What is the term that describes the ratio of moisture in the air compared to its maximum capacity?

The term that describes the ratio of moisture in the air compared to its maximum capacity is relative humidity. This concept is essential in understanding atmospheric conditions and weather patterns. Relative humidity is expressed as a percentage and indicates how close the air is to being saturated with water vapor. When relative humidity reaches 100%, the air is fully saturated, and any additional moisture may condense into dew or precipitation.

Absolute humidity, in contrast, measures the actual amount of water vapor present in a given volume of air without considering the air's capacity to hold moisture at a given temperature. Specific humidity provides the mass of water vapor relative to the total mass of air, including dry air and water vapor, but does not directly reflect the air's moisture saturation level. The saturation point refers to the condition when air can no longer hold additional moisture and is not a ratio but rather a state of humidity. Understanding relative humidity is crucial in various fields, particularly in aviation, as it affects aircraft performance and atmospheric conditions.