Pressure Gradient Force/ Wind balance
Air Columns
Precipitation
Troughs/ Ridges
Misc.
100

Wind flows from what pressure to what pressure? 

High pressure to low pressure. 

100

Which column of air is taller, warm or cold?

Warm. 

100

How is a warm cloud characterized? 

A cloud that is completely above the freezing level. 


100

Troughs have areas of ___ height while ridges have areas of ____ height.

Low, high. 

100

True or False: The closer together isobars are the stronger the winds between them. 

True. 

200

True or False: PGF winds flow perpendicular to isobars (lines of constant pressure. 

True. 

200

If the columns of air for 2 areas are equal, is there any air transfer between the 2?

No. Equal pressure = no wind.

200

How is a cold cloud characterized? 

A cloud that exists all or partly above the freezing level. 

200

(500mb) Troughs create areas of ___ temperature while ridges create areas of ____ temperature.

Low, high. 

200

Why doesn't wind flow directly from pressure systems?

The Coriolis Force. 

300

By keeping the change in pressure constant but decreasing the distance, PGF increases or decreases? 

PGF increases.

300

What is the air pressure at mid levels for a warm column of air?

High.

300

When freezing rain falls and freezes on the surface, what process occurred here? 

Accretion. Ice crystals collide with super cooled droplets. Being supersaturated  (RH>100%), this precipitation freezes on contact with a surface. 

300

Which pressure feature typically has a lower 500mb height, a trough or ridge?

Trough. 

300

Sleet requires what type of warm layer? 

Shallow warm layer for partial melting, deep cold layer to allow time to re freeze. 

400

Change in pressure over change in distance is always multiplied by what? 

-1/rowe (density)

400

What is the mid level pressure for a cold column of air?

Low. 

400

What process occurs for sleet to fall? 

Fracturing. Falling ice particles collide and fracture into smaller pieces. 

400

Identify on this map where the ridge is located and where the trough is located.

Trough: Eastern U.S.

Ridge: Western U.S.

400

What are the three main forces that act on air?

1. Pressure Gradient Force.

2. Coriolis Force.

3. Frictional Force.

500

PGF Sign Problem

                     O=990mb

O=1000mb         A                O=1020mb

                      O=1010mb

dp/dx= 1020-1000= +

dp/dy= 990-1010= -

500

Explain the airflow process between these two air columns. 

From top right: High to low, sinks, high to low, rises. 
500

What process assists in the creation of snowflakes? 

Aggregation. Falling crystals collide and stick together to other crystals. 

500

Having a trough and ridge close together creates a strong or weak PGF?

Strong. 

500

Freezing rain requires what kind of warm layer?

Deep warm layer to allow for complete melting, shallow cold layer to create supercooled droplets.