Climate & Energy

Dealing with uncertain risks

Jim Manzi replies to Ryan Avent

The following is a guest essay from Jim Manzi, CEO of Applied Predictive Technologies (APT), an applied artificial intelligence software company. He writes occasionally for National Review and blogs at The American Scene. ----- Last week on this site Ryan Avent presented a thoughtful response to my recent article at The American Scene arguing against a carbon tax. Grist has graciously invited me to reply. As I understand it, Ryan had three basic criticisms of my logic: the impacts of global warming will be more messy, unpredictable, and heartbreaking than I let on, I don't understand the economic trade-offs that make a carbon tax an elegant solution to the problem, and the technology-focused approach to the problem I propose is insufficiently conservative. I'll try to address each of these in turn, all with a spirit of open-minded inquiry. The first objection highlights the fact that productive global warming debates almost always hinge crucially upon predictions of the future. Consider three generic types of predictions: deterministic ("If I let go of this pencil, it will fall"), probabilistic ("If I flip this coin, it has a 50% chance of coming up heads and a 50% chance of coming up tails"), and uncertain predictions, for which we can not specify a reliable distribution of probabilities ("There will be a military coup in Pakistan in 2008"). Economists will immediately recognize the distinction between probabilistic and uncertain forecasts as, in essence, Knight's classic distinction between risk and uncertainty. Strictly speaking, all predictions are uncertain, but as a practical matter we treat different predictions differently based on the observed reliability of the relevant predictive rules used to generate them. No serious person believes that even the physical science projections for climate sensitivity (i.e., how many degrees hotter the world will get if we increase atmospheric carbon dioxide concentration according to some emissions scenario), never mind our predictions for how fast the world economy will grow or the economic impact of various degrees of climate change, are deterministic. This is why climate modelers and integrated climate-economics modelers spend so much time developing probability distributions for various outcomes and combining possible outcomes via odds-weighting to develop expected outcomes. When we hear a modeling group say "the expected outcome is X," it doesn't mean they've assumed only the most likely scenario will occur; it does mean, however, they assume their distribution of probabilities is correct (not being idiots, of course they constantly work hard to try to test and improve this distribution of probabilities). For the moment, let's assume that predictions of global warming outcomes are probabilistic. I go into all this in my posts and articles in much greater detail, but if we take Nordhaus's DICE modeling group at Yale as a benchmark, we can make the following observations about global warming:

Greenland ice sheet is meeeelllting, it’s meeelllting!

The Greenland ice sheet is melting at an alarming rate! As in, faster than it has since satellite measurements began in 1979, and with 10 percent more melting in 2007 than in the previous record year of 2005. Allow researcher Konrad Steffen to put it into perspective for you: “The amount of ice lost by Greenland over the last year is the equivalent of two times all the ice in the Alps, or a layer of water more than one-half mile deep covering Washington D.C.” Yes, we think that qualifies as alarming.

The land down underwater

What happens to a woman without a country?

By Amanda McKenzie, national coordinator of the Australian Youth Climate Coalition. ----- Along with 10 other young Australians, I traveled to Bali to bring the voice of Australia's youth to the U.N. Climate Change Conference. We have been reminding world leaders that our future is threatened. However, my personal concerns about my future were eclipsed when a young woman named Claire from the small island nation of Kiribati stood up in front of 200 international youth and told her story. For Claire, climate change is more than a future concern. It is right here, right now. Youth from all over the world, including Australia, had come together to share their stories and successes in raising awareness and taking action on climate change in their home countries. Every participant was humbled by Claire, who offered her heartfelt thanks to all of us for our efforts. Her home, only two meters above sea level, is rapidly being inundated by the rising ocean. Two islands that make up Kiribati have already been submerged. Claire's island, home, culture, and future are all under imminent threat from climate change. It is likely that her entire nation will have to be evacuated in the near future. Where do you go when your country simply vanishes? Claire's voice, and the voices of the Pacific, are largely absent from the U.N. Climate Change Conference. These nations are small in terms of their size, population, wealth, and greenhouse-gas emissions. That's the irony: those who have contributed the least -- and benefited the least from the extraction and burning of fossil fuels -- will suffer first. Kiribati will be underwater before the bulk of the Australian population realizes that climate change is the most serious issue on the planet.

