Wednesday, March 14, 2007

An interesting proposal...

...to reduce the impact of solar emissions on global temperatures might be to simply avoid the use of dark materials in building construction. No kidding. New Scientist magazine h(H/T David Strom)as an article that makes the claim that if builders were to simply use high reflectivity materials instead of low reflectivity materials, the amount of heat retained in the lower atmosphere could be reduced and warming effects countered. On the flip side, if we accepted the "truth" of the late 1970s and global cooling was a concern, we could all reshingle our roofs with black shingles and get some relief from 30 below.

Now the reality is that it's not quite that simple; it's not for no reason that climatologists have failed to produce models that match historic data. But that said, it is well known that cities and forests are measurably warmer than their surroundings, ceterus parabus, and a major reason for this is because they're more or less darker. This also comes as no surprise to anyone who has ever painted a room lighter or darker and found that the lightbulb was too much, or too little. Charts for lighting designers include the reflectivity of various surfaces--white paint is about 0.8, and dark surfaces are about 0.3--which is, according to the article, about the mean for the earth.

This also suggests a secondary way of controlling at least local climate; use more durable concrete surfaces for roads when possible instead of asphalt. Like David, I'll be waiting for environmentalists to step up to the plate and concede that Kyoto is a failure, but sensible building guides could be a resounding--and far less costly--success.

4 comments:

Shawn said...

1: you're not allowed to use random ellipsis, especially at the beginning of a post, without my permission.

2: as a person with a flat roof house, I've been strongly considering playing with the idea of painting my roof white. apparently, there's a "viscoelastic" paint that's particularly useful for the job.

Shawn said...

1: you're not allowed to use random ellipsis, especially at the beginning of a post, without my permission.

2: as a person with a flat roof house, I've been strongly considering playing with the idea of painting my roof white. apparently, there's a "viscoelastic" paint that's particularly useful for the job.

Shawn said...

1: you're not allowed to use random ellipsis, especially at the beginning of a post, without my permission.

2: as a person with a flat roof house, I've been strongly considering playing with the idea of painting my roof white. apparently, there's a "viscoelastic" paint that's particularly useful for the job.

Bike Bubba said...

Gosh, you should have commented on this earlier, as I've been using it for a while. :^)

And well said--I've actually been partial to light colored shingles for years due to the heat that dark shingles put into the home--really since I was a kid, believe it or not. And as a bicyclist, I've long preferred concrete to blacktop for this reason--and also because it's not as slick on a wet day as well.

But why anyone would put a flat roof on a home where it rains or snows is beyond me.... :^)