Module 8 air masses Flashcards
What is an air mass?
A volume of air with a defined temperature and water vapor content.
How does an air mass change temperature?
It changes temperature when it sits above a hot or cold area.
What happens to the air over a black car in summer?
It is much hotter than in the surrounding area.
What is the effect of color on heat absorption?
Black absorbs and radiates heat, while white reflects heat.
What is a source region?
The areas on Earth where the air mass begins to form.
How do air masses that form over water differ from those over land?
Air masses over water carry much more moisture; those over land are drier.
Where do continental polar air masses form in North America?
In Canada and the northern parts of the United States.
Where do Arctic air masses form?
Over the Arctic region of the globe.
What is the origin of maritime polar air masses in the Pacific?
They originate close to Alaska and northern Canada.
Which area do maritime tropical air masses in the Pacific originate from?
The southern part near Central America.
What classification is given to air masses over water?
Maritime.
What classification is given to air masses over land?
Continental.
What are the characteristics of air mass sources?
Uniform, characterized by light surface winds and high pressure.
What are the five major types of air masses?
- Continental tropical (cT)
- Continental polar (cP)
- Continental arctic (cA)
- Maritime polar (mP)
- Maritime tropical (mT)
Describe continental tropical (cT) air masses.
They form over warm continents, are dry, and contain warm air.
Describe continental polar (cP) air masses.
They form over cold source regions, are cold, and dry.
What is unique about continental arctic (cA) air masses?
They are extremely cold and bring extreme cold to upper parts of North America.
How do maritime polar (mP) air masses differ from continental polar air masses?
They are more humid because they form over cold water.
Where are maritime tropical (mT) air masses found?
Along the Equator and they are humid.
What happens to air masses as they move away from their source regions?
They change with their surroundings, altering moisture or heat content.
What is air mass modification?
The process by which an air mass takes on characteristics of the surface over which it passes.
What can air mass modification create?
Greater stability or instability depending on the surface temperature.
