What does the term 'relative humidity' refer to?

Relative humidity is a key concept in meteorology that describes the amount of moisture present in the air relative to the maximum amount of moisture that the air can hold at a given temperature. This relationship is expressed as a percentage, indicating how close the air is to being fully saturated with water vapor.

As temperature and atmospheric pressure change, the amount of moisture the air can hold also changes, which is why it's essential to consider both current moisture content and temperature when discussing relative humidity. For instance, warm air can hold more moisture compared to cold air. Therefore, at a specific temperature, relative humidity provides insight into how much moisture is present compared to the potential maximum, impacting weather patterns and human comfort levels.

Understanding relative humidity is vital, as it influences weather conditions, precipitation, cloud formation, and comfort levels for living beings.