Final answer:
The Earth's temperature would decrease if its surface turned white because less solar insolation would be absorbed due to the higher reflectivity of the white surface.
Step-by-step explanation:
If the surface of the Earth were to suddenly turn pure white like fresh snow, the temperature of the planet would Decrease; Less insolation would be absorbed. This is due to the higher albedo of the white surface, which would reflect more of the Sun's radiation back into space rather than absorbing it. Absorbed sunlight or insolation is what warms the Earth's land, water, and atmosphere. Since a white surface would reflect most of this energy, less warming would occur compared to darker surfaces which absorb more insolation.