climate

All posts tagged climate

Book review: Global Catastrophic Risks by Nick Bostrom, and Milan Cirkovic.
This is a relatively comprehensive collection of thoughtful essays about the risks of a major catastrophe (mainly those that would kill a billion or more people).
Probably the most important chapter is the one on risks associated with AI, since few people attempting to create an AI seem to understand the possibilities it describes. It makes some implausible claims about the speed with which an AI could take over the world, but the argument they are used to support only requires that a first-mover advantage be important, and that is only weakly dependent on assumptions about that speed with which AI will improve.
The risks of a large fraction of humanity being killed by a super-volcano is apparently higher than the risk from asteroids, but volcanoes have more of a limit on their maximum size, so they appear to pose less risk of human extinction.
The risks of asteroids and comets can’t be handled as well as I thought by early detection, because some dark comets can’t be detected with current technology until it’s way too late. It seems we ought to start thinking about better detection systems, which would probably require large improvements in the cost-effectiveness of space-based telescopes or other sensors.
Many of the volcano and asteroid deaths would be due to crop failures from cold weather. Since mid-ocean temperatures are more stable that land temperatures, ocean based aquaculture would help mitigate this risk.
The climate change chapter seems much more objective and credible than what I’ve previously read on the subject, but is technical enough that it won’t be widely read, and it won’t satisfy anyone who is looking for arguments to justify their favorite policy. The best part is a list of possible instabilities which appear unlikely but which aren’t understood well enough to evaluate with any confidence.
The chapter on plagues mentions one surprising risk – better sanitation made polio more dangerous by altering the age at which it infected people. If I’d written the chapter, I’d have mentioned Ewald’s analysis of how human behavior influences the evolution of strains which are more or less virulent.
There’s good news about nuclear proliferation which has been under-reported – a fair number of countries have abandoned nuclear weapons programs, and a few have given up nuclear weapons. So if there’s any trend, it’s toward fewer countries trying to build them, and a stable number of countries possessing them. The bad news is we don’t know whether nanotechnology will change that by drastically reducing the effort needed to build them.
The chapter on totalitarianism discusses some uncomfortable tradeoffs between the benefits of some sort of world government and the harm that such government might cause. One interesting claim:

totalitarian regimes are less likely to foresee disasters, but are in some ways better-equipped to deal with disasters that they take seriously.

Sen. John Barrasso (R-WY) has introduced a bill to create prizes for carbon sequestration:

This is how it would work. There would be four different levels of prizes. The first level award would go to the public or private entity that could first demonstrate a design for a successful technology that could remove and permanently sequester greenhouse gases. Second, there would be a prize for a lab scale demonstration project of the technology that accomplishes the same thing. Third, there would be an award for demonstrating the technology to remove and permanently sequester greenhouse gases that is operational at a larger, working model scale. Finally, there would be an award for whoever could demonstrate the technology to remove and permanently sequester greenhouse gases on a commercially viable scale.

It sounds like many important details would be decided by a federal commission. The prizes could have many of the promises and drawbacks of Virgin Earth Challenge.
The first three levels of the prizes appear to create incentives to create designs with little regard for commercial feasibility. If those prizes are large, they might end up rewarding technologies that are too expensive to be worth using. Small prizes might have little trouble with this due to inventors not wanting to spend much money to win the prizes, but I’d still have concerns about inventors paying little attention to reliability and maintenance costs. The fourth level appears more promising.
Bureaucrats are likely to put more effort into clarifying prize rules that the Virgin Earth group did. But it’s unclear whether any approaches that a government agency is likely to recommend will do a decent job of translating the “commercially viable” goal into a clear enough set of rules that inventors will be able to predict how the prizes will be awarded.
My advice for the commission, should it be created, is that it tie the prizes to actual amounts of carbon removed from the atmosphere over some pre-specified period, or to estimates of those amounts derived from a prediction market.
(HT Jim Manzi).

