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Deflecting sunlight in orbit is interesting.

Regarding deflecting light, for a long time white roofs have been pushed as a reflection mechanism[1] to deflect and lower energy costs thus reducing emissions. Though white roofs may actually increase warning in the way it reflects light onto other particles and doesn't help block it from coming into the atmosphere. Solar roofs capture it better and may be a better emissions lowering tool.

Seems like a better idea to do it from space, unless of course it goes too far and is difficult to control.

[1] https://www.theguardian.com/environment/2011/oct/27/white-ro...




This seems really viable.

Deflecting is still better than absorbing on the roof top, since roof top means 100% warmth absorption and deflection always less than 100%, probably only a fraction of that.


Your assuming that the atmosphere is more transparent to infrared (from a hot roof) then optical ranges (from a white roof).


No?

The atmosphere is more transparent to sunlight than to IR, thanks to greenhouse gases.

That's why absorbent roofs heat the Earth more than reflective roofs.


No. As an a example, I'm assuming that hot roofs absorb 70% of the incoming energy and reflect 30%, where reflectig roofs absorb 10% and reflect 90%. These numbers can be a bit different, but I'm pretty sure that hot roofs absorb a multiple of energy compared to reflecting roofs. Makes sense?




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