Humidity

Question 1

Freezing

Answer 1

Liquid to Solid
Absorbs Latent Heat
Freezing nuclei needed
Supercooled without nucleus to -50 before freezing
Supercool unstable

Question 2

Condensation

Answer 2

Gas to liquid
Latent Heat released
Requires nucleus for water vapour

Question 3

Psychrometer

Answer 3

Wet + Dry bulb
Wet cloth if evaporation occurs latent heat will be released causing variation in thermometers

Question 4

Absolute Humidity

Answer 4

Amount of water vapour in volume of air (Mass)
G/m3

Question 5

Vapour Pressure

Answer 5

Pressure from water vapour molecules

Question 6

Humidity Mixing Ratio

Answer 6

Amount of water vapour in mass of dry air

Question 7

Saturation

Answer 7

Max amount of water air can hold

Question 8

Sublimation

Answer 8

Solid to gas
No nuclei needed
Latent heat released

Polar region terrestrial radiation

Question 9

Deposition

Answer 9

Gas to solid
Latent heat absorbed
Nuclei required

Question 10

Dew Point

Answer 10

Temp needed for saturation
Close temp = more likely for condensation and development of fog/cloud

Dry air has lower dew point
Warm air has higher dew point

Question 11

Relative Humidity calculation

Answer 11

Amount of water in air/max water vapour air can hold x 100

Question 12

Temp Effects on dew point

Answer 12

Increasing/decreasing temp on unsaturated air has no effect on dew point (Dew point can only be equal to or lower than the temp of air mass)

Decreased in saturated will condense and decrease dew point

Question 13

Diurnal variation in humidity

Answer 13

Dawn/evening - Temp decrease mean higher relative humidity

Afternoon - temp increases lower relative humidity

Question 14

Relative Humidity calculation from temp and dew point

Answer 14

100 - (temp-dew point) x 5

Question 15

Neutral Stability

Answer 15

ELR = DALR in dry air
ELR = SALR for moist air

Question 16

Calculating RH from temp and dew point

Answer 16

100 - (Temp - Dewpoint) x 5

Question 17

Dry Adiabatic Lapse Rate

Answer 17

1 degree per 100m
3 degrees per 1000ft

Question 18

Saturated Adiabatic Lapse Rate

Answer 18

0.65 degrees per 100m
1.8 degrees per 100ft

Question 19

Water Vapour pressure

Answer 19

Pressure exerted by water vapour molecules in the air
Saturation vapour pressure increases when temperature increases

Liquid surface easier for water molecules to break free and evaporate than a solid surface

Question 20

Adiabatic process is

Answer 20

Process in which no heat transfer takes place.

Temp changes due to expansion or compression - no heat is added or taken away

Question 21

What process is latent heat absorbed

Answer 21

When additional energy is required to break the bond holding the molecules together

Melting and evaporation

Question 22

Saturated water vapour pressure does what with temperature

Answer 22

Increases

Question 23

Another name for a pshychometer is

Answer 23

Hygrometer