Atmospheric Composition

Question 1

Natural Air

Answer 1

Natural Air = Dry air + Condensation Nuclei +

Water Vapor

Question 2

Coriolis Force

Answer 2

apparent force caused by the unequal speed of rotation of the earth’s surface. Deflects non-steerable bodies to the right in the N. Hemisphere.

Question 3

Prevailing Westerlies

Answer 3

Group of winds which move our weather from the west to the east.

Question 4

Methods of Heat Transfer

4 Types

Answer 4

Radiation

Conduction

Convection
-Strongest thermal currents occur over land surface during daylight hours

Advection - wind

Question 5

Air Masses

Classification

Answer 5

Water Vapor Content:

• c = Continental Air Mass (Dry Air)
• m = Maritime Air Mass (Moist Air)

Temperature: (by latitudes of origin)

• A = Arctic Air Mass (70° - 90°)
• P = Polar Air Mass (40° - 60°)
• T = Tropical Air Mass (10° - 30°)
• E = Equatorial Air Mass (0° - 10°)

Symbol Name Description

cA Continental Arctic coldest, dry

cP Continental Polar cold, dry

mP Maritime Polar cold, moist

mT Maritime Tropical warm, moist

cT Continental Tropical warm, dry

E Equatorial warmest, moist

Question 6

What are the components of dry air?

Answer 6

78% nitrogen
21% oxygen
1% miscellaneous gases

Question 7

In addition to the gases present in dry air, natural air contains a variable amount of what?

Answer 7

water vapor and condensation nuclei

Question 8

The height of the troposphere is variable from ______ feet at the poles to _____ feet at the equator.

Answer 8

25,000’ at poles

60,000’ at equator

Question 9

Which atmospheric layer contains clouds that are of greatest concern to the aviator?

Answer 9

Troposphere

Question 10

The most important element of weather, usually not found above the troposphere, is ______.

Answer 10

Moisture

Question 11

What is the basic cause of atmospheric circulation?

Answer 11

Unequal heating of the earth by the sun

Question 12

What are the three causes of the three-cell circulation?

Answer 12

Coriolis force
unequal heating
tilt of the earth

Question 13

The air at the equator rises due to being heated by the warm surface. What type of pressure does this lifting action cause?

Answer 13

low pressure

Question 14

In the northern hemisphere, what direction is the prevailing wind between the 30° and 60° latitudes? (Wind is ALWAYS reported FROM a direction.)

Answer 14

West

Question 15

What are the four types of heat transfer?

Answer 15

Radiation
Conduction
Convention
Advection

Question 16

How is heat transferred through the process of radiation?

Answer 16

By electromagnetic waves

Question 17

What is the difference between insolation and terrestrial radiation?

Answer 17

Insolation is the radiation from the sun to the surface. Terrestrial radiation is the radiation given off by the earth.

Question 18

What is the exchange of heat by physical contact called?

Answer 18

Conduction

Question 19

Describe the difference between convection and advection

Answer 19

Convection is the exchange of heat in a vertical direction. Advection is the exchange of heat in a horizontal direction.

Question 20

What conditions would cause the strongest thermal currents?

Answer 20

Landmass in the daytime

Question 21

What is the standard temperature lapse rate?

Answer 21

2° per 1,000’

Question 22

A layer of air, characterized by an increase in temperature with altitude, is referred to as a ____?

Answer 22

Temperature inversion

Question 23

What would prevent a radiation (nocturnal) temperature inversion?

Answer 23

Overcast sky/Greenhouse effect

Question 24

Explain the role of clouds in the greenhouse effect.

Answer 24

Clouds re-radiate terrestrial radiation back to the surface, preventing the escape of heat energy into space and a nocturnal temperature inversion.

Question 25

Cold, dense air lifting warmer, less dense air is an example of what type of temperature inversion?

Answer 25

Frontal

Question 26

The basic characteristics of any air mass are

Answer 26

Temperature and moisture content

Question 27

Which of the following would be a source region for a warm, moist air mass?

a. Northern Pacific Ocean
b. Northern Mexico
c. Siberia
d. Gulf of Mexico

Answer 27

d. Gulf of Mexico

Question 28

Which general direction does the North American High (cP) air mass move to?

Answer 28

Southeast

Question 29

Which general direction does the Bermuda High (mT) move to?

Answer 29

Northeast

Question 30

What classification would describe a cold, dry air mass?

Answer 30

cP