Download SCI 100 Air Mass Handout

SCI 100 Air Mass Handout
Air Masses around the world

What they are:
 A large body of air (10,000s of square kilometers)
 Similar or uniform temperature and moisture characteristics at all horizontal levels

Where they form:
 Anticyclones (H) with very light surface winds in their center that sit over an area for a
while will take on the characteristics of the surface below
 Think about the real-world areas Subtropical Highs and Polar Highs

DO NOT FORM:
 In mountainous regions
 In areas where Middle Latitude Cyclones or Tropical Cyclones exist

Named (with abbreviations) for their source region
 Flat regions like oceans (maritime: m) ; deserts and tundras (continental: c)
 Source regions are warm regions (Tropical: T) and cold regions (Polar: P)
Classifications of Air Masses:
 Four most common listed in the table below (which is similar to Table 8.1, p 203)
 Learn by characteristics, name, and two-letter designation
Characteristic
moist (wet) (humid)
dry (very little water vapor)
Cold (cool)
mP (maritime Polar)
cP (continental Polar)
Warm (hot)
mT (maritime Tropical)
cT(continental Tropical)
One “Extreme” Air Mass: continental Arctic (cA) which is Very Cold and Very Dry

Air Masses
 Move and Modify
 Interact or clash
 Can also have their own type of weather