Hey there, time traveller!
This article was published 15/7/2009 (4358 days ago), so information in it may no longer be current.
President Barack Obama's energy secretary, Steven Chu, recently spoke of the benefit of whitening cities to reduce greenhouse gas emissions. He cited research that found if 63 per cent of roofs in 100 large cities were whitened it would be equivalent to taking all the world's billion cars off the road for 10 years.
White reflects light back to the atmosphere where it passes through the canopy of greenhouse gases, taking heat energy with it.
Cool roof products for commercial and residential use are widely available. You could also paint your shingles white. That's what Jay Beeson of Austin, Texas, did. On a CBS news segment, Beeson described his roommates' reaction to his rooftop paint job.
"They were like 'wow dude, it's nice and cool in here now!'"
Of course, that's Texas. What about white roofs in Winnipeg? Nobody can argue against the summer benefit. Besides reflecting sunlight back to space, reflective roofs would let air conditioners enjoy more idle time. But would our winter wipe out summer gains? Hashem Akbari, senior scientist at the Lawrence Berkeley National Laboratory and author of the research Obama's environment man cited, says Winnipeg would still get a net benefit in spite of our winter.
"A white roof, no matter where it is, reflects incoming solar radiation and hence slows the rate of global warming." Akbari says anyone who uses energy to cool and heat a building will save money with a white roof.
Since Canada appears to be waiting for U.S. leadership in the global warming fight, surely now our leaders -- federal, provincial, municipal -- can start encouraging Canadian business and citizenry to lighten our skyward facades. Picture Stephen Harper, Gary Doer, and Sam Katz on stage together, arm-in-arm, excitedly sharing their white roof strategy to fatten our wallets and save our climate. A lovely dream, that. Unfortunately our leaders seem to say as little as possible about global warming during waking hours.
Prof. Danny Blair thinks politicians see a risk in talking to voters about solutions. Blair, who teaches atmospheric science and climate change at the University of Winnipeg, also finds time to dream. "My dream is to have somebody at the federal level, or even at the municipal or provincial level, with the courage to say the things that need to be said."
If Mayor Katz held a news conference and told us we should strive to cool our rooftops, would he suffer politically? If he told us to inflate our tires and air-dry our clothes, might he be impeached?
It could be that politicians fear the wrath of the small but outspoken forces still promoting the idea that humans aren't causing global warming. In case that's it, here is some political cover from David Phillips, the senior climatologist with Environment Canada.
"You can't explain what's happened by simply natural forces. Sun spots, volcanism, orbital changes, all those physical reasons that have changed climate in the eons of the past cannot explain what we've seen. Now, if you factor in the human component -- CO2 loading and land-use changes -- eureka! You get a perfect pattern."
We're causing global warming. It's now up to us to do what we must do and demand more from our leaders. Edmund Burke said, "Nobody made a greater mistake than he who did nothing because he could do only a little."
Whitening rooftops is an opportunity for us to do a lot.
Sean Ledwich is a Red River College student majoring in journalism.