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Saturday, October 17, 2009

Tim Lambert of Deltoid: Why Everything in Superfreakonomics About Global Warming Is Wrong

Why Everything in Superfreakonomics About Global Warming Is Wrong

Deltoid blog, October 16, 2009, by Tim Lambert

I reviewed Freakonomics when it first came out and really liked it. So I was looking forward to the sequel Superfreakonomics. Unfortunately, Levitt and Dubner decided to write about global warming and have made a dreadful hash of it. The result is so wrong that it has even Joe Romm and William Connolley in agreement.

So what went wrong? One possibility is that Freakonomics was superficially plausible but also rubbish, and it was only when they wrote about an area where I was knowledgeable that I noticed. But I don't think this is the correct explanation. I've read the journal papers on sumo cheating, Lojack and abortion and crime that they cite in Freakonomics and they are fairly represented. Superfreakonomics, on the other hand, misrepresents the scientific literature on global warming. The difference here is that the papers cited by Freakonomics were Levitt's own work and he understood them, while Levitt and Dubner do not understand the climate science literature. This by itself would not be fatal, but what has taken them off the cliff is the Freakonomics formula: "What you thought you knew about X is wrong!". If you want to apply this formula to global warming you can easily find many superficially plausible arguments on why the mainstream science is wrong. Bang those into your chapter on global warming without bothering to check their accuracy and the only work that remains is the tour to promote your book.

But enough on why they got everything wrong. Let's look at what they got wrong. My Global Warming Sceptic Bingo Card is a bit out of date but they manage to tick five boxes: global warming is a religion, ice cores show warming comes first, ice age predicted in the 70s, water vapour dominates and climate modelling isn't scientific. William Connolley stopped when he had found ten serious errors, so I'll continue where he left off and see if I can find ten more. To make it more of a challenge, I'm just going to look at the extract that appeared in the Sunday Times entitled "Why Everything You Think You Know About Global Warming Is Wrong" (not yet available from their website). And remember, this is on top of the ten serious errors that Connolley found.

Unless otherwise indicated all quotes are from the Sunday Times extract.

(1) "Yet [Ken Caldeira]'s research tells him that carbon dioxide is not the right villain in this fight."
Caldeira has exactly one quote on his home page:
"Carbon dioxide is the right villain," says Caldeira, "insofar as inanimate objects can be villains."
Joe Romm asked Caldeira about the misrepresentation of his views and he told Romm:
If you talk all day, and somebody picks a half dozen quotes without providing context because they want to make a provocative and controversial chapter, there is not much you can do.
(2) "Caldeira's study showed that doubling the amount of carbon dioxide while holding steady all other inputs -- water, nutrients and so forth -- yields a 70% increase in plant growth, an obvious boon to agricultural productivity."

That would be this paper. Look at the abstract:
Climate stabilization via "Geoengineering" schemes seek to mitigate climate change due to increased greenhouse gases by compensating reduction in solar radiation incident on earth's surface. In this paper, we address the impact of these climate stabilization schemes on terrestrial biosphere using equilibrium simulations from a coupled atmosphere-terrestrial biosphere model.
Climate stabilization would tend to limit changes in vegetation distribution brought on by climate change, but would not prevent CO2-induced changes in Net Primary Productivity (NPP) or biomass; indeed, if CO2 fertilization is significant, then a climate-stabilized world could have higher NPP than our current world. Nevertheless, there are many reasons why geoengineering is not a preferred option for climate stabilization.
So if CO2 fertilization is significant you get a 70% increase in plant growth. Levitt and Dubner turned that into "you get a 70% increase in plant growth". Note also that Caldeira used a climate model of the type that L&D said could not be trusted. And did you notice the last sentence? L&D simply ignore the reasons why Caldeira said that geoengineering is not a preferred option.

(3) "It is one thing for climate heavyweights such as Crutzen and Caldeira to endorse such a solution."
In the abstract above Caldeira writes:
there are many reasons why geoengineering is not a preferred option for climate stabilization.
This is not an endorsement. In a more recent paper:
A reduction in the amount of solar radiation (insolation) could rapidly mask the effects of global warming without a reduction in CO2 emissions, but the quick fix brings serious danger. An abrupt end to or failure of geoengineering could throw the climate into even greater turmoil, possibly leading to warming rates twenty times those seen today. ...

