earth's climate is dominated by positive feedbacks that multiply the initial warming from CO2 by a factor of three, four, five or more.  This is a key point -- the catastrophe does not come from the science of greenhouse gases, but from separate hypotheses that the earth's climate is dominated by positive feedback.  This is why saying that greenhouse gas theory is "settled" is irrelevant to the argument about catastrophic forecasts.  Because these positive feedbacks are NOT settled science.  In fact, the IPCC admits it does not even know the sign of the most important effect (water vapor), much less its magnitude.  They assume that the net effect is positive, but they are on very shaky ground doing so, particularly since having long-term stable systems like climate dominated by positive feedback is a highly improbable.

And, in fact, with the 100 or so years of measurements we have for temperature and CO2, empirical evidence does not support these high positive feedbacks.  Even if we assign all the 20th century warming to CO2, which is unlikely, our current warming rates imply close to zero feedback.  If there are other causes for measured 20th century warming other than CO2, thereby reducing the warming we blame on CO2, then the last century's experience implies negative rather than positive feedback in the system.  As a result, it should not be surprising that high feedback-driven forecasts from the 1990 IPCC reports have proven to be way too high vs. actual experience (something the IPCC has since admitted).

However, climate scientists are unwilling to back down from the thin branch they have crawled out on.  Rather than reduce their feedback assumptions to non-catastrophic levels, they currently hypothesize a second man-made cooling effect that is masking all this feedback-driven warming.  They claim now that man-made sulfate aerosols and black carbon are cooling the earth, and when some day these pollutants are reduced, we will see huge catch-up warming.  If anything, this cooling effect is even less understood than feedback.  What we do know is that, unlike CO2, the effects of these aerosols are short-lived and therefore localized, making it unlikely they are providing sufficient masking to make catastrophic forecasts viable.  I go into several reality checks in my videos, but here is a quick one:  Nearly all the man-made cooling aerosols are in the northern hemisphere, meaning that most all the cooling effect should be there -- but the northern hemisphere has actually exhibited most of the world's warming over the past 30 years, while the south has hardly warmed at all.

In sum, to believe catastrophic warming forecasts, one has to believe both of the following:

1. The climate is dominated by strong positive feedback, despite our experience with other stable systems that says this is unlikely and despite our measurements over the last 100 years that have seen no such feedback levels.
2. Substantial warming, of 1C or more, is being masked by aerosols, despite the fact that aerosols really only have strong presence over 5-10% of the globe and despite the fact that the cooler part of the world has been the one without the aerosols.

Here's what this means:  Man will cause, at most, about a degree of warming over the next century.  Most of this warming will be concentrated in raising minimum temperatures at night rather than maximum daytime temperatures  (this is why, despite some measured average warming, the US has not seen an increase of late in maximum temperature records set).  There are many reasons to believe that man's actual effect will be less than 1 degree, and that whatever effect we do have will be lost in the natural cyclical variations the climate experiences, but we are only just now starting to understand.

To keep this relatively short, I have left out all the numbers and such.  To see the graphs and numbers and sources, check out my new climate video, or my longer original video, or download my book for free.

Update:  Commenters are correct that positive feedback dominated systems can be stable as long as the feedback percentage is less than 100%.  By trying to get too compact in my arguments, I combined a couple of things.  First, there are many catastrophists that argue that climate IS in fact dominated by feedback over 100% -- anyone who talks of "tipping points" is effectively saying this.  The argument about instability making stable processes impossible certainly applies to these folks' logic.  Further, even positive feedback <100% makes a system highly subject to dramatic variations.  But Mann et. al. are already on the record saying that without man, global temperatures are unbelievably stable and move in extremely narrow ranges.   It is hard to imagine this to be true in a climate system dominated by positive feedback, particularly when it is beset all the time with dramatic perturbations, from volcanoes to the Maunder Minimum.

To some extent, climate catastrophists are in a bind.  If historic temperatures show a lot of variance, then a strong argument can be made that a large portion of 20th century warming is natural occilation.  If historic temperatures move only in narrow ranges, they have a very difficult time justifying that the climate is dominated by positive feedbacks of 60-80%,

The point to remember, though, is that irregardless of likelihood, the historical temperature record simply does not support assumptions of feedback much larger than zero.  Yes, time delays and lags make a small difference, but all one has to do is compare current temperatures to CO2 levels 12-15 years ago to account for this lag and one still gets absolutely no empirical support for large positive feedbacks.

Remember this when someone says that greenhouse gas theory is "Settled."  It may or may not be, but the catastrophe does not come directly from greenhouse gasses.  Alone, they cause at most nuisance warming.  The catastrophe comes from substantial positive feedback (it takes 60-80% levels to get climate sensitivities of 3-5C) which is far from settled science.

All the "Catastrophe" Comes from Feedback

I had an epiphany the other day:  While skeptics and catastrophists debate the impact of CO2 on future temperatures, to a large extent we are arguing about the wrong thing.  Nearly everyone on both sides of the debate agree that, absent of feedback, the effect of a doubling of CO2 from pre-industrial concentrations (e.g. 280 ppm to 560 ppm, where we are at about 385ppm today) is to warm the Earth by about 1°C ± 0.2°C.  What we really should be arguing about is feedback.

In the IPCC Third Assessment, which is as good as any proxy for the consensus catasrophist position, it is stated:

If the amount of carbon dioxide were doubled instantaneously, with everything else remaining the same, the outgoing infrared radiation would be reduced by about 4 Wm-2. In other words, the radiative forcing corresponding to a doubling of the CO2 concentration would be 4 Wm-2. To counteract this imbalance, the temperature of the surface-troposphere system would have to increase by 1.2°C (with an accuracy of ±10%), in the absence of other changes.

