GEOG 155 Chapter Notes - Chapter 11: Water Vapor, Dew Point, Evapotranspiration
Document Summary
Heat involved in melting is called the latent heat of fusion: evaporation (also known as vaporization) is when it goes from liquid to gas. Latent heat of vaporization is the heat associated with evaporation: sublimation is the change of water from solid to gas. Humidity is the amount of water vapor present in a column of air: one measure of it is the pressure of water vapor in a volume of air. Vapor pressure: the pressure exerted by the molecules of water vapor in the atmosphere: other measurements are dew-point temperature, specific humidity, and relative humidity. Saturated air has the maximum number of water vapor molecules possible at the given temperature: saturation vapor pressure will be reached eventually, and the vapor in the cooled air condenses into liquid water droplets (condensation) Dew: the fine water droplets that accumulate outside because of cooler temperatures at night: dew-point temperature: the temperature at which air becomes saturated and at which condensation occurs.
