After a clear, calm night over damp farmland, a shallow layer of fog appears around sunrise. What type of fog is this?

Giải thích

Radiation fog forms on clear, nearly calm nights when the ground radiates its heat away, chills the moist air just above it to the dew point, and leaves a shallow ground fog that is usually thickest near sunrise. It typically burns off within a few hours after the sun warms the surface. Advection fog requires horizontal movement of warm moist air over a cold surface, upslope fog requires terrain and wind, and steam fog requires a warm water surface under cold air.