Arnold Kling  

Some Responses on Global Warming

Brockman, Mind-Changing, con't... One Property Rights, Many Reci...

The response to my global warming question has been mostly either bitter denunciation or support, but few answers. However, Anand Gnanadesikan understands what I am looking for. For example, he recommends this paper.

This study highlights the role of water vapor feedback in amplifying the global cooling after the eruption of Mount Pinatubo...the results described here provide key evidence of the reliability of water vapor feedback predicted by current climate models in response to a global perturbation in the radiative energy balance. Given the importance of water vapor feedback in determining climate sensitivity, such confirmation is essential to the use of these models for global warming projections.

He also points to this paper.

we explore changes in tropical Pacific circulation since the mid-nineteenth century using observations and a suite of global climate model experiments. Observed Indo-Pacific sea level pressure reveals aweakening of the Walker circulation. The size of this trend is consistent with theoretical predictions, is accurately reproduced by climate model simulations and, within the climate models, is largely due to anthropogenic forcing.

Comments and Sharing

COMMENTS (12 to date)
mjh writes:

I can't claim to understand all of this paper. But it still doesn't answer one important question to me: if water vapor is part of a positive feedback loop that causes higher temperatures than C02 alone can cause, then why in the past, when temperatures where higher than today and C02 levels were higher than today, did the climate not run away and become Venus? In other words, if the assumed positive feedback from water vapor exists, why hasn't it already kicked in?

Barkley Rosser writes:

I think I was one who provided neither bitter denunciation nor "support," although perhaps I was cast into the latter camp. I mentioned that albedo is a recognized source for positive, nonlinear feedbacks, working much like water vapor (I did not mention the latter, but am aware of it). I also mentioned some countervailing elements, if I remember correctly.

If you want some references on this, I can probably provide them, but am getting ready to go to New Orleans for the ASSA meetings, so a bit busy right now...

Ben Kalafut writes:

Perhaps you should have used Google Scholar (or the Real Climate 'blog or even Wikipedia) or talked to your local climatologists and read technical papers like these before contributing to the "false debate" problem.

I don't offer my opinion on economics without first reading up and seeing what the experts have to say. Physical scientists ought to be able to expect the same from you.

Matt writes:

Arnold's polite way of giving us a reading assignment!

Barkley Rosser writes:


Actually, I have worked with climatologists for over 30 years on this sort of modeling. The problems are twofold: too damned busy because getting ready to go to meetings in New Orleans, and too many possible sources and links. All I have said stands up and is defensible.

michael gordon writes:

Here, reprinted with a few changes, are some comments I left in the energy discussion section of Consumer Reports not long ago:

1) If climate specialists debate energetically the pros and cons of climate change --- including whether the planet is warming up unusually (compared to the era, say, between the 10th and 13th centuries), its causes, and its long-term consequences such as its severity etc --- then non-climate specialists and especially economists like Arnold or economist-political scientist lke me would be hard put to add anything substantive to their debate.

What we can do is maybe say some things of interest about the policy approaches that the climate science entails, on all side of their debate.

2) How so? Well, first and foremost for me as a specialist in international relations and security studies (as well as global political economy) is this:

Whatever your own view happens to be about global warming --- its seriousness, its causes, its implications for our climate and human life in the future --- it seems highly desirable for national security reasons for this country to move away from dependence on Middle Eastern oil suppliers . . . all politically vulnerable countries, ruled by kleptocratic coteries, whose importance to the global economy and to American national interests seem bloated way out of proportion owing to their oil resources. And though the US imports most of its oil from outside the Middle East --- from Indonesia, Venezuela, Nigeria, Canada, and Mexico --- the global oil market is an integrated one, and so it really doesn't matter if we ourselves are less dependent on Persian Gulf suppliers compared to Europe, Japan, and others. So . . . though most economists would want us to apply a strict cost/benefit calculus to subsidizing alternative fuel technologies --- as well as shifting to natural gas (which we have in abundance), itself less polluting in greenhouse gases than oil-based gasoline --- it seems that for national security reasons this kind of strict cost/benefit accounting needs to be qualified in this domain.

3) In the CR discussion, one knowledgeable forum member wondered why a cost/benefit analysis of the sort that economists use wouldn't be possible as the previous paragraph inicated.

My answer:

A sound point, Timothy --- and well put. Only . . . well, we're dealing with lots of imponderables and even more uncertainty about a lengthy future, say, three or four decades ahead, that make any use of rigorous cost-benefit analysis very difficult --- really, when you get down to it, little more than chucking some figures into the wind and snatching at those you are lucky enough to can get hold of.

