Which of the following processes would lower the relative humidity of a parcel of air?
A) The air moves over a lake where water is evaporating.
B) The air is heated, and no water enters or leaves the system.
C) The air cools, and no water enters or leaves.
D) Dust blows into the air, but no other changes occur.

Question

Quizplus · Accepted Answer

When air is heated, its ability to hold water vapor increases, which means the amount of moisture in the air remains the same, but the relative humidity decreases. Option A would increase the relative humidity as the air picks up more water vapor through evaporation. Option C would increase the relative humidity as the cooler air is unable to hold as much water vapor. Option D does not affect the moisture content of the air, so the relative humidity remains the same.

Which of the Following Processes Would Lower the Relative Humidity