"He asks where the reflected heat from white roads would go. The answer, of course, is that the UV and visible light components of solar radiation would not be absorbed into the road to be turned in to heat but rather returned to outer space"
Not really. Energy form the sun enters the atmosphere as shortwave radiation. Soon as it hits something solid, regardless of the color, it changes to long wave radiation - essentially heat. Whether the heat is absorbed by a black road or roof - and then slowly released into the atmosphere at night, or hits a white surface and the majority of the heat is absorbed by the atmosphere, all the long wave/heat energy ends up in the atmosphere, where it warms that atmoshpere.
This is just another one of the "Stuck on Stupid" ideas that sounds good but shows a complete non-understanding of atmospheric physics.
And can you imagine white highways here in the Great White North in the middle of winter ? What road you say, where the hell is it ??
Now that would be fun driving. Think Saskatchewan in a winter storm