What is clear can be set out concisely: except for the former Yugoslavia, all our military uses since the end of the cold war have been in the Persian Gulf area and the huge arc of instability running through it from Afghanistan, Pakistan, and Iran, and continuing through Lebanon, Israel, the Palestinian areas all the way into Somalia. Granted: there are other reasons why we're fighting in Afghanistan and Iraq against extremists and their terrorist threats to our country and our closest allies, but the whole arc --- encompassing nearly 20 countries --- is inflated in importance by the world dependence on Middle East oil. It's squarely in our national interest to deflate that importance, quite apart from climate change, by shifting away over a reasonable period of time --- say, a decade or so into the future --- and tapping natural gas here at home and encouraging innovation in alternative fuels (nuclear included). A strict cost-benefit calculus can't deal effectively --- only toss out rough guesses --- when it comes to factoring in massive uncertainty and totally unforeseen events like 9/11.

Essentially, to put it bluntly, virtually all economic analysis (and mainstream theories) projects incremental or at least linear change for the future, and though it can handle risk (stochastic: as in chess moves that can be programmed in computer software), it's at a loss when dealing with uncertainty involving high-order interests like national security.

Alternative scenarios, with subjective
probability estimates of their likelihood, are about as much as can be reasonably expected as policy guidance for any reasonable period into the future. And please note quickly. I only wanted to note the importance of encouraging innovative shifts in alternative fuels, and this forum, I'm sure you'll agree, really isn't the place to discuss foreign policy and grand strategy. So please excuse me if I pass a self-denying ordinance and turn out to be reluctant to say anything more along these lines.

(I then, somewhat unfairly, tried to boost my "authority" for these statements by noting that I had worked closely in grad school with Tom Schelling, the recent Nobel Prize-Winning economist who pioneered lots of our understanding of deterrence theory, bargaining strategies, tacit bargaining, arms control, and on and on. I repeat the unfair statement here, if Arnold lets me.)

Michael Gordon AKA The Buggy Professor

PS Almost forgot. Despite media hyperbole, what does seem to emerge fairly clearly from the global warming debate is that though temperatures rose somewhat from 1979 and the end of 1998 --- the latter the warmest year for about 60 years ---the average temperature of the earth has fallen from that peak and remained steadily over the last 7 years . . . no sign of any more warming.

True, it's hard to know what to make of a 7-9 year period of temperature. For that matter, it's no less true that finding an average meaningful temperature for the earth isn't at all easy either, or maybe even reliably possible. Anyway, for what it's worth, you might all enjoy these two links --- one to an article by a meterological specialist in the New Statesmen, and the other (surprisingly) published yesterday in the NY Times.

michael gordon writes:

I forgot to add another informative link, this one about how, surprisingly, the US since Bush's election in 2000 has noticably outperformed the EU-15 on average in reducing C02 emission, and performed at the same level for all greenhouse-gases.

From the WSJ, but linked to another source:

Michael Gordon, AKA the buggy professor

Matt writes:

I still like this one:

I think the key to watch is amount of ice left at the Arctic during summer. It is the arctic that acts as the temperature stabilizing system, and when the pole is ice free the arctic ice system is operating above capacity and cannot remove all the heat it needs to to keep equibrium.

James A. Donald writes:

These studies, the cooling after Mount Pinatubo, and the decline in the tropical pacific circulation, are just cherry picking. There are large fluctuations in all of these phenomena that are *not* explained by or consistent with climate models. Given a huge number of climate proxies, it is easy to construct a ransom note by selecting some data and not other data. How does the fact that the Antarctic is icing over, and the Northwest passage is closing again, fit in with climate models?

To assess global warming, need global data, which means satellite temperature measurements. Satellite temperature measurements are not consistent with positive feedback - they indicate global warming that is at most consistent with the extreme low end of the IPCC's range of models, and stretch even that

James A. Donald writes:

Ben Kalafut writes:
> Perhaps you should have used Google Scholar
> (or the Real Climate 'blog

For an analysis of the data provided on Real Climate, I recommend

Getting your information about global warming from Real Climate is like getting your information about evolution from the Baptist Church in San Antonio. They are basically bible thumpers.

Josh writes:

Regarding the first point on positive feedbacks of water vapor - even that one is "empirical" in the sense that you need climate models to see it, not in the more traditional sense. The problem is how you disentangle cause and effect in the climate system and if you imagine that the effect is actually the cause, you can easily create positive feedbacks. See Roy Spencer here:

Now, what we really need in the climate system is some big, non-cloud source of radiative forcing, where the cloud feedback signal is not so contaminated by the obscuring effect of cloud forcing. The only good example we have of this during the satellite era is the cooling after the 1991 eruption of Mt. Pinatubo.

And guess what? The SW cloud feedback calculation from the Pinatubo-caused variability in Forster and Gregory was – surprise, surprise! – anomalously negative, rather than positive like all of their other examples of feedback diagnosed from interannual variability!

Morgan writes:

Honestly ask yourselves,
Why do you dispute the danger of Global Warming? Are your reasons scientific? Or are your reasons based on the fact that Global Warming presents tremendous externality issues as well as possibly precluding your Utopian Economic System?

If its the latter, what does that say about your intellectual honesty? Should you have confidence in your conclusions in any part of your life if you tend to form opinions first and cherry pick theories and data that supports those opinions?

Comments for this entry have been closed
Return to top