Skeptics would argue that the 1.2°C is (predictably) at the high end of the band, but in the ballpark none-the-less.  The IPCC also points out that there is a diminishing return relationship between CO2 and temperature, such that each increment of CO2 has less effect on temperature than the last.  Skeptics also agree to this.  What this means in practice is that though the world, currently at 385ppm CO2, is only about 38% of the way to a doubling of CO2 from pre-industrial times, we should have seen about half of the temperature rise for a doubling, or if the IPCC is correct, about 0.6°C (again absent feedback).  This means that as CO2 concentrations rise from today's 385 to 560 toward the end of this century, we might expect another 0.6°C warming.

This is nothing!  We probably would not have noticed the last 0.6°C if we had not been told it happened, and another 0.6°C would be trivial to manage.  So, without feedback, even by the catastrophist estimates at the IPCC, warming from CO2 over the next century will not rise about nuisance level.  Only massive amounts of positive feedback, as assumed by the IPCC, can turn this 0.6°C into a scary number.  In the IPCC's words:

To counteract this imbalance, the temperature of the surface-troposphere system would have to increase by 1.2°C (with an accuracy of ±10%), in the absence of other changes. In reality, due to feedbacks, the response of the climate system is much more complex. It is believed that the overall effect of the feedbacks amplifies the temperature increase to 1.5 to 4.5°C. A significant part of this uncertainty range arises from our limited knowledge of clouds and their interactions with radiation. …

So, this means that debate about whether CO2 is a greenhouse gas is close to meaningless.  The real debate should be, how much feedback can we expect and in what quantities?  (By the way, have you ever heard the MSM mention the word "feedback" even once?)   And it is here that the scientific "consensus" really breaks down.  There is no good evidence that feedback numbers are as high as those plugged into climate models, or even that they are positive.  This quick analysis demonstrates pretty conclusively that net feedback is probably pretty close to zero.  I won't go much more into feedback here, but suffice it to say that climate scientists are way out on a thin branch in assuming that a long-term stable process like climate is dominated by massive amounts of positive feedback.  I discuss and explain feedback in much more detail here and here.

Update:  Thanks to Steve McIntyre for digging the above quotes out of the Third Assessment Report.  I have read the Fourth report cover to cover and could not find a single simple statement making this breakdown of warming between CO2 in isolation and CO2 with feedbacks.  The numbers and science has not changed, but they seem to want to bury this distinction, probably because the science behind the feedback analysis is so weak.

Incredible Climate Resource

Courtesy of Tom Nelson comes a pointer to this incredible link-rich page of climate articles, mostly from a skeptical perspective.

Podcast of My Interview on Climate Now Available

The podcast audio of Duane Lester's interview of yours truly about climate issues is now up here.  You can decide for yourself if this is true.

Podcast Tonight

I will be on the All American Blogger podcast tonight, live here at 10PM, or of course any time after that through miracle of MP3 here.  Never tried this format before with call-in questions and stuff, so it should be interesting.  I will be discussing climate and catastrophic man-made global warming theory.

Podcast Tonight

I will be on the All American Blogger podcast tonight, live here at 10PM, or of course any time after that through miracle of MP3 here.  Never tried this format before with call-in questions and stuff, so it should be interesting.  I will be discussing climate and catastrophic man-made global warming theory.

Single Best Reason Not to Panic About Climate

When I have only 60 seconds to explain why I dont think man-made global warming will be catastrophic enough to warrant massively expensive CO2 abatement programs, this is my argument:

1. CO2 does indeed absorb selected wavelengths of readiation returning to space from earth, having a warming effect on the atmosphere.  However, this effect is a diminishing return -- each successive increment of CO2 concentrations will have a much smaller effect on temperatures than the previous increment.  Eventually, CO2 becomes nearly saturated in its ability to absorb radiation.  The effect is much like painting a red room with white paint.  The first coat covers a lot of red but some still shows through.  Each additional coat will make the room progressively whiter, but each successive coat will have a less noticeable effects than the previous coat, until the room is just white and can't get any whiter  (the "layers" of CO2 are shown in pink below)

 

2. In the 20th century, the UN IPCC claims Earth's surface temperatures have increased by about a 0.6 degree Celsius (though there are some good reasons to think that biases in the installation of temperature instruments have exaggerated this apparent increase).  To be simple (and generous), let's assume all this 0.6C increase is due to man-made greenhouse gasses.  Some may in fact have been due to natural effects, but some may also have been masked by man-made sulfate aerosols, so lets just call man-made warming to be 0.6C. 


3. Since the beginning of the industrial revolution, it is thought that man has increased atmospheric CO2 concentrations from 0.028% of the atmosphere to 0.038% of the atmosphere.  Since scientists often talk about the effect of a doubling of CO2, this historic rise in CO2 is 36% of a doubling.


4. Using simple math, we see that if temperatures have risen 0.6C due to 36% of a doubling, we might expect them to rise by 1.67C for a full doubling to 0.056% of the atmosphere.  But this assumes that the rise is linear -- and we already said (and no one denies) that it is in fact a diminishing return relationship.  Using a truer form of the curve, a 0.6C historic rise for 36% of a doubling implies a full doubling would raise temperatures by about 1.2C, or about 0.6C more than we have seen to date (see chart below).   This means that the magnitude of global warming in the next century might be about what we have seen (and apparently survived) since 1900.





5. Obviously, there is some kind of disconnect here.  The IPCC predicts temperature increases in the next century of 4-8 degrees C.  Big difference.  In fact, the IPCC predicts we will get a 0.5C rise in just 20 years, not 70-100.  Whereas we derived a climate sensitivity of 1.2 from empirical data, they arrive at numbers between 3 and 4 or even higher for sensitivity.  The chart below shows that to believe sensitivity is 3, we would have to have seen temperature rises due to man historically of 1.5C, which nobody believes. 

   

   So how do they get accelerating temperatures from what they admit to be a diminishing return relation between CO2 concentration and temperature? And for which there is no empirical evidence?  Answer:  Positive feedback.

