Meteorology Today, Ahrens Chap 7

Question 1

what does it mean when a cloud droplet is in equilibrium with its environment

Answer 1

Water vapor evaporates and condenses at the same rate

Question 2

What is Saturation vapor pressure

Answer 2

Total number of vapor molecules around the cloud droplet in equilibrium

Question 3

Smaller cloud droplets have greater or smaller rate of evaporation

Answer 3

Greater, as curvature is larger compared to size of water droplet, more water vapor is needed to replace those that are lost

Question 4

What is needed to keep a cloud droplet alive

Answer 4

Supersaturation, Relative Humidity is higher than 100% so water vapor constantly replenishes those that are evaporated.

Question 5

What is curvature effect

Answer 5

Smaller cloud droplets require more Saturation vapor pressure to survive.

Question 6

Relative humidity in a cloud does not typically grow more than what

Answer 6

101 Percent

Question 7

What is the solute effect in clouds

Answer 7

when an impurity, such as salt, replaces a water molecule in the lattice structure of the droplet, the equilibrium vapor pressure surrounding the droplet is lowered.

Question 8

As a droplet grows, what happens to solute effect

Answer 8

solute effect diminishes in effectiveness

Question 9

Describe Collision Coalescence process

Answer 9

Cloud droplets collide with other cloud droplets

Question 10

How can cloud droplets collide to undergo collision coalescence process

Answer 10

Falling droplets collide with others and Rising droplets collide with others(smaller droplets rise faster).

Question 11

Is coalescence between 2 cloud droplets guaranteed if they collide

Answer 11

No, but those of opposite electrical charge are more likely to combine

Question 12

What type of clouds maximize droplet growth

Answer 12

thick clouds with strong updrafts

Question 13

In what type of clouds does the Collision coalescence process operate upon

Answer 13

Warm clouds, clouds that are above freezing at all altitudes

Question 14

What is the glaciated region of a cloud

Answer 14

The region of the cloud that is completely composed of ice crystals

Question 15

Are ice nuclei(nuclei that ice forms on) common in the atmosphere?

Answer 15

No

Question 16

What is Graupel

Answer 16

ice crystals that have supercooled water that freezes on them.

Question 17

Describe bergeron process

Answer 17

in a mixed-phase cloud where both ice crystals and supercooled water droplets exist, the ice crystals tend to grow larger at the expense of the surrounding water droplets, effectively “stealing” water vapor from them and causing the droplets to shrink or even evaporate completely. This is because the ice crystals take water vapor, which is replenished by the water droplets

Question 18

What is sleet

Answer 18

When a falling snowflake falls through warmer air and melts but then falls through the deep
subfreezing surface layer of air, the partially melted snowflake
or cold raindrop turns back into ice, not as a snowflake, but as
a tiny ice pellet called sleet.

Question 19

What is glaze

Answer 19

raindrops that reach the surface as supercooled liquid drop because it melts and the subfreezing surface layer of air is not deep enough to freeze the droplet.

Question 20

What is Rime

Answer 20

small, supercooled cloud or fog droplets strike an object
whose temperature is below freezing, the tiny droplets freeze,
forming an accumulation of white or milky granular ice called
rime