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I suggest painting the roofs of buildings white, or use other light reflective colours and or materials.




I suggest painting the roofs of buildings white, or use other light reflective colours and or materials.

Researchers at Lawrence Berkeley National Laboratory. "For the northern hemisphere summer, they found that increasing the reflectivity of roof and pavement materials in cities with a population greater than 1 million would achieve a one-time offset of 57 gigatons (1gigaton equals 1 billion metric tons) of CO2 emissions (31 Gt from roofs and 26 Gt from pavements). That's double the worldwide CO2 emissions in 2006 of 28 gigatons." Cool Roofs Can Offset Carbon Dioxide Emissions and Mitigate Global Warming (ScienceDaily July 20, 2010)

A rough estimate of the costs of painting urban surfaces and structures white has been presented in the study Geoengineering the climate by the Royal Society:

"Assuming a re-painting period of once every ten years, combined paint and manpower costs would be of the order of $0.3/m2/yr, although this would likely vary greatly from country to country. On this basis the overall cost of a ‘white roof method’ covering an area of 1% of the land surface (about 1012 m2) would be about $300 billion/yr, making this one of the least effective and most expensive methods considered." p. 25

But if the structures has to been painted anyway, why not paint them white?

The question is what would be the best way to achieve this. I suggest two options that could be used separately or as a combination:

1)      it could be mandatory in building codes,

2)      education


In the second option the additional benefit of diminished need for air conditioning should be emphasized. 


Category of the action

Building efficiency, Social Action

What actions do you propose?

Who will take these actions?

Where will these actions be taken?

How much will emissions be reduced or sequestered vs. business as usual levels?

What are other key benefits?

What are the proposal’s costs?

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