6. Almost every process you can think of in nature operates by negative feedback.  Roll a ball, and eventually friction and wind resistance bring it to a stop.  Negative feedback is a ball in the bottom of a bowl; positive feedback is a ball perched precariously at the time of a mountain. Positive feedback breeds instability, and processes that operate by positive feedback are dangerous, and usually end up in extreme states -- these processes tend to "run away" like the ball rolling down the hill.  Nuclear fission, for example, is a positive feedback process.  We should be happy there are not more positive feedback processes on our planet.  Current man-made global warming theory, however, asserts that our climate is dominated by positive feedback.  The IPCC posits that a small increase in temperature from CO2 is multiplied 2,3,4 times or more by positive feedbacks like humidity and ice albedo.


7. There are three problems with these assumptions about positive feedback.  One, there is no empirical evidence at all that positive feedbacks in climate dominate negative feedbacks.   The 20th century temperature numbers we discussed above show no evidence of these feedbacks.  Since we used empirical numbers to calculate the sensitivity, it is already net of any feedbacks. Two, the long-term temperature record demonstrates that positive feedbacks can't dominate, because past increases in temperature and CO2 have not run away.  And three, characterizations of stable natural processes as being dominated by positive feedback should offend the intuition and common sense of any scientist.


8. An expected 21st century increase of 0.5 or even 1 degree C does not justify the massive imposed government interventions that will be costly both in dollars and lost freedoms.  In particular, the developing world will be far better off hotter by a degree and richer than it would be cooler and poorer.  This is particularly true since sources like an Inconvenient Truth wildly exaggerate the negative effects of global warming.  There is no evidence tornadoes or hurricanes or disease or extinction are increasing as the world warms, and man-made warming advocates generally ignore any potential positive effects of warming.  As to rising sea levels, the IPCC predicts only a foot and a half of sea level rise even with 4 or more degrees of warming.  Sea level rise from a half to one degree of warming would be measured at most in inches.

OK, so that was more than 60 seconds.  But it is a lot less than 80 pages.  There is a lot of complexity behind every one of these statements.  If you are intrigued, or at least before you accuse me of missing something critical, see my longer paper on global warming skepticism first, where all these issues and much more (yes, including tree rings and cosmic rays) are discussed in more depth.  You can also watch my free climate movie.

More Ways to View My Climate Video

There has been a lot of interest in my new climate video.  Already we have nearly 450 1400 views at Google video and over 200 800 downloads of the video.  I am now releasing the video on DVD and through YouTube.

I have had several requests for a DVD version rather than an online version or file.  For a limited time, through December 31, 2007, I will send a DVD of my video What is Normal?  A Critique of Catastrophic Man-Made Global Warming Theory to anyone who sends me a stamped self-addressed envelope.  The DVD plus a standard CD mailer weigh about 3.3 OZ, so you will need $1.31 postage in the US.  Send your request to "Climate Video, c/o Warren Meyer, 11811 N. Tatum Blvd #4095, Phoenix, AZ, 85253"

Also, in response to popular demand, I have release the video on YouTube.  YouTube requires that all videos be under 10 minutes, so I have broken the film into six parts.  If you want to just preview a portion, the second half of the fourth film and the first half of the fifth are probably the most critical.

A Youtube Playlist for the film is here.  This is a cool feature I have not used before, but will effectively let you run the parts end to end, making the 50-minute video more or less seamless. 

The individual parts are:

Climate Video Part 1:  Introduction; how greenhouse gases work; historical climate reconstructions
Climate Video Part 2:  Historical reconstructions; problems with proxies
Climate Video part 3:  How much warming is due to man; measurement biases; natural cycles in climate
Climate Video Part 4:  Role of the sun; aerosols and cooling; climate sensitivity; checking forecasts against history
Climate Video Part 5:  Positive and negative feedback;  hurricanes.
Climate Video Part 6:  Melting ice and rising oceans; costs of CO2 abatement; conclusions.

You may still stream the entire climate film from Google Video here. (the video will stutter between the 12 and 17 second marks, and then should run fine)

You may download a 258MB full resolution Windows Media version of the film by right-clicking here.

You may download a 144MB full resolution Quicktime version of the film by right-clicking here.

Climate Video Release!

My first climate movie, What is Normal?  A Critique of Catastrophic Man-Made Global Warming Theory is now available for free download.  If you have the bandwidth, I encourage you to download the full 640x480 version as Windows Media Video, but be forewarned that the file is 258MB.  This is actually a pretty small file for a 50+ minute movie, and the full resolution version looks much nicer than the streaming version.

Right-Click Here to Download Climate Movie in Full Resolution

Update:  Right-Click here for full resolution 144MB .mov quicktime version of Climate Movie

Make sure you turn up your volume -- I think I recorded this with a pretty low audio level.

If you are bandwidth-challenged, or you can't view a .WMV file, you may stream the video from Google video or download a reduced resolution version here.  Unfortunately, to make the video stream effectively, the resolution is cut to 320x240, but having watched it, it actually still looks surprisingly good streamed. 

Note, on the streaming version, the video stutters between the 12 and 17 second marks in the movie, but runs fine after that.  By the way, thanks to all the commenters who gave me some good alternatives to using my own fairly week narration voice.  I decided for this first release I wanted to see what I could achieve with a pure solo effort.  Many thanks to Adobe Premier Elements, which made this effort possible.

Finally, you can stream the reduced resolution Google video version below:

New Global Warming Video Release

Please check back Monday morning, as I will be releasing my new video, "What is Normal:  A Critique of Catastrophic Man-Made Global Warming Theory."  As with my global warming book, which began as a ten page summary and ended up as an 85-page manuscript, the video started at a goal of 15 minutes and eventually ended up at 50 minutes.  However, unlike other global warming-related videos I will not name, it is all climate science, with no self-congratulatory segments on my childhood.

