CHAPTER 8- Air mass

Question 0

What is a Canadian Air Mass?

Answer 0

South bound frigid air mass that clashes with north bound tropical air from Gulf of Mexico. As it advances, it modifies and becomes warmer.

Question 1

What is an air mass?

Answer 1

A large body of air usually 1600KM or more across, that is characterized by homogenous physical properties at any given altitude. It modifies the area it covers with its temperature and moisture.

Question 2

What is a source region?

Answer 2

Areas where air masses originate. They need an extensive and uniform area and an an of general stagnation or low atmospheric circulation.

Question 3

The air mass type most likely to form thunderstorms is?

Answer 3

mT

Question 4

An air mass from the Gulf of Mexico that moves northward over the U.S. In winter would be labeled

Answer 4

mT

Question 5

An ideal source region of air masses should be

Answer 5

Physically uniform and have general stagnation of atmospheric circulation.

Question 6

The cP air-mass in North America originates in

Answer 6

Interior Alaska and Canada

Question 7

Most of the precipitation for the region east of the Rocky Mountains comes from

Answer 7

mT air masses

Question 8

When an area is experiencing several consecutive days of rather constant weather, it is experiencing

Answer 8

Air-mass weather

Question 9

Characteristics of an air mass source region include

Answer 9

Uniformity of temperature and moisture

Question 10

In North America, the only air mass that forms only in the summer is

Answer 10

cT

Question 11

The air masses that have the greatest influence on weather conditions in the Midwestern US are

Answer 11

cP and mT

Question 12

An mP air mass is

Answer 12

Humid and cold

Question 13

An air mass is often modified as it moves over the Earth’s surface. This modifications is largely due to

Answer 13

Contact with the ground below

Question 14

The coldest and driest winter air-mass in North America is the

Answer 14

cA

Question 15

Why are the cT air masses of minor importance for the US?

Answer 15

No large source region is near the U.S.

Question 16

Why are maritime air masses from the North Atlantic of only limited concern for weather in the U.S.?

Answer 16

Prevailing winds move them away from the U.S.

Question 17

A cT air mass is

Answer 17

Warm and dry

Question 18

Lake-effect snow is associated with which type of air mass?

Answer 18

cP

Question 19

The air mass that provides much of the moisture for precipitation in the central and eastern United States

Answer 19

mT

Question 20

This air mass may produce an occasional northeaster in the winter

Answer 20

mP

Question 21

Which of these is not a process by which air masses are modified?

Answer 21

Calm winds. Processes that contribute to air modification is cooling from below, heating from below, evaporation of water, and limiting over mountains.

Question 22

An air mass is a body of air with

Answer 22

Similar values of temperature and moisture in the horizontal