Cool It

Book review: Cool It: The Skeptical Environmentalist’s Guide to Global Warming by Bjørn Lomborg.
This book eloquently counters many popular myths about how much harm global warming is likely to cause, but is sufficiently partisan and one-sided that it will do more to polarize the debate than to resolve disagreements. Many of his criticisms of the alarmists are correct. Reading this book in combination with writings of his opponents will give you a much better perspective than reading only one side of this debate.
Selective reporting gives the impression that global warming is causing more deaths, but Lomborg reports that warming will cause reduced deaths for the foreseeable future, mainly through reduced cold-related cardiovascular deaths. He claims warming won’t cause a net increase in deaths until at least 2200, but I expect that uncertainty about medical innovation makes predictions more than a few decades ahead not credible. Even for the next few decades, he exaggerates the evidence. What he calls “The first complete survey for the world” covers the entire world, but only tries to model the effects of the 6 types of disease for which global information is available, and its authors clearly deny knowing whether other diseases have important effects. Lomborg claims there will be 1.4 million fewer deaths in 2050 due to global warming, but he seems to get that number from the effects of only two disease types, whereas the paper he cites predicts 849252 fewer deaths from 6 disease types.
He is often too dismissive of the possibility of technological improvements. For instance, he claims that sticking to Kyoto commitments through the 21st century “would get ever harder”, yet I can imagine a variety of ways it could get easier. He mentions specific dollar costs for complying with Kyoto for a century without hinting at the large uncertainties in those guesses.
In one place he analyzes Kyoto as if it were a foreign aid program, and says that it would do 16 cents of good in developing countries for every dollar spent. I assume he considers this an argument against Kyoto. Since 16 cents might help a person in a developing country more than a dollar helps a person in a developed country, and there is some reason to suspect that few large aid programs are more than 16 percent efficient, it could easily be considered a weak argument for Kyoto.
Sometimes he’s blatantly careless, such as when he talks about “reducing [hurricane] damage by almost 500 percent”.
He appropriately criticizes the Stern report’s use of a suspiciously low discount rate (which has major implications for how much we should do now), but he doesn’t provide a clear explanation of that issue, nor does he say what his preferred model uses (a review on Salon says it uses a 6 percent discount rate, which I suspect only makes sense if we assume a higher economic growth rate than most experts expect).

While there is much debate about whether we should respond to global warming by taxing CO2 emissions at $2 per ton or $140 per ton, there are countries with policies that are roughly equivalent to rewarding CO2 emissions at levels that appear to exceed $100 per ton.
I’m referring to gasoline pricing rules that keep gas prices at the local consumer level way below the global market price. Venezuela is a dramatic example, China has prices that are modestly below the market price, but that applies to an important fraction of the world’s gas use, and last I heard Iran and Iraq were practically giving away whatever gas became available to their consumers (it’s sad that Iraq was invaded by a government that didn’t think freer markets would help Iraq). These policies would be wasteful even if CO2 emissions were good (e.g. due to causing long lines to get gas).
Even if those low prices are implemented in a way that helps the poor in those countries, it causes nontrivial increases in gas demand which drive up gas prices in the rest of the world (at least in the short run; the long run price changes depend on the cost of finding new oil).
People who care enough about global warming to make modest efforts to slow it should put pressure on these countries to charge market prices for gas. In addition to traditional techniques, one obvious response is to exploit the inherent instability of these price differentials by giving as much aid and protection as is practical to the heroic businessmen who smuggle gas from low price regions to regions where marker prices prevail. If governments of Europe and the U.S. cared enough about global warming, they could probably enable enough smuggling to measurably reduce the waste of gas in many smaller countries. But that would probably still leave significant waste in China, and I’m not sure what can be done about that.

One way to find evidence concerning whether a politicized theory is being exaggerated or being stated overconfidently is to look at how experts from a very different worldview thought about the theory. I had been under the impression that theories about global warming were recent enough that it was hard to find people who studied it without being subject to biases connected with recent fads in environmental politics.
I now see that Arrhenius predicted in 1896 that human activity would cause global warming, and estimated a sensitivity of world temperature to CO2 levels that differ from current estimates by about a factor of 2. The uncertainty in current estimates is large enough that they disagree with Arrhenius by a surprisingly small amount. This increases my confidence in that part of global warming theory.
Arrhenius disagreed with modern theorists about how fast CO2 level would rise (he thought it would take 3000 years to rise 50% or to double, depending on whether you believe Nature or Wikipedia), and about whether warming is good. That slightly weakens my confidence in forecasts of CO2 levels and of harm from warming (although as a Swede Arrhenius might have overweighted the benefits of warming in arctic regions).