Duh

From Megan McArdle:

Matt may be right that I haven't harangued people about climate change recently, so here goes: dude, if you're still a climate change skeptic, it's time for a rethink. When the science correspondent for Reason magazine comes over to the reality of anthropogenic global warming, it's safe to say that the skeptics have lost the debate. Not only the vast majority of the scientific community, but even most of the hard-core skeptics at conservative magazines, have abandonned the hope that we are not warming up the climate.

There's still debate about the effects of the warming, and what we should do about it. But there's not much question that it's happening.

Duh.  The vision of the skeptic community denying that the world is warming at all is a straw man created by the climate catastrophists to avoid arguing about the much more important point in her second paragraph.  What I can't understand is McArdle's, and many intelligent people I meet, seeming unintrest in the degree of man-made impact.

The chief debate really boils down to those of us who think that climate sensitivity to CO2 is closer to 1C (ie the degrees the world will warm with a doubling of CO2 concentrations from pre-industrial levels) and those who think that the sensitivity is 3-5C or more.  The lower sensitivity implies a warming over the next century of about a half degree C, or about what we saw in the last century.  The higher numbers represesent an order of magnitude more warming in the next century.  The lower numbers imply a sea level rise measured in inches.  The higher numbers imply a rise of 1-2 feet  (No one really know where Al Gore gets his 20 foot prediction in his movie).  The lower numbers we might not even notice.  The higher numbers will certainly cause problems.

The other debate is whether the cost of CO2 abatement should even be considered.  I have talked to many people who say the costs are irrelevent - Gaia must come first.  But steps to make any kind of dent in CO2 production with current technologies will have a staggering impact on the world economy.  For example, there are a billion Asians poised to finally to enter the middle class who we will likely consign back to poverty with an aggresive CO2 reduction program.  With such staggering abatement costs, it matters how bad the effects of man-made global warming will be. 

There are many reasons a 1.0 climate sensivity is far more defensible than the higher sensitivities used by catastrophists.  My argument a lower climate sensitivity and therefore a less aggresive posture on CO2 is here.  Cross-posted at Coyote Blog.

Update: Sure, we skeptics debate the degree of past warming, but it really can't be denied the earth is warmer than 100 years ago.  The problem catastrophists have with defending their higher climate sensitivities is that these sensitivities imply that we should have seen much more warming over the past 100 years, as much as 1.5C or more instead of about 0.6C.  These scientists have a tendency to try to restate historical numbers to back their future forecast accuracy.  We skeptics fight them on this, but it does not mean we are trying to deny warming at all, just make sure the science is good as to the magnitude.

One other thought - everyone should keep two words in mind vis a vis CO2 and its effect on temperature:  Diminishing Return.  Each new molecule of CO2 has less impact on temperature than the last one.  Only by positing a lot of weird, unlikely, and unstable positive feedbacks in the climate can scientists reach these higher sensitivity numbers (more here).  A good economist would laugh if they understood the assumptions that were being made in the catastrophic forecasts that are being used to influence government action.

Pretty Good Skeptic's Video

Raises many good issues, but with little depth. If you want more, get the free download of my book at the right or look for my own video, coming soon.

Why I Don't Fear Catastrophic Warming (in Two Graphs)

Scientists have a concept called climate sensitivity which refers to the amount of global warming in degrees Celsius we might expect from a doubling of CO2 concentrations from a pre-industrial 280ppm to 560ppm  (we are currently at about 380ppm today and will reach 560ppm between 2065 and 2100, depending on how aggressive a forecast you want to adopt).

A simple way to estimate sensitivity is from experience over the past century.  At the same time CO2 has gone up by 100ppm, global temperatures have gone up by at most 0.6 Celsius (from the 4th IPCC report).  I actually believe this number is over-stated due to uncorrected urban effects and other surface temperature measurement issues, but let's assume 0.6ºC.  Only a part of that 0.6ºC is due to man - some is likely do to natural cyclical effects, but again to avoid argument, let's assume man's CO2 has heated the earth 0.6 Celsius.  From these data points, we can project forward:

As you can see, the projection is actually a diminishing curve.  For reasons I will not go into again (you can read much more in this post) this relationship HAS to be a diminishing curve.  It's a fact accepted by everyone.  True climate consensus.  We can argue about the slope and exact shape, but I have chosen midpoint values from a reasonable range.  The answer is not that sensitive to different assumptions anyway.  Even a linear extrapolation, which is clearly wrong scientifically, would only yield a sensitivity projection a few tenths of a degree higher.

What we arrive at is a sensitivity of about 1.2 degrees Celsius for a CO2 doubling (where the blue line crosses 560ppm).  In other words, we can expect another 0.6ºC increase over the next century, about the same amount we experienced (and most of us failed to notice) over the last century.

But, you are saying, global warming catastrophists get so much higher numbers.  Yes they do, with warming as high as 9-10C in the next century.  In fact, most global warming catastrophists believe the climate sensitivity is at least 3ºC per doubling, and many use estimates as high as 5ºC or 6ºC.  Do these numbers make sense?  Well, let's draw the same curve for a sensitivity of 3ºC, the low end of the catastrophists' estimates, this time in red:

To get a sensitivity of 3.0ºC, one has to assume that global warming due solely to man's CO2 (nothing else) would have to be 1.5ºC to date (where the red line intersects the current concentration of 380ppm).  But no one, not the IPCC or anyone else, believes measured past warming has been anywhere near this high.  So to believe the catastrophic man-made global warming case, you have to accept a sensitivity three or more times higher than historical empirical data would support.  Rather than fighting against climate consensus, which is how we are so often portrayed, skeptics in fact have history and empirical data on our side.  For me, this second chart is the smoking gun of climate skepticism.  We have a lot of other issues -- measurement biases, problems with historical reconstructions, role of the sun, etc -- but this chart highlights the central problem -- that catastrophic warming forecasts make no sense based on the last 100+ years of actual data.

