Lesson 107 Flashcards
(13 cards)
An airmass is a large section of the troposphere that has ______________________________________ .
… relatively uniform temperature and moisture in the horizontal.
An air mass is formed when a large section of air ________ the temperature and moisture characteristics of a vast area of the earths surface.
acquires
The types of air mass that can occur in North America are:
- Continental Arctic (winter only) - dry and very cold
- Maritime Arctic - humid and cold
- Maritime Polar - humid and mild
- Maritime Tropical - humid and warm
An air mass with very cold air at the surface (cA) will have a weak temperature lapse rate and the air will be _________ . cA is the most ________ air mass at it’s source region.
Stable
Stable
An air mass with very warm air at the surface (mT) will have a strong temperature lapse rate and the air will be ________ . mT is the most __________ air mass in its source region.
Unstable
Unstable
Polar air mass forms in the _________ latitudes.
Temperate
Air mass leaves its source region.
If the air is cooled from below, the air becomes more _________
If the air is warmed from below, the air becomes more __________
Stable
Unstable
Factors that may change the temperatures of air masses are: 1C 2C 3O 4M 5D 6T
- Changes in latitude
- Change of seasons
- Ocean currents
- Movement from over water or land
- Diurnal variations
- Topography
how would an air mass become destabilized?
By heating from below
By cooling aloft
How would an air mass become stabilized?
By cooling from below
By heating aloft
In summer
An offshore flow will ________ the air and ________ the air.
An onshore flow will _________ the air and _________ the air.
Cool, stabilize
Warm, destabilize
In winter
An offshore flow will _______ the air and ________ the air
An onshore flow will _________ the air and ________ the air
Warm, destabilize
Cool, stabilize
If air is ________, thicker clouds can form.
If an air mass is relatively ________, clouds will be thinner
Moist (NS, AS, TCU, CB)
Dry (SC, AC)
