I see Andrew Dessler has not yet taken me up on my Fabulous Free Money Offer. Nor has he answered even the most basic of my questions.

For example, he wrote he found my estimates for anthropogenic CO2 emissions “amusing,” because he claimed that there was “no evidence” that anthropogenic emissions of CO2 would peak circa mid-century, as a result of normal technological development.

I responded by asking if he was aware of the IPCC “B1″ scenario? As anyone can see, CO2 emissions under the “B1″ scenario peak circa mid-century:

http://www.grida.no/climate/ipcc_tar/wg1/figts-17.htm

In fact, CO2 emissions ALSO peak circa mid-century under the “A1T” scenario.

So how about it Dr. Dessler? How was your statement anything but a bald-faced lie? Were you truly not aware of either the “B1″ or “A1T” scenarios?

I’m especially interested in your answer to this question, given your comment only one day earlier that, “I’m not sure I know what role science plays when dealing with people (e.g., Singer) who make transparently false scientific arguments.”

How was your statement anything but a “transparently false scientific argument?” Does this mean that you do not know what role science plays in dealing with people like yourself?

See my weblog post:

“I will give an additional $10 (so now we’re up to $40, total) for your CERTIFIED BEST EFFORT predictions of atmospheric methane concentrations every decade from 1990 to 2100. I want them in the same format as your other predictions, i.e., “5% probability, 50% probability, 95% probability”. See my Fabulous Free Money Offer of yesterday for details.

One more thing…an important clarification: I want your predictions to be in the same conditions as mine and the IPCC’s…without government mandates for GHG emission reductions.

Again, if you are at all uncertain about any of the conditions for these fabulous offers of free money, please ask me questions.”

I responded that I don’t support mandatory reduction of GHG emissions, and provided 9 scientific claims to support my argument.

Andrew Dessler responded…

…oh my! Well, I don’t have time to address all he wrote, so I’ll focus on two items (item numbers 3 and 4 from my nine claims).

I wrote, “3) A preponderance of evidence suggests that CO2 emissions will peak circa mid-century, or earlier, and will decline by the end of the century to a value that causes atmospheric concentrations to plateau at a value below 560 ppm (i.e., double pre-industrial concentration). This will happen through normal technological evolution…”

He responded, “Some of your points are scientific, but they have no merit. I was especially amused by number 3, that CO2 will peak mid-century w/o any policy to reduce GHGs. You say the “preponderance” of evidence supports you, when I think “no evidence” would be more appropriate.”

Good grief. Are you serious that you truly know of “no evidence?!” Are you familiar with the concept of a “Kuznets curve?” If so, do you understand how subsequent Kuznets curves for countries that develop later and later peak at lower and lower incomes, and have smaller and smaller “bump” heights? Also, when I mentioned Jesse Ausubel, it was clear that you had no clue who he even was. Have you even bothered to study his work on “decarbonization” since we last discussed the issue? Finally, have you carefully read the work of Ray Kurzweil? Have you read Arnold Kling’s commentaries on the implications for economic growth of Ray Kurzweil’s work? What about the work of Robin Hanson? (I would ask if you’ve read my own work on the subject, but it’s pretty clear from the tone of essentially all your remarks that you would consider it to contain nothing of value.) Finally, and most astoundingly, are you ****not even aware**** of the existence of the IPCC TAR “B1″ scenario??

I tell you what…on my own weblog, I have made you another Fabulous Free Money Offer. (However, this time I’m going to try to define the terms of the offer more clearly, so that we don’t end up with the situation we had last time, when you demanded payment before you had fulfilled the conditions of the offer.) Please see my weblog for details, but basically, I’m offering you $10 if you can correctly answer two questions, and give me your scientific analysis on the third question. The three questions are:

1) What were the approximate worldwide per-capita industrial CO2 emissions (i.e., from the consumption and flaring of fossil fuels) in 1950, 1955, 1960, 1965, 1970, 1975, 1980, 1985, 1990, 1995, 2000, and 2005?

2) What are the worldwide per-capita CO2 emissions projected in the IPCC TAR for the years 2030, 2050, 2070, and 2100 under the following scenarios: A1F1, IS92a, B2, and B1?

3) What is your scientific opinion of the implications, if any, of the correct answers to those first two questions?

I’m offering you an additional $10 to provide your BEST estimate values for worldwide industrial CO2 emissions (i.e., not including land use changes) every decade from 1990 to 2100, in the form of 5 percent probability, 50 percent probability, and 95 percent probability estimates. (The meaning of the probability numbers is that that’s the probability that the number will be BELOW the value you estimate. Please see my weblog, and ask if you require further explanation.) I want to emphasize that I want your BEST estimates. I don’t know if Texas A&M has an honor system, but before I give you any money, I want you to certify, on your honor, that the estimates are the BEST you can come up with at present.

