UPDATE: have a look at Clinton’s house below. Yep, that’s the big plan. Paint your roofs white. From the Atlantic:
I have no problem with saving energy, especially in the summer when power drain is excessive due to A/C load. California now requires most flat-roofed buildings to be white. As a testament to the potential cash savings, Walmart has installed white roofs on 75% of its stores in the United States. Roofs comprise over 20% of urban surface, so while painting them all white in a city, there’s still a lot of asphalt.
But paint roofs white has a downside as well as an upside. It depends on where you live. If you live in a mostly warm climate, say Miami or Phoenix, you’ll realize energy savings. But if you live in Minot,ND or International Falls, MN your white roof will not absorb as much sunlight in winter, thus requiring more energy for heating.
The point is, painting roofs white natiowide, willy nilly, without regard to the local climate, average temperatures, the number of days of sunshine etc. won’t be a full solution.
An idea like Cool Angle, might work, but is far more involved than a paint job.
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UPDATE: Reader John provides this image link to the former president’s home. Goose, gander, and all that. We look forward to seeing Bill lead the way.
Source: http://www.zillow.com/howto/FamousPresidentsHomes.htm
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Andy Adkins says:
July 20, 2011 at 2:20 pm
Correct me if I am wrong…
To be honest I’m not entirely clear on what you’re saying. If you’re arguing that the use of white paint will simply shift heat energy to another part of the planet then I’ll say you’re wrong.
The point of white paint is that something is white when it reflects in all wavelengths of the visible part of the spectrum. On the other hand something is black when it absorbs energy in all visible wavelengths. A large proportion of sunlight arrives in the visible range so a white surface will reflect much more energy than a black surface and a black surface will absorb much more energy.
Locally this means white paint makes a difference because the energy is batted out somewhere else, but it also affects global radiation budget and here’s why: Whether the surface is white or black (or whatever colour), the energy coming into it must be released at some stage. If it has been reflected the energy will retain the same wavelength – in this case it will remain in the visible range, also known as shortwave radiation – whereas if the energy is absorbed it will emit at a wavelength proportional to the temperature of the object. Assuming the object is not as hot as the surface of the Sun energy will emit from it in longer wavelengths and is known as longwave radiation.
White paint compared to black paint changes the wavelength profile of energy going up from the surface to include a greater proportion in shortwave bands. The atmosphere is mostly transparent to shortwave radiation but is quite opaque to longwave radiation, so shortwave is more likely to escape out to space. Therefore using white paint versus black, or any other plain colour, would actually reduce the global radiation budget.
Paul are you really saying that White paint will permanently change longwave radiation into shortwave radiation that can move unaltered by the properties of air (movement, density,etc)through 50km of atmosphere. Your proposition may work in lab experiments, but it just seems like nonsense every time I bring my kite outside.
Andy Adkins says:
July 21, 2011 at 7:34 am
Paul are you really saying that White paint will permanently change longwave radiation into shortwave radiation that can move unaltered by the properties of air (movement, density,etc)through 50km of atmosphere. Your proposition may work in lab experiments, but it just seems like nonsense every time I bring my kite outside.
No, solar energy arrives at the Earth as shortwave radiation and will either be absorbed or reflected by the objects it hits. If it is absorbed by the surface it will be re-emitted at some point as longwave radiation; if it is reflected by the surface it will remain shortwave. A white surface will reflect more than it absorbs so more energy will remain shortwave.
The atmosphere as a whole is more transparent to shortwave than longwave so having a greater proportion of energy coming off the surface as shortwave will mean more energy lost to space and less going back to the surface.
FYI-
Roofs in the North are usually covered with white snow during the winter.
As I was saying earlier, to reduce global warming, removal of snow in the north on streets and roofs must be stopped as this is not a natural (green) activity. The paint is not going to work as it does not have the reflective properties of snow. It does seem like minimum temps. are rising in the winter months in the NH due to snow removal, especially in densely populated areas like Holland.
http://www.letterdash.com/HenryP/henrys-pool-table-on-global-warming
http://www.letterdash.com/HenryP/the-weather-in-holland
My calibrated eyeball tells me that Mr. Clinton has as much blacktop square footage as he does roof square footage. Perhaps he’ll paint it white or tear it up and use a white gravel base of some sort, instead of that evil oil topped park.