Module 7 (Precipitation)

1. Explain how rain shadow regions form on the leeward side of mountains.

Moist air is forced to rise due to a mountain, which causes precipitation, then when air reaches the top of mountain, it goes down but dries leaving a drier air.

How do cloud droplets grow from water vapor to raindrop size?

Collision coalescence: smaller droplets collide with larger droplets merging into larger droplets.

What are the 2 processes involved in generating warm rain?

Condensation

Collision coalescence

What is the process for ice crystal growth in cold clouds called?

Bergeron & ice crystal process

Explain the principle behind cloud seeding.

Injecting clouds with small air particles that act as an Ice Nuclei, so ice crystals grow large enough to form rain.

1. What are the aerosol particles necessary for liquid condensation called? Give 1 example

Ice Nuclei, such as silver iodide, or volcanic ash.

What are the aerosol particles required for freezing of supercooled droplets or ice formation called? Give 1 example.

What is the difference between sleet and freezing rain?

Sleet, starts as snowflakes, melt, then refreeze into pellets

Freezing rain starts as snowflakes melt and don't refreeze.

How does hail form?

Hail forms from frozen water being brought back up into clouds due to updrafts.