Global warming catastrophists in fact have to argue against historical data, and say it is flawed in two ways:  First, they argue there are positive feedbacks in climate that will take hold in the future and accelerate warming; and second, they argue there are other anthropogenic effects, specifically sulphate aerosols, that are masking man-made warming.  Rather than just repeat myself (and in the interest in proving I can actually be succinct) I will point you to this post, the second half of which deals in depth with these two issues. 

As always, you can find my Layman's Guide to Skepticism about Man-made Global Warming here.  It is available for free in HTML or pdf download, or you can order the printed book that I sell at cost.

Table of Contents: A Layman's Guide to Man-Made Global Warming

The purpose of this paper is to provide a layman’s critique of the Anthropogenic Global Warming (AGW) theory, and in particular to challenge the fairly widespread notion that the science and projected consequences of AGW currently justify massive spending and government intervention into the world’s economies.  This paper will show that despite good evidence that global temperatures are rising and that CO2 can act as a greenhouse gas and help to warm the Earth, we are a long way from attributing all or much of current warming to man-made CO2.  We are even further away from being able to accurately project man’s impact on future climate, and it is a very debatable question whether interventions today to reduce CO2 emissions will substantially improve the world 50 or 100 years from now.

Update:  If you would like to start with the 60-second version of this long paper, try here first. 

Update #2:  NEW! A streaming video version of this guide is also available -- see below, or you can find the long version here or the shorter version here.

Note you may click on any of the chapter links below to see the full chapter in HTML, or see below for links to free pdf versions available for download.

Table of Contents for A Layman's Guide to Anthropogenic Global Warming (AGW)
Chapter 1: Summary of Global Warming Skeptics Position
Chapter 2:  Is It OK to be a Global Warming Skeptic? 

• Charges of Bias
• The Climate Trojan Horse
• The Need to Exaggerate

Chapter 3: The Basics of Anthropogenic Global Warming (AGW) Theory
Chapter 4:  The Historical Evidence for Man-Made Global Warming

• The long view (650,000 years)
• The medium view (1000 years)
• The short view (100 years)
• Sulfates, Aerosols and Dimming
• The troposphere and Urban heat islands
• Using Computer Models to Explain the Past

Chapter 5:  The Climate Computer Models and Predicting Future Temperatures

• The Dangers in Modeling Complex Systems
• Do Model Outputs Constitute Scientific Proof?
• Econometrics and CO2 Forecasts
• Climate Sensitivity and the Role of Positive Feedbacks
• Climate Models have to be Aggressively Tweaked to Match History 

Chapter 6:  Alternate Explanations and Models for Global Warming

• Solar Irradiance
• Cosmic Rays
• Man's Land Use 

Chapter 7:  The Effects of Global Warming

• Why only bad stuff?
• Ice melting / Oceans Rising
• Hurricanes & Tornadoes
• Temperature Extremes
• Extinction and Disease
• Collapse of the Gulf Stream and Freezing of Europe
• Non-warming Effects of CO2

Chapter 8:  Kyoto and Climate Change Policy Alternatives

• Kyoto
• Cost of the Solutions vs. the Benefits:  Why Warmer but Richer may be Better than Colder and Pooer

Chapter 9: Rebuttals by Man-Made Global Warming Theory Supporters

UPDATE:  A video version of this guide called What is Normal?  A Critique of Catastrophic Man-Made Global Warming Theory is now available for free download. 

A Youtube Playlist for the film is here.  This is a cool feature I have not used before, but will effectively let you run the parts end to end, making the 50-minute video more or less seamless. 

The individual parts are:

Climate Video Part 1:  Introduction; how greenhouse gases work; historical climate reconstructions
Climate Video Part 2:  Historical reconstructions; problems with proxies
Climate Video part 3:  How much warming is due to man; measurement biases; natural cycles in climate
Climate Video Part 4:  Role of the sun; aerosols and cooling; climate sensitivity; checking forecasts against history
Climate Video Part 5:  Positive and negative feedback;  hurricanes.
Climate Video Part 6:  Melting ice and rising oceans; costs of CO2 abatement; conclusions.

You may also stream the entire climate film from Google Video here. (the video will stutter between the 12 and 17 second marks, and then should run fine)

You may download a 258MB full resolution Windows Media version of the film by right-clicking here.

You may download a 144MB full resolution Quicktime version of the film by right-clicking here.

A 9-minute version of the climate video can be found here.

For those interested in getting a copy of my A Skeptical Layman's Guide to Anthropogenic Global Warming, I greatly encourage you to download it for free.  However, I do know that some folks have written about a print version.  I have a print version of my global warming book available now at LuLu.com. It is $16.98 -- that is my cost -- and I warn you that LuLu's shipping options are not very cheap.  I will try to find a less expensive print option, but no one beats LuLu for getting a book set up quickly and easily for print-to-order.

The open comment thread for this paper can be found here.

Chapter 1: Summary of the Skeptical Layman's Guide to Man-Made Global Warming

The table of contents for the rest of this paper, A Layman's Guide to Anthropogenic Global Warming (AGW) is here.  Free pdf of this Climate Skepticism paper is here and print version is sold at cost here.

We know the temperature of the Earth has increased over the last half of the 19^th century and most of the 20^th century as the world has exited a particularly cold period called the Little Ice Age.  One of the odd coincidences that colors our judgment about climate trends is that man began systematically measuring temperatures in the early to mid-nineteenth century just as the world was beginning to exit what was perhaps the coldest period of the last millennia.  Throughout their study of climate trends, scientists have to try to parse warming that is a natural result of exiting this cyclical cold period from warming that is perhaps due to man’s influence.

We know further, from laboratory work, that CO2, and more importantly water vapor, in the atmosphere serves to keep the Earth warmer than it would be in their absence.  What we don’t know, in fact what we have no empirical proof for, is if rising CO2 levels over the last century (caused in part by man’s combustion of fossil fuels) has caused some or all of the 20^th century warming.  The fact that we have no empirical evidence for this man-made effect on climate doesn’t mean it is not true, but it is something we should not forget in all this debate.  What we have instead are historical correlations in the data, far from perfect, that seem to show some relationship over history between CO2 and temperature.  Some find this data to be compelling evidence of cause and effect, and others do not. 

