17 terms

Geography Ch. 6

Air Masses
Large bodies of air with uniform temp and moisture characteristics
Weather Systems
recurring pattern of atmospheric circulation associated with characteristic weather, such asa cyclone or anticyclone
Source Region
air moves slowly which allows the air to acquire similar temp and humidity characteristics from the region
contact between two unlike air masses
Cold Front
cold air masses moving underneath warm air mass causing the latter to be lifted. cold air is more dense so it stays near the ground
Warm Front
warm air moves into a cold air mass and the cold air retreats
Occluded Fronts
cold air front takes over warm air and moves it above the cold air
Polar Front
where a polar and tropical air masses are in contact
center of low atmospheric pressure
center of high atmospheric pressure
Midlatitude Cyclone
cold and warm fronts interacting and traveling in the midlatitudes. cold air from the north meets with warm air from the south. dissolves
Tropical Cyclone (hurricane)
forms between 10 and 20 deg N and S latitude, wind speeds 30-50 m/s (65-135 mph)
Easterly Wave
slow moving trough of low pressure within the belt of tropical easterlies. occurs in 5-30 deg latitude N and S
Weak equatorial low
disturbance near equatorial trough, air masses converge creating storms
Tropical Cyclone conditions
start from tropical depressions which have 40mph winds, then intensify into tropical storms becoming a tropical storm at 74mph wind speeds
Eye of hurricane
center of hurricane, clam clear skies
Source Region
area where a large air mass derives it's temperature and moisture characteristics