DiCaprio's The 11th Hour: We are the Most Important Generation in History
Ronald Bailey | August 16, 2007, 11:38am
Millenarianism has a venerable history in the West traced back to early Christians who anxiously anticipated an imminent Last Judgment and the advent of a "new heaven and a new earth" (Rev. 21:1).
This Western predisposition to millenarianism spawned various sects including the Anabaptists and the Hussites in Central Europe, the Rappites and the Millerites in 19th century America, and more recently the Jehovah's Witnesses. The Millerites of upstate New York were one fairly typical millenarian sect. In 1818, William Miller, the group's founder, calculated that Christ's Second Coming would take place during the next 25 years. Spectacular meteor showers and a huge comet were taken as unmistakable portents of impending disaster. After several missed dates, Miller finally predicted that the end would definitely come on October 22, 1844. One the appointed day many believers, dressed in white robes, climbed nearby hilltops to await the apocalypse. "The Great Disappointment" is how the Seventh Day Adventists, the modern successors of the Millerites, characterize Miller's prophetic failure.
In the 19th century, millenarian aspirations, originally spiritual and religious in character, became secularized and were incorporated into the doctrines of radical and utopian politics. The greatest millenarian political faith is Marxism. Like the religious millenarians who preceded him, Marx believed that a corrupt society--in his case, capitalism--would collapse in a massive crisis ushering in a golden age of egalitarian harmony. But instead of sin, according orthodox Marxist eschatology, the internal class contradictions of capitalist production doom that hateful (sinful?) form of society to inevitable destruction.
That hasn't happened, but the millenarian impulse did not die out in the West. For many modern leftists the "global environmental crisis" became the new agent of history that will eventually destroy capitalism. In the reinterpreted radical vision, capitalism, instead of strangling itself to death on its class contradictions, will choke to death on its own wastes.
Just a couple of examples--In his 1990 book, Remaking Society: Pathways to a Green Future, self-described social ecologist Murray Bookchin argued that we must change our repressive industrial capitalist society into "an ecological society based on non-hierarchial relationships, decentralized democratic communities, and eco-technologies like solar power, organic gardening and humanly scaled industries." Earth First! founder David Foreman asserted in the 1991 book, Defending the Earth, that Western society is "rotten to the core" and said that he planned to build "an egalitarian, decentralized, ecologically sound" society that would "emerge out of the ashes of the old industrialized empire" after the ecological apocalypse.
I am NOT saying that these people were orthodox Marxists, but that they (and many others) were the intellectual heirs to that form of secular millenarianism's deep antipathy to capitalism and industrial society. As the Institute for Social Ecology notes of Bookchin:
"During the 1950s and ‘60s, Bookchin built upon the legacies of utopian social philosophy and critical theory, challenging the primacy of Marxism on the left and linking contemporary ecological and urban crises to problems of capital and social hierarchy in general."
So why am I going on about this? Intellectual tendencies bleed over unconsciously into the popular culture. Prius-driving Hollyward star Leonardo DiCaprio will release his feature length documentary, The 11th Hour, this weekend. The 11th Hour is a popularization of early 21st century ecological millenarianism. From the press release:
The 11th Hour documents the grave problems facing the planet's life systems. Global warming, deforestation, mass species extinction, and depletion of the oceans' habitats are all addressed, and their causes rooted in human activity. The combination of these crises call into question the very future not of the planet, but of humanity.
And like most millenarian visions, DiCaprio's offers a way out for the faithful. In this case, by calling "for restorative action through a reshaping of human activity." But what I find fascinating about millenarian thinking is that the end always going to arrive for this crucial generation. Consider these soundbites from The 11th Hour's trailer:
Will our pivotal generation create a sustainable world in time?
Five hundred years out, people look back at this time: This was our finest hour.
What a great time to be born! what a great time to be alive! Because this generation gets to completely change the world.
This kind of generational moral self-flattering has always been thus.
For example, environmentalist Bill McKibben wrote in his 1989 book, The End of Nature:
“We just happen to be living at the moment of when carbon dioxide has increased to an intolerable level. We just happen to be alive at the moment when if nothing is done before we die the world’s tropical rain forests will become a brown girdle that will last for millennia.”
Canadian uber-environmentalist David Suzuki in 1992, declared,
“We are the last generation on Earth that can save the planet.”