Before we start, since this paper is by definition somewhat in opposition to the core of Anthropogenic Global Warming (AGW) theory, it would be useful to state in simple terms just what that theory is.   The strong AGW hypothesis is roughly as follows:

1. The world has been warming for a century, and this warming is beyond any cyclical variation we have seen over the last 1000 or more years, and beyond the range of what we might expect from natural climate variations.

2. Almost all of the warming in the second half of the 20^th century, perhaps a half a degree Celsius, is due to man-made greenhouse gasses, particularly CO2

3. In the next 100 years, CO2 produced by man will cause a lot more warming, from as low as three degrees C to as high as 8 or 10 degrees C.

4. Positive feedbacks in the climate, like increased humidity, will act to triple the warming from CO2, leading to these higher forecasts and perhaps even a tipping point into climactic disaster

5. The bad effects of warming greatly outweigh the positive effects, and we are already seeing the front end of these bad effects today (polar bears dying, glaciers melting, etc)

6. These bad effects, or even a small risk of them, easily justify massive intervention today in reducing economic activity and greenhouse gas production

In the rest of this paper, we will focus on potential weaknesses in this hypothesis. Specifically, I will argue that:

There is no doubt that CO2 is a greenhouse gas, and it is pretty clear that CO2 produced by man has an incremental impact on warming the Earth’s surface. 

However, recent warming is the result of many natural and man-made factors, and it is extraordinarily difficult to assign all the blame for current warming to man. 

In turn, there are very good reasons to suspect that climate modelers may be greatly exaggerating future warming due to man.  Poor economic forecasting, faulty assumptions about past and current conditions, and a belief that climate is driven by runaway positive feedback effects all contribute to this exaggeration. 

As a result, warming due to man’s impacts over the next 100 years may well be closer to one degree C than the forecasted six to eight.  In either case, since AGW supporters tend to grossly underestimate the cost of CO2 abatement, particularly in lost wealth creation in poorer nations, there are good arguments that a warmer but richer world, where aggressive CO2 abatement is not pursued, may be the better end state than a poor but cooler world.

In Chapter 2, we will address whether it is even appropriate to be a skeptic.  Of late, several AGW supporters have declared the science “settled,” and skeptics the equivalent of tobacco lawyers or holocaust deniers.  We will also look at the issue of bias, not just for skeptics but for AGW supporters as well.

In Chapter 3, we will cover a bit of background on Anthropogenic Global Warming (AGW) theory.  We  will learn some things about the CO2 greenhouse effect you have probably never heard in the media, such as the fact that warming from CO2 is actually a diminishing return phenomenon whose effect is asymptotic or essentially capped, making it hard to understand the prevalence of wild, open-ended temperature runaway scenarios.

In Chapter 4, we will review the historic empirical evidence for AGW theory.  We will find that the science of historic climate reconstruction is still in its infancy, and a lot of uncertainty exists in the data.  We will see that over the last several years, while correlations between CO2 and temperature exist in the data, much of the historical circumstantial evidence for AGW theory has gotten weaker, and we will cover “global dimming” and see if this effect makes the case for AGW stronger.

In Chapter 5 we will cover the absolutely fascinating topic of climate models.  Most of what you have seen in the media is the output of complex climate models.  We will find that there is a lot less here than meets the eye.

In Chapter 6 we will study several alternate explanations for recent warming that don’t involve man-made greenhouse gasses.  Most prominent in these theories is the changing output of the sun.

In Chapter 7 we take on the scare stories – the lions and tigers and bears of climate reporting.  In the movie An Inconvenient Truth, Al Gore caught the world’s attention with prophecies of seas rising twenty feet, hurricanes and tornados running rampant, and species dying. We will find that most of these claims are thought to be wild exaggerations even by scientists who support AGW theory.

In Chapter 8 we finally get to the Kyoto Treaty, explain its origins and shortcomings, and briefly discuss some policy alternatives. We’ll seriously consider whether a cooler but poorer world is really superior to a warmer but richer world.

Finally, in Chapter 9, we will consider AGW supporter’s rebuttals of some of these arguments.  For this version, we will use the New Scientist’s recent 26 Global Warming Myths as a platform for this discussion.

My Goals For This Paper

The purpose of this paper is to provide a layman’s critique of the Anthropogenic Global Warming (AGW) theory, and in particular to challenge the fairly widespread notion that the science and projected consequences of AGW currently justify massive spending and government intervention into the world’s economies.  This paper will show that despite good evidence that global temperatures are rising and that CO2 can act as a greenhouse gas and help to warm the Earth, we are a long way from attributing all or much of current warming to man-made CO2.  We are even further away from being able to accurately project man’s impact on future climate, and it is a very debatable question whether interventions today to reduce CO2 emissions will substantially improve the world 50 or 100 years from now.

I am not a trained expert on the climate.  I studied physics at Princeton University before switching my major to mechanical engineering, where I specialized in control theory and feedback loops, a topic that will be important when we get into the details of climate change modeling.  For over ten years, my business specialty was market prediction and sales forecasting using modeling approaches similar to (if far less complex than) those used in climate.

My goal for this paper is not to materially advance climate science.  However, I have found that the global warming skeptic’s case is seldom reported well or in any depth, and I wanted to have a try at producing a fair reporting of the skeptic’s position.   I have been unhappy with several of the recent documentaries outlining the skeptic’s case, either because they skipped over a number of critical issues, or because they over-sold alternate warming hypotheses that are not yet well understood. To the inevitable charge that as a non-practitioner, I am not qualified to write this paper --I believe that I am able to present the current state of the science, with a particular emphasis on the skeptic’s case, at least as well as a good reporter might, and far better than most reporters actually portray the state of the science.  Through this paper I will try to cite sources as often as possible and provide links for those who are reading this online, this report is best read as journalism, not as a scientific, meticulously footnoted paper.