Decreasing emissions of greenhouse gases reduces the environmental risk associated with climate change. By contrast, continued CO2 emissions, even with the potential of geoengineering, will likely increase environmental risk. Thus, with respect to environmental risk, geoengineering is not an alternative to decreased emissions. Opponents of immediate climate mitigation actions might argue for a delay in emission reductions based on a lack of trust in climate model predictions. However, reliance on geoengineering implies a larger trust in climate model results than does reliance on emissions reductions. For example, even if there were only a 50% probability that climate model predictions are approximately correct, reducing emissions could be a prudent avoidance of risk. However, if we had only 50% confidence in climate model predictions of the efficacy of geoengineering schemes, then reliance on geoengineering is likely to be imprudent.
(4) Despite Caldeira being an expert on ocean acidification L&D say nothing about at all, perhaps because their cheap fix will do nothing about it. Caldeira writes:
Unless we cut greenhouse gas emissions very deeply and very soon, I think that Arctic ecosystems and coral reefs will be a thing of the past. These ecosystems may be just the tip of the melting iceberg.
We need to eliminate CO2 emissions -- about this there is no question in my mind. There is also no question but that CO2 emissions are increasing more rapidly than was anticipated in any of the IPCC emissions scenarios.

I do not see intentional climate intervention approaches as an alternative to CO2 emissions reductions, but it may be something we need to do to, for example, prevent great ice sheets from sliding into the ocean. These approaches may be able to partially save Arctic ecosystems but will do nothing to save coral reefs.
(5) "changes in carbon dioxide levels don't necessarily mirror human activity"
This is misleading. The change in CO2 levels since the industrial revolution is caused solely by human activity.

(6) "coal is so cheap that trying to generate electricity without it would be economic suicide"
So France committed economic suicide? Who knew?

(7) "it is already... Too late ... even if humankind immediately stopped burning all fossil fuel, the existing carbon dioxide would remain in the atmosphere for several generations."

Yes, we would get more warming even if all emissions stopped. But it is possible to keep the warming under two degrees. So it's not too late to reduce emissions.

(8) "The problem with solar cells is that they're black, because they are designed to absorb light from the sun. But only about 12% gets turned into electricity and the rest is reradiated as heat - which contributes to global warming."

This fundamentally misunderstands what is causing global warming. It is true that replacing coal-fired power plants with solar cells will produce similar amounts of waste heat, but global warming is not caused by the waste heat from fossil fuels but the enhanced greenhouse effect.

(9) "IV estimates this plan could be up and running in about three years, with a start-up cost of $150m and annual operating costs of $100m. It could effectively reverse global warming at a total cost of $250m."

Only if you think that you only need to run it for one year. In fact you'll have to keep running it for centuries.

And if you ever stop, you'll get all the prevented warming in a decade or so. What could possibly go wrong?

(10) "In 2006 [Paul Crutzen] wrote an essay in the journal Climatic Change lamenting the "grossly unsuccessful" efforts to emit fewer greenhouse gases and acknowledging that an injection of sulphur in the stratosphere "is the only option available to rapidly reduce temperature rises and counteract other climatic effects."

By now you may have noticed that L&D systematically misrepresent their sources, and sure enough, if you look at Crutzen's essay you find:
By far the preferred way to resolve the policy makers' dilemma is to lower the emissions of the greenhouse gases. ... although by far not the best solution, the usefulness of artificially enhancing earth's albedo and thereby cooling climate by adding sunlight reflecting aerosol in the stratosphere might again be explored and debated ...

If sizeable reductions in greenhouse gas emissions will not happen and temperatures rise rapidly, then climatic engineering, such as presented here, is the only option available to rapidly reduce temperature rises and counteract other climatic effects.

Finally, I repeat: the very best would be if emissions of the greenhouse gases could be reduced so much that the stratospheric sulfur release experiment would not need to take place
Far from endorsing it as a cost effective solution, Crutzen was suggesting it be researched as a last-ditch measure if his preferred option fails.

Well, that's my ten, but UCS and Joe Romm have found even more stuff that is wrong.

The response from Dubner so far is pathetic:
While Dubner, who also writes a popular New York Times blog with Levitt, dismissed Romm's post in an email to me yesterday as "hard to take seriously," he also assumes that "there will be debate and legitimate pushback against that chapter in our book."
Link to blog post:

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