So why do so many people in the developed world believe in apocalyptic environmentalism? The attraction of apocalyptic thinking is strong. One self-described survivor of millenarian environmentalism, novelist Eric Zencey, recalled in his 1988 essay, “Apocalypse and Ecology”:
"There is seduction in apocalyptic thinking. If one lives in the Last Days, one’s actions, one’s very life, take on historical meaning and no small measure of poignance … Apocalypticism fulfills a desire to escape the flow of real and ordinary time, to fix the flow of history into a single moment of overwhelming importance.”
Daniel Cohen, author of the 1973 Waiting for the Apocalypse, believes that every generation grows up convinced that it is the last generation in history. However, the method by which the end brought about changes. For Cohen’s generation nuclear war was the agent of the apocalypse.
“We believed passionately that there would be such a war, and like the early Christians we were sure that this Judgment Day would come within our lifetimes.”
Interestingly, unlike the Millerites, when prophesies of environmental doom fail, ecological millenarians do not experience a "Great Disappointment." As Daniel Cohen noted,
"One clearly wrong prophecy, or even a whole string of them, rarely discredits the prophet in the eyes of those who believe in prophecy."
As DiCaprio's new film shows, a lot people still want to think of themselves as living at the hinge of history in which their lives will make all the heroic difference for all the time to come.
But the truth is that our ancestors bequeathed to our generation a world that is immeasurably richer, cleaner and healthier than the one they lived in. I haven't seen The 11th Hour yet, but I suspect that it is not going to recommend those policies that have in fact improved the state of humanity for the last two centuries. Of course, it must be admitted that along the way there were some mostly unavoidable side effects on the natural world that arose as hundreds of millions of people clawed their way out of poverty. That being said, I will be happily surprised if The 11th Hour comes out in favor of strengthened property rights, expanding globalization, increasing urbanization, and spreading modern farming techniques. It is exactly those trends abetted by democratic capitalism that are improving humanity's estate and will help preserve nature.
So finally, I, too, may be something of a millenarian. Why? Because I believe that the future of humanity and the natural world is very bright. The 21st century will be the century in which the Great Ecological Restoration begins as the technological progress fostered by capitalism enables humanity to increasingly dematerialize our economy, allowing us to restore and withdraw from nature.
Ron Bailey | August 16, 2007, 2:18pm | #
Mr. Nice Guy: I'm not sure that this is responsive to your comments, but it turns out that the ideological environmentalists were scientifically and economically wrong about a whole list of alleged other catastrophes which I have listed ad nauseum. For one version, see my congressional testimony
here.
The essential feature of nearly all environmental problems is that they occur in open access commons. That includes everything from the Pleistocene
kill-off of the megafauna to global warming today.
The best technology humanity has ever invented for handling commons problems is privatization. that is, making people responsible for both the benefits and costs of an activity. See for example, herding versus just running around and killing off random deer and mammoths. A Pleistocene hunter couldn't just leave a mammoth alone because the next guy might come along and kill it and then first guy would be out of luck. Of course, it turns out that herding without fences doesn't work either as population grows, so then fence property to manage herds better and internalize costs. Modern fisheries are in the same state as the Pleistocene megafauna (a fisher can't leave a fish in the sea because the next guy will get it). So if we want to save fisheries privatization (fencing them in and assigning property rights to the catch to specific owners) is the only way to go.
Air pollution and water pollution are also commons problems--if you can't privatize due to high transactions costs--then regulation is necessary, and depending on the characteristics of the particular pollutant markets (SO2) will work well or perhaps tech standards might be necessary (catalytic converters). In any case, you can be sure because market signals don't exist for these unprivatized commons, the government regulators will rarely set the price of a pollutant at its true social cost. See most EPA regulations of alleged synthetic carcinogens as examples.
Consider the case of water today--the main problem is that governments around the world are vastly subsidizing the waste of water and ignoring how privatization can get
water to the poor and conserve it for nature.
All right, I've bored you enough. Just remember all environmental problems occur in open access commons and private property is the first thing you should consider for solving that problem. Again, forests are regrowing in countries where private property rights are strongest.
Neu Mejican: joe said there were extremists on both sides, so I quoted a couple enviro extremists as evidence.
Mark Bahner | August 17, 2007, 9:47pm | #
You seem to have a problem with the IPCC scenarios not being scientific predictions. But that is not their purpose. They are thought experiments/toy models used to help plan policy.
