Thursday, March 22, 2007


Wednesday, March 21, 2007

To cool the planet

Is it really this easy? A couple billion per year?
Benford has a proposal that possesses the advantages of being both one of the simplest planet-cooling technologies so far suggested and being initially testable in a local context. He suggests suspension of tiny, harmless particles (sized at one-third of a micron) at about 80,000 feet up in the stratosphere. These particles could be composed of diatomaceous earth. "That's silicon dioxide, which is chemically inert, cheap as earth, and readily crushable to the size we want," Benford says. This could initially be tested, he says, over the Arctic, where warming is already considerable and where few human beings live. Arctic atmospheric circulation patterns would mostly confine the deployed particles around the North Pole. An initial experiment could occur north of 70 degrees latitude, over the Arctic Sea and outside national boundaries. "The fact that such an experiment is reversible is just as important as the fact that it's regional," says Benford.

Is Benford's proposal realistic? According to Ken Caldeira, a leading climate scientist at Stanford University and the Carnegie Institution's Department of Global Ecology, "It appears as if any small particle would do the trick in the necessary quantities. I've done a number of computer simulations of what the climate response would be of reflecting sunlight, and all of them indicate that it would work quite well." He adds, "I wouldn't look to these geoengineering schemes as part of normal policy response, but if bad things start to happen quickly, then people will demand something be done quickly."

Given that our social systems would crash without the economic growth that depends on the existing energy infrastructure that we have, Benford personally believes that governments can't be counted on to develop and deploy alternatives: "Anybody who thinks governments are suddenly going to leap into action is dreaming." Benford says that one of the advantages of his scheme is that it could be implemented unilaterally by private parties. "Applying these technologies in the Arctic zone or even over the whole planet would be so cheap that many private parties could do it on their own. That's really a dangerous idea because it suggests the primary actor in this drama will not be the nation-state anymore. You could do this for a hundred million bucks a year. You could do the whole planet for a couple of billion. That's amazingly cheap."

(HT: Randall Parker.)

It seems too good to be true, so what's the catch? I hope this option isn't being ignored simply because of some misplaced moral or aesthetic preference for a more penitent or passive method of reducing global warming.

Congressional job approval ratings only increased temporarily after the Democrats took power. Even the temporary increase never got approval much above 40%, though disapproval might have dipped below 50% a few times.
How globalized are the economies of the nations? About 10%.

Tuesday, March 20, 2007

Gloomy metastudies

Robin Hanson: "Medical studies are seriously biased by interested funders and by tolerance for sloppy methods. Here are four examples."
Options for countering the threat of al Qaeda in Pakistan. I like "Divide and conquer - support anti-al Qaeda factions inside Pakistan" the best, perhaps only because I don't know enough about Waziristan to be able to assign a low probability to its success.
I see that caffeine and cocoa have health benefits. I think it's time to indulge in a little confirmation bias, by which I mean Dr. Pepper.
Pell Grants have caused tuitions to rise. Of course, having a third-party payer drives up costs in just about all situations. Here's an anecdote from medicine; here's some data.

A picture is worth a thousand numbers.

The Social Security Coloring Book. (HT: Andrew Samwick.)

Stamp prices have grown just as fast as the CPI. (HT: Eric.)

The discretionary federal budget. (Does not include entitlements or interest payments on federal debt.) (HT: Dave W.)

Friday, March 09, 2007

Yes, we spend less time on the job than we did a century ago, and less time on housework, but a lot more time in school. The net result is negligble increase in leisure.
Based on available evidence, it seems that housekeeping involved about 56 hours a week in 1912. This fell to 52 hours a week by 1920 and stayed constant until 1965; it then declined again, dropping to 45 hours a week by 1975, and has been relatively constant since.

If we were willing to settle for the standards of nutrition, health and cleanliness that prevailed in 1900, much less labor would be required. But, as Betty Friedan has said in “The Feminine Mystique,” “housewifery expands to fill the time available.”

When you account for the much longer time in school, the more or less constant amount of time spent on housework, and make a few other adjustments, hours spent on purely enjoyable activities haven’t changed that much in the last century. Keynes may have been right that future generations will have a lot of time on their hands, but I wouldn’t bet on that happening anytime soon.

(HT: Greg Mankiw.) Read the academic paper here.

Thursday, March 08, 2007

Tolls can be inconvenient, but a new toll road is better than no new road:
Public-private toll road partnerships were rediscovered in France, Spain and Italy during the 1960s and '70s as the main method for building nationwide toll motorway systems.

The re-emergence of this model in the U.S. has been driven by a transportation system burdened with pork projects and funded by gas taxes that fail to keep up with construction and maintenance costs, let alone travel demand. From 1980 to 2000 highway travel increased 80% and the number of drivers rose by 30%, but highway capacity grew by just 2%. (Emphasis added.)

Progress against pork: better late than never. This sort of thing moves me a bit closer (but certainly not all the way---think judicial appointments, for starters) to the opinion that it was a good thing to take away the Republicans' Congressional majorities.

Monday, March 05, 2007

Here's a good explanation of Peter Shor's quantum factorization algorithm written for the layman. (HT: Geekpress.) Before I took a seminar class of Shor's three years ago, quantum computing seemed to me vaguely like magic. I'm always happy to see the real beauty and limitations of quantum computing more widely disseminated.