Steven Chu, Obama’s Energy Secretary has stated that if we paint our roofs and roads white, we will offset the effects of automobiles on global warming by 11 years. Can the Nobel Committee make him give his prize back?
First we have the idea of some geo-engineering experiment to block the sun's rays and now we have the proposal to paint everything white. These suggestions show a clear lack of understanding of basic thermodynamics, especially radiation heat transfer. And these guys are shaping our energy policy.
The earth has a property called “albedo”. Albedo is a measure of the reflectivity of an object. On a macro scale, the albedo of the earth is determined by the fact that our rock is covered 71% by water. The amount of surface area of the earth covered by roofs and roads is miniscule. Painting your roof white will not change the albedo of the earth. It will change the albedo of your house, but that may not be desireable, especially if you live in northen climes.
The earth is heated by the suns rays. These rays are in the UV and visible spectrum. They pass easily through the earth’s atmosphere and heat the ground/ocean. We know that hot objects give off radiation and some of that heat is radiated back into space, but that radiation is in the infrared range of the spectrum and these rays don’t penetrate the earth’s atmosphere all that well so most of the heat remains trapped under the blanket of air that makes up our atmosphere.
Think of your car on a summer day. I don’t care if your car is white or black, the sun's rays come through the windows and heat up the interior. The heat stays tapped inside the car because the hot car seat cannot radiate its excess heat back through the glass.
You can go paint your roof white if you want to. It might reduce your air conditioning bill by a few dollars. Me, I won’t waste the paint.
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3 comments:
Me, I'm gonna burn a big pile of tires out back to increase my carbon footprint as often as possible to try and kick start global warming instead of the cooling we've been getting. Might reduce my heating bill in the winter :-)
Have to run A/C in Texas most of the year even if you coul change avg temps by a degree or two either way. White roof wouldn't be much different than my au naturale galvanized steel roofs, methinks, as to AC bills.
People get stupider and stupider with each successive generation. The old adage "Stupid is as stupid does" has never been truer.
They should all paint the tops of their heads white, so that we all know which ones are the moonbats and which of us are sane.
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