That's complete nonsense. The IPCC projections are pseudoscientific rubbish, meant to scare the public and policymakers into supporting reductions in CO2 emissions. They are exactly like the "Limits to Growth" series of scientific frauds.
Beyond question--or perhaps you question this?--the most important question the IPCC can answer in order to "plan policy" is, "How much will the world warm if governments don't intervene to reduce global warming agents?"
Now go read the IPCC Fourth Assessment Report Summary for Policy Makers Table SPM-3:
Table SPM-3
And all the other junk in AR-4...
http://www.ipcc.ch/pub/reports.htm
...and answer these assertions about the warming in the absence of government intervention, in 2090-2099, relative to 1980-1999, with "yes," "no," or "don't know":
1) The IPCC thinks there is more than a 1percent chance of warming more than 6.4 deg C.
2) The IPCC thinks there is more than a 10 percent chance of warming more than 6.4 deg C.
3) The IPCC thinks there is more than a 50 percent chance of warming more than 6.4 deg C.
4) The IPCC thinks there is more than a 99 percent chance of warming more than 6.4 deg C.
5) The IPCC thinks there is more than a 1percent chance of warming less 1.1deg C.
6) The IPCC thinks there is more than a 10 percent chance of warming less than 1.1 deg C.
7) The IPCC thinks there is more than a 50 percent chance of warming less than 1.1 deg C.
8) The IPCC thinks there is more than a 99 percent chance of warming less than 1.1 deg C.
Neu Mejican | August 18, 2007, 2:31am | #
rob,
I shall quote you.
When joe starts whinging on about the overall casualties from all sides, as though his faux-angst makes him a better (more "complete") person, it makes him an armchair general by revealing him as the sort of person who not only shows a profound lack of understanding of the realities of WW2, but of human warfare throughout history.
Like I said, my real problem is with people who (like joe) delusionally believe that wars can be fought without killing noncombatants (or that victory can be achieved with a minimum of noncombatant deaths). The reality of war is that there's simply no way to avoid such horrors, and history bears this out repeatedly.
Read this carefully and tell me that if I replaced the word "joe" with the word "rob" whether you would be pissed off at the clearly unflattering characterization of your position.
Your problem is with joe's position (you state it clearly), but you project that position into weakness of character in joe in all of your comments. This is both unwarranted (reasonable people
can disagree), and intentional on your part. You want to bolster your argument using arguments that attack the character of those that disagree with you. You, however, see the same tactic as a weak rhetorical trick when others employ it against you.
I disagree with you regarding both the implications of joe's statements, and with your take on the implications of your own statements.
Your lack of personal insight is impressive, but it does not make you more rational. Your tenacity in attacking joe's clear arrogance is fueled by something other than disagreement with his positions. It is personal for you. Your unwillingness to admit this is a sign of personal weakness on your part. (That is why I freely call you a pussy for whining about the reaction to your insulting and baiting language). joe is a chump to get worked up over anything you say, but that is tangential to our discussion.
I am, by the way, insulting you with this comment and many of the others I have made here.
I am doing it deliberately because your overall tone in debates is, despite your lack of profanity, indistinguishable from joe's...you both are arrogant and abusive, and quick to jump to a faux "victim" stance in a debate.
Me. I am just arrogant and flip, and enjoy thinking about issues (including the social dynamics of opponents in blog comment threads) in an interactive environment. The discourse we have had on this topic has told you very little about my true personality. I don't pretend I know anything about yours. I do know, however, that you are clearly unaware of many of the implications of the words you write on this blog.
I hope I am more aware of the impression I give with my clearly pedantic, overly twaddleknockish discourse. I don't take reactions to it personally. And I don't fault people for getting angry at it.
I have called you a disingenuous, self-deluded pussy in this thread a few times. I would hope that got some sort of rise out of you. I don't pretend that it makes me better than you. It might even make you better than me.
But who is more honest?
Neu Mejican | August 18, 2007, 1:44pm | #
Mark B.,
I have never claimed expertise in the area.
In terms of climate science, I am a moderately well read layman. I do my "serious work" in totally unrelated areas.
You, however, claim a low level expertise in the area (a master's degree in environmental engineering isn't it?).
