ENVIRSC 1A03 Lecture Notes - Lecture 6: Vapor Pressure, Humidity, Fluid Parcel

• School: McMaster University
• Department: Environmental Science
• Course: ENVIRSC 1A03
• Professor: Luc Bernier

Document Summary

Absolute humidity : mass of water vapour as a ratio to the volume of air, not commonly used due to frequent change in volume. If amount of water vapour in a parcel air remains constant, increase in parcels volume will decrease absolute humidity. A decrease in volume, increases absolute humidity. Water vapour molecules combine with water surface and bond with adjacent surface: there is an equilibrium between evaporation and condensation during saturation, upon saturation condensation begins and water returns to surface, saturation. Relative humidity: dew point temperature, temperature at which saturation occurs in the air, dependent upon amount of water vapour present, measure of actual moisture in air as indicate amount of water vapour, high dew point. Increase in air temp with no change in water vapour content decreases relative humidity of air this occurs because saturation vapour pressure increases with warm air , more water vapour molecules can be held in warmer air.