Dew formation and atmospheric conditions

Dew forms when the Earth's surface cools by radiation on clear nights, causing the air near the ground to cool below the dew point temperature, allowing water vapor to condense. On cloudy nights, clouds act as a blanket and absorb the infrared radiation emitted from the Earth's surface, preventing rapid cooling. This keeps the ground temperature relatively warm, so the air near the surface does not cool sufficiently to reach the dew point, and dew does not form. Option b is incorrect because while clouds reflect some radiation, absorption is the primary mechanism. Options c and d do not correctly explain the phenomenon. > Clouds ABSORB Earth's radiation on cloudy nights, preventing surface cooling needed for dew formation. Answer: (a).