Cloud And Precipitation Processes

Question 1

What is a hygroscopic nuclei?

Answer 1

A particle which is attracted to water and forms a dilute salt solution

Question 2

What is coalescence?

Answer 2

The growth of raindrops by individual drops colliding and merging with other drops

Question 3

What Relative Humidity does pure water require for condensation to occur?

Answer 3

300%

Question 4

At what temperature do super cooled droplets occur?

Answer 4

< 0 Degrees C

Question 5

What Relative Humidity does super saturated air have?

Answer 5

1%

Question 6

Give 4 examples of Hygroscopic Nuclei

Answer 6

1. Dust
2. Smoke
3. Clay
4. Sea Salt

Question 7

Give three particle sizes in relation to hygroscopic nuclei?

Answer 7

1. Aitken
2. Large
3. Giant

Question 8

What size are Aitken particles?

Answer 8

0.001 - 0.1 um

Question 9

What size are Large particles?

Answer 9

0.2 - 1 um

Question 10

What size are Giant particles?

Answer 10

> 10 um

Question 11

What are the three paths to saturation?

Answer 11

1. Adiabatic cooling and the lifting condensation level
2. Free convection
3. Forced convection

Question 12

What are the four results of condensation near the ground?

Answer 12

1. Dew
2. Radiation Fog
3. Advection Fog
4. Frost

Question 13

What are the 5 conditions needed for condensation near the ground?

Answer 13

1. Clear night
2. Moist air
3. 1-2 m/s of wind
4. Removal of latent heat through further cooling
5. Ground and leaves as condensation nuclei

Question 14

A fog point occurs below the…..

Answer 14

Dew Point

Question 15

A frost point occurs below the……

Answer 15

Fog Point

Question 16

What are the 6 processes of cloud growth?

Answer 16

1. Condensation
2. Bergeron Process
3. Coalesence or Collision
4. Aggregation
5. Accretion
6. Seeder-Feeder Mechanisms