WEATHER THEORY

Question 1

Composition of the Atmosphere

Answer 1

78% Nitrogen, 21% Oxygen, and 1% trace gases

Question 2

Atmospheric Circulation

Answer 2

The uneven heating of earths surface

Question 3

Atmospheric Pressure

Answer 3

Atmospheric pressure decreases by 1” hg for every 1,000 ft of altitude gain.

Question 4

measurement of atmospheric pressure

Answer 4

29.92 inches of mercury (inHg) or 1013 millibars (mb). 1 inHg = 34 mb. ST temp: 15°C (59°F)

Question 5

Wind Patterns

Answer 5

Flow of air from areas of high to low pressure

Question 6

Coriolis Force

Answer 6

Force created by Earth’s spin, deflects air to the right

Question 7

Convective Currents

Answer 7

Rising and sinking air caused by temp differences

Question 8

Atmospheric Stability

Answer 8

Ability to resist vertical motion

Question 9

Inversion

Answer 9

A layer of warm air above cooler air

Question 10

Moisture and Temperature

Answer 10

The amount of water vapor and heat in the air

Question 11

Relative humidity

Answer 11

The amount of moisture in the air compared to the maximum it can hold.

Question 12

Temperature/Dew Point Relationship

Answer 12

The difference between the air temperature and the dew point.

Question 13

Saturation

Answer 13

The point at which the air can hold no more moisture.

Question 14

Dew and Frost

Answer 14

Water droplets or ice crystals formed on surfaces due to cooling.

Question 15

Fog

Answer 15

A cloud that touches the ground

Question 16

Clouds

Answer 16

Visible masses of condensed water vapor in the sky

Question 17

Ceiling

Answer 17

Height of the lowest cloud layer.

Question 18

Visibility

Answer 18

Distance you can see clearly

Question 19

Precipitation

Answer 19

Water falling from the sky

Question 20

Air masses

Answer 20

Large bodies of air with similar temperature and humidity

Question 21

Fronts

Answer 21

Boundaries between different air masses

Question 22

Warm front

Answer 22

A warm air mass replacing a colder one

Question 23

Cold front

Answer 23

A cold air mass replacing a warmer one

Question 24

Stationary front

Answer 24

A front that isn’t moving

Question 25

Occluded front

Answer 25

When a cold front overtakes a warm front.

Question 26

Turbulence

Answer 26

Sudden change in wind speed or direction

Question 27

Low-level wind shear

Answer 27

Rapid change in wind direction or speed near the ground.

Question 28

Icing and freezing

Answer 28

The formation of ice on aircraft surfaces (Clear, Glaze, inter-cycle, Detected Mixed, Residual, Rime, Runback) -15c

Question 29

Thunderstorms

Answer 29

Air must have enough water vapor, an unstable lapse rate, and an initial lifting action

Question 30

Microburst

Answer 30

A sudden, intense downdraft of air that can cause significant wind damage. [less than 1 mile, can be as strong as 6000 fpm, appearing virga, ring of dust, seldom last longer than 15 min

Question 31

A

Answer 31

Arctic- From the north pole

Question 32

cP

Answer 32

Continental Polar- Cold lands

Question 33

mP

Answer 33

Maritime Polar- Cold waters

Question 34

cT

Answer 34

Continental Tropical- Warm Lands

Question 35

mT

Answer 35

Maritime Tropical- Warm waters