Which statement best explains the effect of high humidity on heat loss?

Which statement best explains the effect of high humidity on heat loss?

• A. Humidity increases heat loss by promoting evaporation
• B. Humidity has no effect on heat loss
• C. High humidity reduces heat loss by inhibiting evaporation
• D. Humidity only affects heat loss through convection

Answer: (C)

High humidity mainly hampers evaporative cooling. Sweat cools the body as it evaporates from the skin, and the rate of evaporation depends on the moisture level in the surrounding air. When the air is already saturated with water vapor, it can’t take up much more moisture from the skin, so evaporation slows down and less heat is removed. That’s why high humidity reduces heat loss by inhibiting evaporation. The other heat-loss pathways (conduction, convection, radiation) continue, but they don’t compensate as effectively as evaporation does, especially in heat and humidity.

High humidity mainly hampers evaporative cooling. Sweat cools the body as it evaporates from the skin, and the rate of evaporation depends on the moisture level in the surrounding air. When the air is already saturated with water vapor, it can’t take up much more moisture from the skin, so evaporation slows down and less heat is removed. That’s why high humidity reduces heat loss by inhibiting evaporation. The other heat-loss pathways (conduction, convection, radiation) continue, but they don’t compensate as effectively as evaporation does, especially in heat and humidity.