- - extensive body of air that has relatively uniform properties in the horizontal dimension and moves as an entity.
- - large, uniform entity
Origin of Air Masses
Formed by remaining over a uniform land or water which will allow it to develop uniform temperature and humidity.
- - central/northern Canada
- - very cold, very dry, very stable
- - winer
Continental Polar (cP)
- - central/ northern canada
- - cold, dry, very stable air mass
- - winter
maritime Polar (mP)
- as cold an dry as continental polar
Maritime Tropical (mT)
principal source of moisture
Continental Tropical (cT)
summer air mass, hot, dry, unstable
- - zone of discontinuity between unlike air masses
- - Warm front brings warm air masses and a cold front brings cold air masses
- - large migratory low pressure system that occurs within mid lats, moves with westerlies, involving interaction of warm and cold air masses along defined fronts.
- - life cycle could be from a few hours to a few weeks
Origin of MLC
- - originate from rosspy waves
- - follow flow of polar front jet streams
How it dies...
- when cold front overtakes the warm front
- - a large migratory high-pressure cell of the middle latitudes that moves with westerlies.
- - clockwise air circulation and usually no rain
- - air flows down unlike regular cyclone therefore no rain, also no frotns
- - larger than MLC
Relationship between MLC and MLA's
- - both are migratory systems within westerlies.
- - usually form together
- - but can occur independently
- - dominantly in winter and follow polar front jet streams.
- - intense, revolving, rain-drenched, migratory and destructive cyclone in tropics and subtropic latitudes, containing very high wind.
- - North and Central America - Hurricane
- - Western North Pacific- Typhoon
- - Philippines- Baguious
- - Indian ocean and Australia- Cyclone
Characteristics of tropical cyclone
- - low pressure systems, circular shape
- - winds must exceed 74 mph