Air mass

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 miles. Colder air masses are called polar or arctic, while warmer air masses are called tropical.

Air Mass Media

Different air masses which affect North America as well as other continents, tend to be separated by frontal boundaries
Picture of cold front (left part of the image) moving over the Czech Republic
Lake-effect snow bands near the Korean Peninsula

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