answersLogoWhite

0

I am assuming that the questioner is asking why humidity increases when it is hot. The answer to this is actually kind of complicated and involves a lot of conditions. Generally, though, warmer air can hold more water vapor than cooler air, so provided that there is a source of free water to evaporate and an energy source to drive that evaporation, warmer air will have more moisture content than cooler air. the complication arises due to how humidity is typically measured and expressed. The most common way to actually measure and express humdity is relative humdity, which can be thought of as the ratio of how much water vapor is in the air, to how much it can actually hold. Since the holding capacity increases with temperature, it is quite possible that the actual amount of water vapor in the air can increase, while the relative humidity actually goes down. This is fairly common in warm, humid areas in the summer. Relative humidity may be close to 100% early in the morning when the air is still cool, and may go down to 65-70% by mid afternoon. However, the actual amount of water vapor (measured as mass of water vapor per mass of the air volume) will actually be greater.

User Avatar

Wiki User

14y ago

What else can I help you with?