Why not use your greater expertise to answer those questions for me. I would read your answers with interest.
I will stick with my position that you are misreading the purpose of the IPCC scenarios. To quote: “Scenarios are images of the future or alternative futures. They are neither predictions nor forecasts.”
The IPCC does not do science. It summarizes science and puts together policy documents. Or am I missing something?
But your take on things, to quote:
"In my opinion, the fact that 'there are no predictions by the IPCC at all' constitutes scientific fraud. Specifically, as I have written on my blog:
"The IPCC Third Assessment Report's (TAR's) projections for methane atmospheric concentrations, carbon dioxide emissions and atmospheric concentrations, and resultant temperature increases constitute the greatest fraud in the history of environmental science."
Is clearly hyperbole and it would take a bit of serious work on your end to convince me that you have a serious point.
Feel free to interpret my unwillingness to take up your challenge as validation of your position.
Or maybe you could just make your case rather than issuing challenges. You might be surprised at how much better that works.
For instance. I like your fish tagging idea. I worry about the potential impact on larger fish eating a bunch of radio tag chips, but that is a detail that can be studied and solved. Some genetic mark seems to avoid that, but makes it more difficult to collect fees.
Mark Bahner | August 18, 2007, 2:50pm | #
I have never claimed expertise in the area.
In terms of climate science, I am a moderately well read layman. I do my "serious work" in totally unrelated areas.
Yes, I was already basically certain of that.
Here's a friendly bit of advice: If you're writing about an area in which you're a layman, don't advise people who make their living in the area in question to go "do a serious piece of work."
It tends to make the person to whom you're giving the advice think you're an ignorant, arrogant jerk.
Why not use your greater expertise to answer those questions for me?
Heh, heh, heh! Use my "...low level expertise in the area (a master's degree in environmental engineering isn't it?)" that I "claim," eh?
Tell you what, Neu Mejican (anonymous comments...the best sign of true class on the Internet)...why don't you go to people you respect for the answers, instead of someone you don't?
Why don't you ask...well, the good folks at Real Climate? Here's a nice place to start:
http://www.realclimate.org/?comments_popup=463
Why don't you go there, tell them you're a big admirer of theirs, and ask them if they could please label the following assertions as, "true," "false," or "don't know," based on the projections and supporting material in AR4:
1) The IPCC thinks there is more than a 1percent chance of warming more than 6.4 deg C.
2) The IPCC thinks there is more than a 10 percent chance of warming more than 6.4 deg C.
3) The IPCC thinks there is more than a 50 percent chance of warming more than 6.4 deg C.
4) The IPCC thinks there is more than a 99 percent chance of warming more than 6.4 deg C.
5) The IPCC thinks there is more than a 1percent chance of warming less 1.1deg C.
6) The IPCC thinks there is more than a 10 percent chance of warming less than 1.1 deg C.
7) The IPCC thinks there is more than a 50 percent chance of warming less than 1.1 deg C.
8) The IPCC thinks there is more than a 99 percent chance of warming less than 1.1 deg C.
Or, you could go to the Nature Climate Feedback blog, and ask Dr. Trenberth, Dr. Heffernan, or anyone else with a climate science background to label the assertions as "true," "false," or "don't know."
Somehow, even though they were asked to do so--twice! by different people!--neither Dr. Trenberth nor Dr. Heffernan has been able to label those simple assertions as "true," "false," or "don't know."
A simple request, made July 12, 2007Mark Bahner | August 18, 2007, 5:54pm | #
Oh, brother. Dan Quayle was so right...what a waste it is to lose one's mind.
It's sad to see people who seem otherwise intelligent (like you, "Neu Mejican"...if that really is your name ;-)) seemingly unable to grasp fundamental science when it comes to climate change.
You tell me that:
You seem to have a problem with the IPCC scenarios not being scientific predictions. But that is not their purpose. They are thought experiments/toy models used to help plan policy.
But then you can't even read the SPM (that's SUMMARY for POLICYMAKERS) and label these 8 simple assertions as "true," "false," or "don't know."
1) The IPCC thinks there is more than a 1percent chance of warming more than 6.4 deg C.
2) The IPCC thinks there is more than a 10 percent chance of warming more than 6.4 deg C.
3) The IPCC thinks there is more than a 50 percent chance of warming more than 6.4 deg C.