Notable quotable

“And we ought to declare that we will be free of energy consumption in this country within a decade, bold as that is.” – Mike Huckabee, Republican presidential candidate, 10 Dec. 2007 [UPDATE: It appears Huckabee was misquoted in an early draft of the transcript. His quote now reads, "And we ought to declare that we will be oil free of energy consumption in this country within a decade, bold as that is." That doesn't make a ton of sense either, but at least it's a little more clear what he's getting at. He wants to eliminate our use of …

House report condemns “systematic” Bush admin climate-science manipulation

“The Bush administration has engaged in a systematic effort to manipulate climate change science and mislead policymakers and the public about the dangers of global warming,” concludes a report from the House Oversight and Government Reform Committee. The report, written by the Democratic majority, is the product of a 16-month investigation into the Bush administration’s alleged climate-science tampering, including accusations that it edited climate scientists’ testimony to Congress, limited the public’s access to government climate scientists, suppressed scientific views out of line with the administration’s, and edited climate documents to emphasize uncertainties and play down humans’ role in climate change. …

Beyond the point of no return

It’s too late to stop climate change, argues Ross Gelbspan — so what do we do now?

As the pace of global warming kicks into overdrive, the hollow optimism of climate activists, along with the desperate responses of some of the world's most prominent climate scientists, is preventing us from focusing on the survival requirements of the human enterprise. The environmental establishment continues to peddle the notion that we can solve the climate problem. We can't. We have failed to meet nature's deadline. In the next few years, this world will experience progressively more ominous and destabilizing changes. These will happen either incrementally -- or in sudden, abrupt jumps. Under either scenario, it seems inevitable that we will soon be confronted by water shortages, crop failures, increasing damages from extreme weather events, collapsing infrastructures, and, potentially, breakdowns in the democratic process itself. ----- Start with the climate activists, who are telling us only a partial truth.

Bird by bird

A third of avian species on land could disappear this century as a result of climate change

In more depressing bird news, researchers at my alma mater estimate that up to 30 percent of all land-dwelling bird species could be extinct by 2100 as a result of global climate change. The study, published this week in the journal Conservation Biology ($ub. req'd), modeled bird population responses to changes in vegetation for over 8,000 species and 60 scenarios, and is one of the first analyses of extinction rates to incorporate information from the recent IPCC reports. I think I'm going to go cry now.

Bali conference goes into second week

The latest from Bali: On Saturday, a draft text was produced suggesting that developed nations cut emissions between 25 and 40 percent below 1990 levels by 2020. The U.S. and Japanese delegations were displeased; by Monday, that target was reportedly dropped. Sen. John Kerry paid a visit to assure delegates, “I am convinced the politics of 2009 in the United States are going to be just night and day, different from where we have been before.” A faction of finance ministers and a troop of trade ministers gathered to discuss their specific interest in climate change issues. A Canadian environmental …

Fools on the Hill

Greed versus green on the energy bill

This post is by ClimateProgress guest blogger Bill Becker, Executive Director of the Presidential Climate Action Project. ----- As the new energy bill hit the Senate with a thud last week, we had to ask: Is it really so easy to stall vital public policy with tired old scare tactics? Last Friday, the answer was "yes." One of the potholes the bill has encountered is its $13 billion take-back from Big Oil. The bill proposes to repeal tax breaks given to the industry by the Republican-controlled Congress in 2004-2005 and to close some tax loopholes that allow oil companies to game the system when they report income from foreign oil and gas extraction. Predictably, the oil industry and the White House complained about a tax increase and warned of higher prices at the pump -- two time-tested themes to trigger knee-jerk opposition from the public. Let's break it down.

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