Air Masses Flashcards
What is an air mass?
A block of air which has uniformity in the horizontal plane
- Temp
- Moisture content
- ELR
How are air masses classified?
By humidity and type/temperature
What is a stable air mass?
When its cooled from below
What is an unstable air mass?
When its warmed from below
What is the source of a tropical maritime air mass?
Warm and moist air over waters of the Atlantic Ocean between the Azores and Bermuda
How does the tropical air mass change as it moves?
- Stability increases
- Air becomes saturated
What is the source of the tropical continental air mass?
North Africa and the Sahara - air mass is dry and unstable
How does the tropical continental air mass change on route?
- Slightly cools from below by less warm ground
- Stability increases
- Slight increase in moisture
What is the source of the polar maritime air mass?
Very cold and dry airmass from Canada and Greenland
How does the polar maritime air mass change on route?
- Temp rises gradually
- Becomes unstable to great depth
- Moist
What is the source of the returning polar maritime air mass?
Very cold and dry air mass from Canada and Greenland
How does the returning polar maritime air mass change on route?
During passage south, air becomes unstable and moist moving north east is passes over cooler water making it stable in its lowest layers
What is the source of an artic maritime air mass?
Very cold and dry air mass from the North Pole and the artic ocean
How does the artic maritime air mass change on route?
- Temp rises rapidly
- Becomes unstable
- Moist
What is the source of the polar continental air mass?
The snow fields of Eastern Europe and Russia, very cold and dry in winter, classified as tropical continental in summer
