Which statement explains why bridges ice before roads?

Which statement explains why bridges ice before roads?

• A. Bridges have less sun exposure
• B. Cold air circulates above and below the bridge
• C. Bridge paint prevents ice formation
• D. Roads are salted earlier

Answer: (B)

When temperatures drop, surfaces freeze when they lose heat to the surrounding air. A bridge deck loses heat to cold air flowing both above and below it, so it cools and freezes faster than a road sitting on the ground. The ground beneath roads and the sun’s warmth can keep road surfaces a bit warmer for longer, delaying icing. The idea that cold air circulating around and under a bridge explains why ice appears there first. Other reasons like sun exposure, paint, or salting timing don’t consistently account for the quicker icing of bridges.

When temperatures drop, surfaces freeze when they lose heat to the surrounding air. A bridge deck loses heat to cold air flowing both above and below it, so it cools and freezes faster than a road sitting on the ground. The ground beneath roads and the sun’s warmth can keep road surfaces a bit warmer for longer, delaying icing. The idea that cold air circulating around and under a bridge explains why ice appears there first. Other reasons like sun exposure, paint, or salting timing don’t consistently account for the quicker icing of bridges.