Upper Air Analysis
Vorticity
The Jet Stream
Get Low
Potpourri
100
The 850 mb level is approximately how high above sea level?
1.5 km
100
In the Northern Hemisphere, positive vorticity advection is associated with what type of vertical motion?
Rising motion
100
True/False: The Polar jet stream is found at a higher altitude compared to the Subtropical jet stream
false
100
In the Northern Hemisphere, which direction do low-pressure systems rotate?
counterclockwise
100
What are contours of wind speed called?
isotachs
200
The 500 mb level is approximately how high above sea level?
6 km
200
Is clockwise rotation associated with positive or negative vorticity?
negative (vertical) vorticity
200
In the N.H., the polar jet primarily flows from which direction?
west to east
200
If divergence at upper levels is greater than convergence into a low pressure system at the surface, how will the low evolve?
pressure will drop
200
Which moves faster, cold fronts or warm fronts?
cold fronts
300
On upper-air station plots, temperature is reported with these units.
Celsius
300
Vorticity advection is typically analyzed on upper air charts at what specific pressure level?
500 mb
300
What causes changes in jet stream "strength"
north/south temperature gradient
300
A localized area of reduced geopotential height is called
trough
300
In the Northern Hemisphere, if air is moving towards the west, which direction will the Coriolis force deflect it?
towards the north
400
What parameter is shown in the lower-left corner of upper air models?
dew point depression
400
What process causes shear vorticity?
changes in wind speed
400
"Zonal" refers to flow directed primarily in which direction?
west to east
400
Which location in the image would you expect to find low pressure at the surface?
B
400
What is the name of the equation that describes the parameters that control atmospheric thickness
Hypsometric equation
500
What are contours of geopotential height are called?
Isohypses
500
What is the difference between relative and absolute vorticity?
absolute vorticity includes vorticity due to the rotation of the Earth
500
In the Northern Hemisphere polar jet stream, what direction does the pressure gradient force point towards?
North
500
Why does air spiral into a low pressure near the surface, but not at upper levels?
Friction disrupts balance, allowing air to flow towards the center of the low
500
The balance between pressure gradient force and Coriolis force is called
Geostrophic Balance