Years ago, another man not trained in climate started a PowerPoint presentation of what he knew about Global Warming.  Over time, he used it both as a vehicle for communication as well as a living document that would evolve over time to reflect his improving knowledge.  A lot of people saw Al Gore’s PowerPoint presentation, and it became the backbone for the movie An Inconvenient Truth.  I hope to use this paper the same way, as an evolving document to reflect my evolving knowledge.  To this end, each version will get a software-like version number and date.

Before proceeding, I want to make one note on nomenclature.  The terms global warming and climate change are often used interchangeably, and generally are used in a way that imply man-made causes.  For example, when many people speak of global warming, they are actually talking about anthropogenic global warming, meaning warming of the Earth from man-made causes, generally the release of greenhouse gasses including CO2.  Of course the climate can, and does, change without man’s help and the Earth can warm without man-made gasses.  I will try to be precise in my terminology.  I will use global warming to mean literally an increase in Earth’s surface temperatures, no matter what the cause.  I will use anthropogenic global warming, or AGW, to mean the theory that man is causing some or all of the current warming.

Finally, any abuse of copyrighted material or mistakes in attribution are entirely unintentional.  Such problems, as well as any comments, should be sent to the author at the email address on the cover.

The table of contents for the rest of this paper, A Layman's Guide to Anthropogenic Global Warming (AGW) is here.  Free pdf of this Climate Skepticism paper is here and print version is sold at cost here.

The open comment thread for this paper can be found here. 

Chapter 2 (Skeptics Guide to Global Warming): Is it OK to be a Skeptic?

The table of contents for the rest of this paper, A Layman's Guide to Anthropogenic Global Warming (AGW) is here.  Free pdf of this Climate Skepticism paper is here and print version is sold at cost here.

For the first time since the Catholic Church dominated western man’s affairs, it has suddenly become a sin again to be labeled a “skeptic.”  For most of my lifetime, “skepticism” was considered an essential element in the makeup of any good scientist (or journalist, for that matter).   However, leading world figures are declaring skepticism to be immoral.  Take one example, from this UPI story:

A former chief of the U.N. World Health Organization who also is a former prime minister of Norway and a medical doctor has declared an end to the climate-change debate.

Dr. Gro Harlem Brundtland, one of U.N. Secretary-General Ban Ki-moon's three new special envoys on climate change, also headed up the 1987 U.N. World Commission on Environment and Development where the concept of sustainable development was first floated.

"This discussion is behind us. It's over," she told reporters. "The diagnosis is clear, the science is unequivocal -- it's completely immoral, even, to question now, on the basis of what we know, the reports that are out, to question the issue and to question whether we need to move forward at a much stronger pace as humankind to address the issues."

In its most extreme form, this approach has AGW supporters labeling skeptics as equivalent to “holocaust deniers” and “tobacco lawyers.”  Efforts have been made in several quarters to decertify climatologists or meteorologists who show any skepticism for AGW theory, making public adherence to the theory a minimum qualification for publication and professional standing.  Enormous efforts are made to squelch skeptical speech.  Just as one example, the BBC has run a zillion shows and specials sympathetic to AGW.  When Channel 4 ran one single show (called the “Global Warming Swindle”) which outlined parts of the skeptics’ position, 37 scientists attempted to have it suppressed by the government.

This is all the more incredible given that AGW theory has only really been researched seriously and with any critical mass for about 20 years.  Anyone who has studied the history of science will understand what incredible hubris it is to declare any new scientific theory, particularly one that concerns the unbelievably chaotic climate, as “done” after just 20 years work. 

Let me give two quick examples of just how unsettled the science of climate change is.  Both of these will be reviewed in more depth later in this paper, and both analyses figured prominently in the third IPCC report (2001) as well as Al Gore’s An Inconvenient Truth.  The first is a 100,000 year temperature and CO2-level reconstruction from ice-core data.  Anyone who saw Gore’s movie will remember the data in one of his Really Big Charts.  And it looks compelling – in fact, when I first saw the chart five years ago, it was compelling to me.  It shows CO2 levels and temperature moving in lock-step for 100,000 years.  When CO2 is up, temperature is up and vice-versa, the clear implication being that CO2 seems to be a key, maybe the key, driver of climate   However, since that chart was first prepared, laboratory procedure has improved, and scientists have found (and there is very little disagreement about this, even among strong AGW supporters) that temperature increases occur on average 800 years before the CO2 starts to increase.  Huh.  There is a lot of debate about what this means, but in the last five years, this formerly definitive analysis is clearly no longer definitive, since it is hard to cause something after the fact.

The other example is the very famous Mann hockey stick chart, prominently featured in Gore’s movie and a key part of the IPCC report in 2001.  I will go into the details later, but since 2001 this analysis has been effectively discredited, so much so it was almost entirely missing from the fourth IPCC report in 2007.  In 2003 or so, Al Gore and many AGW supporters would have called the Mann hockey stick chart the single most important analysis “proving” AGW, and Gore treated it as such in his PowerPoint deck and his movie.  Then, in 2007, it is repudiated and expunged from the record.  Is this really what any reasonable person would call a “settled” science?

It is a true perversion of the scientific process to find that skepticism is no longer welcome or accepted in scientific debate. Which is one reason that AGW is sometimes called a secular religion. Because it is religion, not science, that burns skeptics at the stake.  Climate Scientists Garth Paltridge wrote:

A colleague of mine put it rather well. The IPCC, he said, has developed a highly successful immune system. Its climate scientists have become the equivalent of white blood cells which rush in overwhelming numbers to repel infection by ideas and results which do not support the basic thesis that global warming is perhaps the greatest of the modern threats to mankind.