The Virgin Earth Challenge would be a great idea if we could count on it being awarded for a solution that resembles the headlines it’s been getting (e.g. $25M Bounty Offered for Global Warming Fix).
But the history of such prizes suggests that even for simple goals, describing the terms of a prize so that inventors can predict what will qualify for the award is nontrivial (e.g. see the longitude prize, where the winner appeared to have clearly met the conditions specified, yet wasn’t awarded the prize for 12 years because the solution didn’t meet the preconceptions of the board that judged it).
Anyone who looks past the media coverage and finds the terms of the challenge will see that the criteria are intended to be a good deal more complex than those of the longitude prize, that there’s plenty of ambiguity in them (although it’s possible they plan to make them clearer later), and that the panel of judges could be considered to be less impartial than the ideal one might hope for.
The criterion of “commercial viability” tends to suggest that a solution that required additional charitable donations to implement might be rejected even if there were donors who thought it worthy of funding, yet I doubt that’s consistent with the intent behind the prize. This ambiguity looks like simple carelessness.
The criterion of “harmful effects and/or other incidental consequences of the solution” represents a more disturbing ambiguity. Suppose I create nanobots which spread throughout the biosphere and sequester CO2 in a manner that offends some environmentalists’ feelings that the biosphere ought to be left in its natural state, but otherwise does no harm. How would these feelings be factored into the decision about whether to award the prize? Not to mention minor ambiguities such as whether making a coal worker’s job obsolete or reducing crop yields due to reduced atmospheric CO2 counts as a harmful effect.
I invite everyone who thinks Branson and Gore are serious about paying out the prize to contact them and ask that they clarify their criteria.

Nick Szabo has a very good post on global warming.
I have one complaint: he says “acid rain in the 1970s and 80s was a scare almost as big global warming is today”. I remember the acid rain concerns of the 1970s well enough to know that this is a good deal of an exaggeration. Acid rain alarmists said a lot about the potential harm to forests and statues, but to the extent they talked about measurable harm to people, it was a good deal vaguer than with global warming, and if it could have been quantified it would probably have implied at least an order of magnitude less measurable harm to people than what mainstream academics are suggesting global warming could cause.

