5 ms·

But given that dark colors also radiate heat, wouldn't the white be better year round anyways?

• jarek 16y ago
  Dark coloured surfaces will tend to absorb more heat. You want that in the winter to help melt snow and ice.
  • brudgers 16y ago
    When there is snow and ice on the road the surface will is light colored (white or grey).
  • iwwr 16y ago
    Dark surfaces radiate the minimum amount of heat, though. A perfectly black body will absorb all incoming radiation and re-emit it back by a Boltzmann distribution (according to its temperature). Less than perfect surfaces would reflect some the incident light/heat; if they reflect at the same constant or regular angle, we recognize it as 'shiny', while if it's a random angle, our eyes recognize it as matte/solid white.
    • jarek 16y ago
      While you are correct, in the case of dark pavement with patches of snow lying on top, conduction will be a far more prominent transfer mode than radiation. (Although neither will be really large, and I think the blinding effect from a light pavement would be a more important issue here.)
  • mauriciob 16y ago
    Except it won't absorb anything if the snow reflects all of the light. It makes sense to absorb heat when there is little or no snow, but it doesn't at all when snow covers all of the surface.