Chapter 7 Flashcards
(27 cards)
Cold front
When advancing cold air mass meets & displaces warmer air.
Twice as steep as warm front.
Moves faster than warm front.
Lead to lots of precipitation in short time
What are the 4 types of fronts?
Cold
Warm
Stationary
Occluded
Warm front
When warm air mass meets colder air.
More gentle than cold front.
Stationary fronts
When neither air mass displaces the other
Occluded fronts
Formed when a cold overtakes a warm front.
Air masses
Large particles of air that are distinct from one another
Characteristics of air masses that make it recognized as distinct
- It must be large
- It must have uniform properties in all dimensions
- It must travel as a unit. Must not change as it moves through other air
How do air masses originate?
They stagnate overtop of a region for so long that they gain their properties.
Usually happens in high pressure areas
A- Antarctic
Very cold, dry & stable
Continental polar -cp
Cold, dry, very stable
Maritime polar- mp
Cold, moist, relatively unstable
continental tropical
Hot, very dry, unstable
Maritime tropical
Warm, most, varying stability
Equatorial
Warm, very moist, unstable
Low latitude air mass
Warm or hot
High latitude air mass
Cold or cool
Midlatitude anticyclones
Larger than cyclones
Clockwise, divergent air flow
No fronts
Calm
Midlatitude cyclones
Migrate w to east Usually form when cold & warm air meet. 1000 miles in diameter Oval shape Northern hemisphere Counterclockwise
Cyclogenesis
Birth of a cyclone
Cyclogenesis lasts…
3 to 10 days
Birth of cyclone ends when
Cold front catches up to warm front
Occlusion
Death of cyclone. Once all warm air is pushed up, there’s no more instability
Hurricanes get named once they reach
39 mph
Considered a hurricane when
Reaches 74 mph