Charges of Bias

A funny thing has happened in climate science to scientific inquiry: the usual ethics of free discussion and fact-based criticism have been discarded in favor of ad hominem attacks on critics of AGW theory. The usual approach is to find some connection (even an imagined one) between any researcher who raises the smallest doubts about AGW theory and an oil or power company and then declare that the research is tainted by the bias of these companies that have a strong economic reliance on fossil fuel combustion (and thus the production of CO2).  A good example can be found in a Boston Globe article on MIT's Alfred P. Sloan professor of meteorology Richard Lindzen.  Mr. Lindzen has become the bete noir of AGW supporters, since his skepticism is harder to dismiss given his scientific pedigree and his co-lead author status on the first IPCC climate change report.

"We do not understand the natural internal variability of climate change" is one of Lindzen's many heresies, along with such zingers as `"the Arctic was as warm or warmer in 1940," "the evidence so far suggests that the Greenland ice sheet is actually growing on average," and "Alpine glaciers have been retreating since the early 19th century, and were advancing for several centuries before that. Since about 1970, many of the glaciers have stopped retreating and some are now advancing again. And, frankly, we don't know why."

When Lindzen published similar views in The Wall Street Journal this spring, environmentalist Laurie David, the wife of comedian Larry David, immediately branded him a "shill." She resurrected a shopworn slur first directed against Lindzen by former Globe writer Ross Gelbspan, who called Lindzen a "hood ornament" for the fossil fuels industry in a 1995 article in Harper's Magazine....

For no apparent reason, the state of California, Environmental Defense, and the Natural Resources Defense Council have dragged Lindzen and about 15 other global- warming skeptics into a lawsuit over auto- emissions standards. California et al. have asked the auto companies to cough up any and all communications they have had with Lindzen and his colleagues, whose research has been cited in court documents.

"We know that General Motors has been paying for this fake science exactly as the tobacco companies did," says ED attorney Jim Marston. If Marston has a scintilla of evidence that Lindzen has been trafficking in fake science, he should present it to the MIT provost's office. Otherwise, he should shut up.

"This is the criminalization of opposition to global warming," says Lindzen, who adds he has never communicated with the auto companies involved in the lawsuit.

While I have no doubt that corporations are heavily influenced by their own economic interests, it is more of stretch to argue that anyone who has ever taken money from them or had any connection with them would purposely bias their research.  When I learned to debate, I was taught that understanding biases was useful in knowing when to apply more or less skepticism, but one still has to refute the opposing position by meaningful critique of procedures or data.   For example, one might say “given their strong desire to buttress the case for AGW, the researchers cherry-picked only the most extreme data, which I will demonstrate by showing the data they included and the data they chose to exclude.”  However, many modern AGW supporters believe that insinuating possible sources of bias is sufficient to exempt one from having to actually critique their opponents’ methods and findings. 

This is particularly odd given that public funding for AGW projects absolutely dwarfs any funding coming from private sources whose incentive might be to disprove AGW.  In fact, just this year, President Bush declared that the US Government alone spent more money on AGW research than on AIDS research, and the US is actually late in the climate funding game. 

Recently, Greenpeace criticized ExxonMobil for exercising its free speech rights and giving about $2 million to global warming skeptics. 

Still, the Greenpeace report is already receiving scrutiny in Washington, where Rep. Brad Miller, a North Carolina Democrat, has joined the environmentalist group in calling for Exxon to release its plans for contributions during the current year.

"The support of climate skeptics, many of whom have no real grounding in climate science, appears to be an effort to distort public discussion about global warming," Miller said. "So long as popular discussion could be about whether warming was occurring or not, so long as doubt was widespread, consensus for action could be postponed."

Incredibly, at these spending rates, skeptics are getting outspent by AGW supporters something like 1000:1 or more.  It is astounding that AGW supporters, with such a huge funding and publication advantage, still feel threatened by critics.

Climate research, once a sleepy academic backwater, is now a multi-billion dollar industry.  This boom in spending is because of fears of AGW, and should AGW theory be discredited, this funding will quickly dry up.  So funding for climate researchers exists only as long as climate researchers beat the drum that AGW is a large threat.   It strikes me that this is at least as large an incentive for bias as that of any Exxon-funded skeptic.   Here’s another way to look at it:  If AGW theory is proven correct, the likely political response might cut Shell’s revenues by 20-30%, at most.  If AGW theory is proven incorrect, then university climate research funding might be cut by 100%.   Directionally, all the incentives in academia are to inflate global warming projections.  No one is going to make the news, or even continue to get funding, if they argue that warming will only be a degree or two in the next century.  The guys that get the fame and the grants are those pushing the numbers higher and higher.

Certainly AGW supporters claim that academic researchers are only concerned about the science and are not concerned about the funding incentives.  This may be true (though a bit naïve, for anyone who has been in a university environment and sought research funding), but if pro-AGW researchers are not swayed by the funding, then it should be equally true that AGW skeptics are not swayed by much smaller amounts of money flowing to them.    Any argument that tries to claim that these situations are somehow different just ends up being circular, i.e. “it’s OK if our guys do it because our guys are right.”

One of the mistakes the IPCC process has systematically made is to make the lead author’s and reviewers of many of its report sections a scientist whose research is mostly in that area.  While this makes a certain sense, as these people will be expert in their particular area of review, it presents them with a huge conflict of interest.  For example, Michael Mann used his own historical temperature reconstructions as the lead analysis in the section of the third IPCC report for which he was lead author.  Clearly, one wouldn’t expect him to be (nor was he) open to any research or issues or criticisms aimed at his own work.  In the fourth report, the new lead author who replaced Mann on this section (Biffra) did the exact same thing Mann did – used his own work as centerpiece of the section, and has refused to even consider criticisms about that work. 

Just to avoid future argument, I will outline my potential biases.  I own a small recreation business which depends on people traveling to beautiful, natural settings.  I lose business when the climate changes (e.g. when lakes dry up next to my facilities, which has happened to me).  I generally gain