Sullivan starts a thread on white roofs. This Duke University prof confuses me by arguing that white roofs are so good at cooling that in the winter (anything can be argued true when you can point to a somewhat-related scientific study!) you'll have to provide extra heat to offset the lack of sun heating the normally black roof. This extra heating is greater than (the article and Dr. Chameides argue) the decrease in cooling needed during the summer, therefore white roofs are a plague on the world and cause increased carbon dioxide production.
I'm no NOAA scientist running calculations and I have to give them credit, but something here seems really fishy to me. And I think the problem is that they've de-regionalized a sustainability solution. On a global scale, they argue (and admit the limitation of the argument) that white roofs are a net negative. But they also concede that air conditioning isn't available in many places, nor are Energy Star appliances.
This leads me back to what I've been arguing for quite some time: in order for sustainability to work it needs to be regionalized. Although water conservation in general is a good idea (or rather wasting water is a bad idea), it doesn't make sense for an architect designing a building in Missouri to put in low-flow toilets when that architect could save money on normal toilets and use that money instead on better wall and attic insulation. In New Mexico, it makes more sense to focus on solar installation and water conservation. In Minnesota focus on better insulation for homes.
Look, sustainability is important, and as TPI once smartly pointed out: its easy and the technology is readily available to decrease our carbon consumption through efficiency gains rather than futuristic clean energy concepts like fusion. But sustainability cannot be applied with a broad brush. Especially when climates vary, societal pressures vary, etc.
So while white roofs put on every roof on the planet might not be a net gain...its still a really good idea for a lot of areas.