4) The IPCC thinks there is more than a 99 percent chance of warming more than 6.4 deg C.
5) The IPCC thinks there is more than a 1percent chance of warming less 1.1deg C.
6) The IPCC thinks there is more than a 10 percent chance of warming less than 1.1 deg C.
7) The IPCC thinks there is more than a 50 percent chance of warming less than 1.1 deg C.
8) The IPCC thinks there is more than a 99 percent chance of warming less than 1.1 deg C.
Sigh.
Let me change my question then. Suppose that James Annan, a scientist specializing in climate prediction, said the answer to all those questions was "don't know."
http://julesandjames.blogspot.com/
In other words, James Annan, a scientist specializing in climate prediction, can read the entire Fourth Assessment Report (AR4), and he doesn't know whether the IPCC thinks--absent government interventions to reduce climate change--that there's a 99+% chance of warming LESS than 1.1 deg Celsius in the 21st century, or a 99+% chance of warming MORE than 6.4 degrees Celsius.
Would you still say that the IPCC's projections are "used to help/plan policy"? How are they useful to "help/plan policy" if the answer to every single question is "don't know"?
Mark Bahner | August 19, 2007, 1:24pm | #
You seem to be missing the larger point regarding your 8 questions...
No, you're missing the larger point. It doesn't make an bit of difference what the ranges are for the individual scenarios, if one does not know the LIKELIHOOD of that scenario. If one don't know the likelihood of each scenario--and even the likelihood of forcing above all scenarios and below all scenarios--one doesn't know squat. (From the standpoint of actually making rational policy.)
Here are the scenarios, with the IPCC's "likely" (66 to 90 percent probability) warming range for each individual scenario, in degrees Celsius:
B1 scenario = 1.1 – 2.9
A1T scenario = 1.4 – 3.8
B2 scenario = 1.4 – 3.8
A1B scenario = 1.7 – 4.4
A2 scenario = 2.0 – 5.4
A1FI scenario = 2.4 – 6.4
But you don't know squat (from a rational policy-making standpoint) if you don't know what the likelihood is for each scenario.
For example, suppose there is a 100 percent certainty that the climate forcing will be LESS than the B1 scenario. Now suppose there is a 100 percent certainty that the climate forcing will be MORE than the A1F1 scenario. Wouldn't you agree that there would be very different policy responses for those two situations?
Remember that James Annan--a scientist who specializes in climate prediction--has written that his responses to all 8 assertions is "don't know." From reading all the information in the Table SPM-3, and all the supporting in the Fourth Assessment Report, he doesn't know whether the IPCC thinks there is a greater than 99 percent chance of warming less than 1.1 deg C, or a greater than 99 percent chance warming more than 6.4 deg C.
Forgive me, but I'll skip to the end of your comments, as you finally start to see the big picture. You write:
The most controversial assumption in the Wigley and Raper (2001) probabilistic assessment was the assumption that each SRES scenario was equally likely.
You're partially right. But it's not "controversial," Neu Mejican. It's blatantly and elementally wrong. To see why, let's look at methane concentrations (methane is thought to be second only to CO2 as a climate warming agent).
Here are the methane atmospheric concentrations up to 2005:
http://en.wikipedia.org/wiki/Image:Methane-global-average-2006.jpg
Now, go to AR4 Figure 10.26 and tell me whether the methane atmospheric concentration you think will be measured in 2010 is likely to be closer to one scenario or another. Or whether you don't have the slightest idea which scenario is going to be closer to the actual measurement 3 years from now.
This seems to be the type of analysis Mark is implying should be done (as far as I can gather, correct me if I am wrong).
You're getting warmer. You're actually pretty close.
I am, of course, assuming that Mark would figure out how to calculate the probability of each scenario, use the newer information, and come up with a projection.
No, you're getting colder again. There is no scientifically valid reason to use scenarios at all. The most proper and scientifically valid method to produce climate forcings would be to develop probability density functions for emissions and atmospheric concentrations of each of the forcing agents *individually.* For example, on the warming side: CO2, methane, black carbon, etc. Develop probabilistic projections for each INDIVIDUALLY. Then do the same on the cooling side: for sulfur dioxide, organic carbon, and so on.