Book review: An Inconvenient Truth: The Planetary Emergency of Global Warming and What We Can Do About It by Al Gore
I read An Inconvenient Truth in book form rather than watching the movie because I’m generally suspicious of attempts to convey serious arguments via film, and expected that the book version would have better references to the sources of his claims. Alas, this is merely a movie copied to paper, and his idea of a technical reference is a label such as “source: science magazine”.
This may be more scholarly than what a typical politician would produce, but it’s poor scholarship compared to what I’d expect from a typical college professor, even allowing for the goal of reaching a wide audience by keeping it simple.
The book is full of exaggerations and misleading impressions (but is usually not explicit enough to be clearly false). It is hard to say whether the book is helping by offsetting myths from the other extreme or whether it is adding to the confusion. Gore does deserve some credit for bringing more attention to a fairly serious problem.
Much of the book is pictures showing examples of climate changes, which don’t by themselves say whether we’ve experienced anything more than normal fluctuations. The movie may have reached people who thought climates were more stable than that, but I doubt the book will.
His main attempt to show evidence that CO2 emissions cause warming is a graph showing CO2 levels and temperature over the last 600,000 years. It sure looks like there’s a strong correlation. But my crude attempts at comparing the timing of the changes suggest that temperature changes precede CO2 changes more often than they follow them. I can imagine ways that the correlation could be caused by temperature changes causing changes in CO2 levels. I don’t see how a non-expert can tell what this correlation implies except by relying on authority (experts seem to think the causation works in both directions).
So that leaves him with only appeals to authority to back up his claims. He’s more credible there. His claim of a scientific consensus is approximately right. He lists the “percentage of articles in doubt as to the cause of global warming: 0%”. The paper he’s apparently referencing is responsible enough to use words such as “likely” rather than claiming an absence of doubt. Peter Norvig‘s analysis of some of those papers concludes at least 4 of those papers expressed doubt. But that difference is probably too subtle to matter to the people this book is targeting.
Gore is quick to blame big oil for the popular press’s false impressions of scientific controversy. The possibility that controversy sells stories appears to be at least as strong an explanation, but blaming the people Gore’s trying to convince would be rather inconvenient.
Pages 183 to 196 appear designed to create fears that sea levels could rise 18 to 20 feet suddenly and unpredictably. He doesn’t say anything about how fast experts think this might happen (which seems to be over many decades). The hints he gives are the mention of an ice shelf than unexpectedly broke up in 35 days, and some maps Greenland which appear to suggest the ice there could vanish in the next decade. The difference between an expected sea level rise over many decades and an unexpected rise over less than a decade makes a big difference in how well people could adapt to it. (The mass migrations in China recently demonstrate the feasibility of adapting to sea level changes in a decade or two). Gore appears to be contributing to fears of changes that are way outside the expert consensus.
Gore underestimates human ability to adapt to climate change (much as those on the other extreme underestimate human ability to invent affordable ways to reduce carbon emissions). For example, he implies that quick efforts to mitigate global warming are the only way to deal with the risks of drinking water shortages. But I see signs that cheaper desalinization is a more promising approach.
His graph on page 276 of “U.S. renewable energy future” is strange. Renewability has a weak connection to global warming solutions, but the possibility that nuclear power might be desirable seems too inconvenient to him. His forecast for biomass looks too optimistic, his forecast for solar after 2020 looks too pessimistic, and his forecast for wind shows strange fluctuations.
Gore repeats the myth that frogs won’t jump out of water that’s slowly brought to a boil, and claims that sometimes people make the same mistake. “Sometimes” is too uninformative to refute, but the most relevant research that I can think of suggests that at least political experts are biased toward sounding alarms too often.
He claims it’s “absolutely indisputable” that global warming is a “planetary emergency”. Yet nothing he says implies that stopping global warming is as urgent as reducing poverty, war, or disease.
Ph.D. economists seem fairly confident that the effects of global warming will be small.
There are substantial disputes among experts about how much of the global warming problem we should try to solve now (see Hal Varian’s comments, Tyler Cowen’s comments and Arnold Kling’s comments). But you won’t find any hint of that controversy in An Inconvenient Truth (in part because it’s hard to describe in ways that laymen can understand).
Gore recommends doing many things to slow down global warming a bit (but may leave many with the impression that his plans would do more than that – if it were an emergency as he says, wouldn’t he recommend more?).
Some of these steps are clearly good even if their effects on the climate are trivial.
For some (recycling and locally grown food) I’ve seen conflicting claims and can’t tell whether objective analyses exist.
Some are misleading. He claims a “fuel-cell vehicle (FCV) that uses pure hydrogen produces no pollutants”, which would be true if we had a convenient source of pure hydrogen. But on this planet, hydrogen requires energy to create, and only acts as a battery, so FCVs cause pollution if energy production causes pollution.
I recommend Ron Baily’s review for additional criticisms.
Disclosure: I own stocks in oil companies and in a company that serves the photovoltaic industry.

Book review: The Undercover Economist: Exposing Why the Rich Are Rich, the Poor Are Poor–and Why You Can Never Buy a Decent Used Car! by Tim Harford
This book does an excellent job of describing economics in a way that laymen can understand, although experts won’t find much that is new in it.
Harford’s description of price discrimination is the best I’ve seen, and the first to describe how to tell the extent to which an instance of price discrimination has good effects (the extent to which it expands the number of sales).
His arguments that globalization reduces pollution are impressive for most types of pollution, but for carbon dioxide emissions I’m very disappointed. He hopes that energy use has peaked in the richest countries because he’s failed to imagine what will cause enough increased demand to offset increases in efficiency. For those of modest imagination, I suggest thinking about more realistic virtual reality (I want my Holodeck), personal robots, and increased air conditioning due to people moving to bigger houses in warmer climates. For those with more imagination, add in spacecraft and utility fog.
Some small complaints:
He refers to Howard Schultz as the owner of Starbucks, but he only owns about 2 percent of Starbucks’ stock.
His comment that Amazon stock price dropped below its IPO price fails to adjust for stock splits – a share bought at $18 in 1997 would have become 12 shares worth $8 each in the summer of 2001.
His claim that “Google is the living proof that moving first counts for nothing on the Internet” is a big exaggeration. It’s quite possible that Google success was primarily due to being the first to reach some key threshold of quality, and that many small competitors have matched its quality without taking measurable business away from it.

A recent report says that switching from a meat-heavy diet to a vegetarian diet is as valuable for reducing greenhouse-gas emissions as switching to driving the right car. And that if you eat fish, switching from large fish to things like sardines and anchovies makes a big difference.
I’m unsure whether to believe the magnitudes of the differences, but the general idea appears right.