What is an air mass? describe how they are named and characteristics (example, what does “m” stand for and what type of air does it bring? )

An air mass if a distinct body that creates a homogeneous mixture of temperature, humidity, and stability that extends through the lower half of the atmosphere. 

m --> maritime (wet)
c --> continental (dry)
A --> Arctic 
P --> Polar
T --> Tropical 
E --> Equatorial 
AA --> Antarctic

The CONTINENTAL POLAR air mass only forms in the Northern Hemisphere. An area covered by this air mass (cP) in winter experiences cold, stable air, clear skies, high pressure, and antcyclonic wind flow.

The MARITIME POLAR air mass in the Northern Hemisphere sits over the Northern Oceans and are cool, moist, unstable, and prevail throughout the year.

There are two MARITIME TROPICAL air masses --> the mT Gulf/Atlantic + the mT Pacific

Hope that helps!  

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