Using scenarios is simply borrowing from the fraudulent Limits to Growth deception technique. The method (of the fraud) is to have a few (relatively unscary) scenarios that are realistic, and a much larger number of scary and unrealistic scenarios, and then dishonestly refuse to attempt to assign probabilities to the scenarios. Therefore, people who don't know any better--e.g. policymakers, laypeople, and even some scientists who are not specifically knowledgeable about likely future emissions-- pick a number somewhere in the middle, and assume the number near the middle is the most likely number.
And without estimates of probability, people also tend to look at the scariest scenarios, and think in terms of "Boy, what if that happened?!"...because the scientists haven't told them that the scariest scenarios have probabilities of happening that are 1-in-100, or even less.
To summarize: Wigley and Raper's 2001 paper is a definite improvement on the analysis in the 2001 Third Assessment Report. And it's even an improvement on the analysis in the 2007 FOURTH Assessment Report! (A good sign of pathological science.) But Wigley and Raper were blatantly and elementally wrong to assume that all scenarios have equal probablity of occurrence. That's like saying that the future is as unpredictable as a role of a die, or a future lottery number.
The fact that there hasn't been a subsequent follow-up improvement on the Wigley and Raper 2001 paper in Science (i.e., without the clearly wrong assumption of equal likelihood of all scenarios) indicates the deep pathology of the current state of climate science.
Neu Mejican | August 19, 2007, 3:18pm | #
Mark,
Fusion power generating electricity would make electric cars the norm. These would be robot cars by your prediction from an earlier thread (put this together and you get fusion powered robot cars). To be fair, you never claimed, as far as I know, that fusion power would be widely available by 2035. But the brief look I took at your website, you do make predictions based on the assumption that there will be vast technological improvements that will reduce the use of fossil fuels. Fusion seems to be your technology of choice.
Your predictions are based on a scenario that is different than any that are considered by the IPCC, but it is a scenario none the less, and one that seems exceedingly unlikely. It is my opinion that you overestimate the pace at which these technologies, both in autonomous computer controlled agents and fusion power will become widely available.
You also make what can only be termed ridiculous assumptions regarding GDP in the next 100 years (80 quadrillion is a big number). And you do this based on an admitted lack of expertise in economic modeling.
Now to be pedantic:
You're partially right. But it's not "controversial," Neu Mejican. It's blatantly and elementally wrong. To see why, let's look at methane concentrations (methane is thought to be second only to CO2 as a climate warming agent).
You are responding to a sentence from Chapter 10 of AR4, not to me. Sorry about the sloppy posting. I am surprised you did not recognize it given your familiarity with the AR4 and its weaknesses.
There is no scientifically valid reason to use scenarios at all.
And yet there is, really, no other way to do things. Any model will be premised on a set of assumptions which when put together into a package are essentially just a "scenario" that provides a context for prediction. You don't like the fact that the IPCC uses multiple models, but remember they are not doing the science, they are summarizing the science. The various scenarios considered are an attempt to synthesize the scientific work so that policy makers can make use of it.
Please clarify this for me:
The most proper and scientifically valid method to produce climate forcings would be to develop probability density functions for emissions and atmospheric concentrations of each of the forcing agents *individually.* For example, on the warming side: CO2, methane, black carbon, etc. Develop probabilistic projections for each INDIVIDUALLY. Then do the same on the cooling side: for sulfur dioxide, organic carbon, and so on.
Are you proposing a reductionist approach here?
Given the integrated nature of climate systems, why would a set of independent predictions be more useful than a set of predictions based on integrative models that vary systematically in terms of various important factors?
Neu Mejican | August 20, 2007, 12:15pm | #
Once last comment here.
Mark B has a problem with the IPCC approach that seems to center on the lack of probability assigned to the IPCC scenarios. He seems to feel (not to put words in his mouth) that this makes the scenarios useless for policy making.
I have a different take on this.
If you compare the 8 questions Mark posts with the table SPM3 you will notice that Mark is asking for 99% confidence that temperatures will be beyond a single value.
But if we use a 99% confidence interval, then table SPM3 would look quite a bit difference (it uses a 66% CI).
The result of demanding a 99% CI, given that it is the upper end of the projections that is more uncertain, is that each range for each scenario would include MUCH HIGHER projected values. In other words, it would be more likely to include "alarmist" values. A more common CI would be the 95% CI, but that too would include the more extreme values.
Because the IPCC is putting out documents for policy makers, choosing the 66% CI is the conservative choice, because it provides a narrower, more conservative estimate of the upper values.
