What is Air mass?
[[File:Air masses.svg|thumb|Bergeron classification of global air masses]] An '''air mass''' is a [[volume]] of [[air]] defined by its [[temperature]] and [[water vapor]] content. Air masses cover many hundreds or thousands of [[square mile]]s. Colder air masses are called [[polar]] or [[arctic]], while warmer air masses are called [[tropical]]. {{weather-stub}} [[Category:Meteorology]]