Stability And Cloud Formation

Question 1

Whats the verticle movement of air called?

Answer 1

Convection.

Question 2

Whats the horizontal movement of air called?

Answer 2

Advection.

Question 3

What altitude is the friction layer?

Answer 3

3000ft

Question 4

What is orographic lift?

Answer 4

Air moving up a mountain.

Question 5

When air passes over a mountain, if the altitude of the air sinks back, what is the atmospheric stability?

Answer 5

Stable.

Question 6

When air passes over a mountain, if the altitude of the air stays flat, what is the atmospheric stability?

Answer 6

Neutral

Question 7

When air passes over a mountain, if the altitude of the air continues to rise, what is the atmospheric stability?

Answer 7

Unstable.

Question 8

Whats used to measure the lapse rate?

Answer 8

Radiosonde.

Question 9

What is adiabatic cooling?

Answer 9

Air rising and then expanding.

Question 10

What is adiabatic warming?

Answer 10

Air sinks and compresses.

Question 11

Provided water vapour does not condense when it rises, the parcel of air cools at x degrees / 1000ft.

Answer 11

3

Question 12

Provided water vapour does not condense when it rises, the parcel of air cools at x degrees / 100m.

Answer 12

1

Question 13

What is the dry adiabatic lapse rate in feet and metres?

Answer 13

3’/1000ft - 1’/100

Question 14

What is the saturated adiabatic lapse rate for 1000ft?

Answer 14

1.8’

Question 15

What is the saturated adiabatic lapse rate for 100m.

Answer 15

0.6.

Question 16

Why does a saturated adiabatic lapse rate vary with height?

Answer 16

Latent heat released due to change of state.

Question 17

Whats is the environmental lapse rate per 1000ft?

Answer 17

1 degree

Question 18

Absolutely stable atmosphere - air (does/does not) rise buoyantly?

Answer 18

Does not.

Question 19

In a blank blank atmosphere, air rises buoyantly.

Answer 19

Absolutely unstable.

Question 20

What happens to air in an absolutely unstable air?

Answer 20

It rises and forms a cloud.

Question 21

Any thing below the dew point is deemed at what lapse rate?

Answer 21

Dry.

Question 22

What stability is turbulence is likely?

Answer 22

Absolute instability.

Question 23

What cloud types would you see in absolute instability?

Answer 23

Cumulus, towering cumulus, cumulonimbus,

Question 24

What is conditional instability?

Answer 24

ELR is in between DALR and SALR

Question 25

In a conditionally unstable atmosphere, blank air does not rise buoyantly.

Answer 25

Unsaturated.

Question 26

In a conditionally unstable atmosphere, blank air does rise buoyantly.

Answer 26

Saturated.

Question 27

If air is cooled from below, what is the stability?

Answer 27

Stable.

Question 28

If air is warmed from below, what happens to the stability?

Answer 28

Unstable.

Question 29

How do you get rid of cloud?

Answer 29

Adiabatic warming (subsidence) -solar radiation

Question 30

ELR less than 1.8°C/1000ft air will be absolutely blank, dry or saturated.

Answer 30

Stable.

Question 31

ELR more than 3°C/1000ft air will be absolutely blank, dry or saturated

Answer 31

Unstable.

Question 32

ELR between 3°C/1000ft and 1.8°C/1000ft, air will be blank blank. –Unstable if saturated –Stable if dry

Answer 32

Conditional instability.

Question 33

What are the standards for a DALR?

Answer 33

Fluffy cloud - fat water droplets - flat line on altitude tempurature graph

Question 34

What are the standards for SALR?

Answer 34

Stable - smooth - stratus - small water droplets - steep line on a alt temp graph

Question 35

When two humid, but yet unsaturated air masses with different temperatures mix, the result can be...

Answer 35

Cloud formation.

Question 36

In winter, after breaking through a low level inversion during descent and assuming the pilot does not intervene, what will happen to visibility?

Answer 36

Decrease.

Question 37

In winter, after breaking through a low level inversion during descent and assuming the pilot does not intervene, what will happen to thrust?

Answer 37

Increase.

Question 38

A surface based inversion is a characteristic of nocternal blank on blank nights

Answer 38

Radiation clear

Question 39

Lower layers of air are heated by x, which means transferring heat by molecular interactions between ground and air.

Answer 39

Conduction

Question 40

How could a flight crew visually identify that a tropical squall line is about to pass over their destination aerodrome, and what hazard should they expect to encounter on the approach?

Answer 40

Roll cloud

Question 41

What are the primary factors driving heat transfer from the ground to the lower levels of the atmosphere?

Answer 41

Conduction and turbulence

Question 42

A moist, stable layer of air is forced to rise against a mountain range and the stability does not change. Which of the following phenomena may develop?

Answer 42

Stratiform clouds.