Moving forward, it will be important to develop models with narrower 95% confidence intervals, but until that work is done, the IPCC would be irresponsible to use the intervals that include the alarmist values.
The choices the IPCC make in regards to this issue directly refutes Mark's charges, imho.
Mark Bahner | August 21, 2007, 12:02am | #
Once last comment here.
Mark B has a problem with the IPCC approach that seems to center on the lack of probability assigned to the IPCC scenarios. He seems to feel (not to put words in his mouth) that this makes the scenarios useless for policy making.
I have a different take on this.
If you compare the 8 questions Mark posts with the table SPM3 you will notice that Mark is asking for 99% confidence that temperatures will be beyond a single value.
Cold, cold! You're ice cold, Neu Mejican!
Let's return to when you were very warm...the Wigley and Raper paper of 2001. The Wigley and Raper paper of 2001 DID have predictions.
Specifically, here are the Wigley and Raper 5 percent, 50 percent, and 95 percent probabilities for temperature rise in 2100, relative to 1990, in deg C.
5 percent probability = 1.68 deg C,
50 percent probability = 3.06 deg C, and
95 percent probability = 4.87 deg C.
In other words, Wigley and Raper PREDICTED that there would only be a 5 percent chance of warming of less than 1.68 deg C by 2100, relative to 1990.
That's good. They made a PREDICTION. A falsifiable PREDICTION, rather than an unfalsifiable "projection." But the Wigley and Raper predictions were based on equal probability of all scenarios.
In contrast, the AR4 projections have absolutely no assessed probabilities for any of the scenarios. Therefore, the probability for the lowest scenario could be 100 percent, or the probability for the highest scenario could be 100 percent. Effectively, it is completely impossible to know what temperature increase the IPCC expects. The answers to all the questions are "don't know."
The IPCC AR4 "projections" effectively say absolutely nothing. They are much worse than the Wigley and Raper paper...which was already pretty bad, since it assumed all scenarios were equally probable, and simple observation of present trends shows that all the scenarios aren't equally probable.
Mark Bahner | August 22, 2007, 10:34pm | #
Like I said before. You seem to think the way the science is summarized in the AR4 is useless because they did not go beyond the available evidence and assign probabilities to each scenario.
No, the science as summarized in the AR4 is useless because it's NOT science. Wigley and Raper 2001 is at least science. That paper at least contains falsifiable predictions, even though the predictions are based on a premise that is already clearly false (i.e., that all scenarios have equal probability of occurring).
If the IPCC had said in AR4 (2007), "We have nothing better than Wigley and Raper 2001, because we've sat on our keisters for the last six years, rather than doing the amount of technical analysis that a class of undergraduates should be able to do in a week."...
...at least they would have been presenting science. But they actually BACKTRACKED from Wigley and Raper 2001, presenting "projections," rather than Wigley and Raper's 2001 predictions. Those "projections" are unscientific, because they aren't falsifiable. And they're also completely useless from a policy standpoint.
Look at Wigley and Raper, 2001. That paper says that there's a 50 percent chance of warming greater than 3.06 degrees Celsius from 1990 to 2100. Now look at AR4. There is a 50 percent chance of warming greater than what temperature? The answer is, "Don't know."
Now look at Wigley and Raper again. That paper says there's a 95 percent chance warming will be greater than 1.68 degrees Celsius. Now look at AR4 again. There is a 95 percent chance of warming greater than what temperature? The answer is, "Don't know."
The "projections" in AR4 are worthless, because they don't even attempt to provide a scientifically valid answer to the question, "What will be the temperature change during the 21st century, in the absence of intervention by governments to reduce climate change?”
Wigley and Raper (2001) at least answers that question. They say that there’s a 95 percent chance of warming greater than 1.68 deg C, a 50 percent chance of warming greater than 3.06 deg C, and a 5 percent chance of warming greater than 4.68 deg C. The only problem with their answer is that it’s based on a clearly false premise…that all the scenarios are equally probable.
I, on the other hand, don't see that as making their report either useless or dishonest.
The IPCC has failed to provide an answer to the most fundamental STARTING question: "What will be the warming if governments do not intervene to reduce emissions?"
How can the IPCC projections be useful if the answer to "What will the warming be?" is "don't know"?
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