I wrote, “4) The resultant temperature increase (approximately 90% probability of lower tropospheric temperature increase from 0 to 2.2 degrees Celsius above current value) will be such that a preponderance of evidence supports either minimal net harm, or even net benefit.”

He responded, “We discussed your number 4 before, so you know I think it’s balderdash. I won’t repeat that discussion here.”

Yes, we have indeed discussed this before. But have you ever even considered the possibility that you think my work is “balderdash” because you are in error, rather than I?

I am offering you another $10 (that’s $30, total) if you will provide me your BEST estimates of average temperature changes in the lower troposphere (as measured by satellites) every decade from 1990 to 2100. I also want them in the form of “5 percent probability, 50 percent probability, and 90 percent probability” estimates. Please see my weblog for details.

http://markbahner.typepad.com/random_thoughts/2006/02/fabulous_free_m.html

This is a difficult question. I’m not sure I know what role science plays when dealing with people (e.g., Singer) who make transparently false scientific arguments.

If I assume the real issue is greatly divergent values — in other words, Singer et al. make false scientific arguments because his values lead him to oppose action on mitigation, and he can most easliy achieve that objective by making false scientific agruments — then I’ll refer you to my comment up above:
Science is one input to a policy debate. I would argue that as values diverge, science has less and less of a role to play. If values diverge enough, then agreement is difficult or impossible, even if there is total agreement on the science (e.g., abortion). The flip side is that where values agree totally, then arguments about science completely determine action (e.g., tornado).

For the group you proposed, it might be that our values are so divergent that no agreement is possible. I don’t know. In that case, science is not doing much. Luckily, I think the values of the general public are becoming more aligned than your proposed motley crew (crüe?), and an agreement is possible.

Regards.

You wrote:
If a decision to reduce GHGs is a polictical decision (agreed), a function of normative commitments, in your framework how is it even possible that you can make a “scientific” justification for action? If as you say science provides answers to positive question, how can it than transorm into answers to normative questions?

Let me completely clear about my justification. As a citizen, I believe that we have a moral obligation to leave the Earth as close as possible to how we found it. As a scientist, I know that the Earth is warming, humans are likely to blame for the recent warming, and that the warming will continue into the foreseeable future as GHGs build up in the atmosphere.

Thus, a combination of my judgments about what is right and my knowledge of science leads to my judgment that the countries of the world should reduce GHG emissions.

While science plays a role in my decision (it answers the questions that are important in my decision), science does not by itself compel action.

Regards.

Your post exemplifies the confusion between science and values.

Number 5, for example, is an argument about morality. Science tells us nothing about the moral choices that you describe.

Numbers 7 and 8 take a cost-benefit viewpoint. Such a view is also a moral choice. Cost-benefit analyses ignore the rights of future generations to inherit a clean environment, ignore the costs of low probability catastrophic events delayed far into the future, as well as the possibility of completely unforeseen “climate surprises”, and it provides no guidance about the ethical issues of climate change. While you can argue that we must consider costs and benefits, I can argue that we must also consider what’s the “right” thing to do from an ethical perspective. And there are practical issues, such as whether exponential discounting is appropriate for costs so far in the future.

Number 6 is similarly also a value judgment.

All of these value judgments are not addressable by science, so your challenge for me debunk them is ill posed.

Some of your points are scientific, but they have no merit. I was especially amused by number 3, that CO2 will peak mid-century w/o any policy to reduce GHGs. You say the “preponderance” of evidence supports you, when I think “no evidence” would be more appropriate.

We discussed your number 4 before, so you know I think it’s balderdash. I won’t repeat that discussion here.

I could go on, but I won’t.

Regards.

If a decision to reduce GHGs is a polictical decision (agreed), a function of normative commitments, in your framework how is it even possible that you can make a “scientific” justification for action? If as you say science provides answers to positive question, how can it than transorm into answers to normative questions?

If science – politics are separate, then how can science justify one action over another?

You misunderstand several aspects of the discussion. Let me go through them point-by-point:

You write:
The question of what actions, if any, would be “effective” is surely a question of science — including the same science that tries to estimate the relationship between carbon dioxide gas levels and global temperatures.

Please re-read Roger’s and my post to correctly understand my response. I said that he was describing a political strategy to reduce GHGs, not provding a scientific argument against GHG regulation.

You write:
As for value judgments vs. discounted present values, this is a red herring. The issue is human welfare, the obverse side of which is human misery.

You’ve simply transfored the value judgment issue into how to define “human welfare.” Some people would take the view that human welfare and economic wealth are equivalent, while others would contend we have other moral and ethical responsibilities (e.g., the Evangelicals). Perhaps you agree with the former position, but you should not assume everyone else agrees with you.

You write:
I suggest Dessler live in a Third World slum for a couple of years without outside assistance, and then say the choice between poverty and temperature is a value judgment.

Straw man. Our choice is not between temperature increase and third-world poverty. This is the kind of unrealistic argument that drives gridlock in the debate.

Regards.