ATOC 1050 EXAM 2 CU BOULDER WITH
COMPLETE SOLUTIONS
UTC Time Conversion: MDT (Zulu time) - ANSWER-MDT= UTC - 6 hours
UTC Time Conversion: MST (Zulu time) - ANSWER-MST= UTC - 7 hours
Wind - ANSWER-The horizontal movement of air due to horizontal differences in air
pressure
What causes wind? - ANSWER-Unequal heating of the Earth's surface, continually
creates differences in air pressure and results in wind
PGF - ANSWER-Pressure gradient force: the force due to differences in pressure within
the atmosphere that causes air to move and, hence, the wind to blow
Where does air flow in the PGF - ANSWER-High pressure to Low pressure
Forces - ANSWER-Newton's 1stLaw of Motion: an object at rest will remain at rest and
an object in motion will remain in motion (and travel at a constant velocity along a
straight line) as long as no force is exerted on the object
Equation for Force - ANSWER-F (net force) = m (mass) * a (acceleration)
Air Pressure - ANSWER-The pressure exerted by the weight of air above a given point
Sea Level Pressure - ANSWER-14 pounds of force over each square inch of our bodies
How does pressure change with altitude? - ANSWER-The pressure at any given altitude
is equal to the pressure exerted by weight of the air directly above that point, as we
move up through the atmosphere, the density of air decreases
Ideal Gas Law - ANSWER-Pressure = Temperature * Density * Constant
*Think about two air columns* If the number of molecule in the column stays constant
and the column cools... - ANSWER-It will become more dense and shorter
*Think about two air columns* If the number of molecule in the column stays constant
and the column warms... - ANSWER-It will become less dense and taller
All Together: Cold Air column.... - ANSWER-= low pressure aloft
= low (geopotential) height at constant pressure level
= upper-air trough
, All Together: Warm Air column.... - ANSWER-= high pressure aloft
= high (geopotential) height at constant pressure level
= upper-air ridge
Geostrophic Balance - ANSWER-Where the Coriolis force (COR) balances the pressure
gradient force (PGF) act in equal and opposite directions. (occurs when Geopotential
height contours are straight and friction can be ignored)
CF is - ANSWER-Coriolis Force
A warm column of air is associated with... - ANSWER-High pressure aloft
A cold column of air is associated with... - ANSWER-Low pressure aloft
Wind Barb - ANSWER-Wind barbs are used on weather maps to indicate the wind
speed and wind direction at a specific location
Isobars - ANSWER-Are lines connecting places of equal air pressure (at a fixed height)
Pressure Gradient - ANSWER-The spacing of the isobars indicates the amount of
pressure change over a given distance, which is known as the pressure gradient
Geopotential Height - ANSWER-Approximates the actual height of a pressure surface
above mean sea level
Geopotential Height Contours - ANSWER-Connect regions of the same geopotential
altitude of an isobaric (pressure) surface (lines of same height at a fixed pressure)
Troughs - ANSWER-In the geopotential height contours indicate regions of low heights
or low pressure and cold columns of air
Ridges - ANSWER-Indicate regions of high heights or high pressure and warm columns
of air
Other things to study... - ANSWER-- Jet stream directions
- Geostrophic Balance, the tale of wind
Centripetal Force - ANSWER-The inward directed net force that causes turning of air
flow around curved geopotential height contours due to the imbalance between the PGF
and the Coriolis force (always points inward)
High and low pressure at upper levels: Northern Hemisphere - ANSWER-- Winds blow
counter-clockwise around a low pressure system
-Winds blow clockwise around a high pressure system
COMPLETE SOLUTIONS
UTC Time Conversion: MDT (Zulu time) - ANSWER-MDT= UTC - 6 hours
UTC Time Conversion: MST (Zulu time) - ANSWER-MST= UTC - 7 hours
Wind - ANSWER-The horizontal movement of air due to horizontal differences in air
pressure
What causes wind? - ANSWER-Unequal heating of the Earth's surface, continually
creates differences in air pressure and results in wind
PGF - ANSWER-Pressure gradient force: the force due to differences in pressure within
the atmosphere that causes air to move and, hence, the wind to blow
Where does air flow in the PGF - ANSWER-High pressure to Low pressure
Forces - ANSWER-Newton's 1stLaw of Motion: an object at rest will remain at rest and
an object in motion will remain in motion (and travel at a constant velocity along a
straight line) as long as no force is exerted on the object
Equation for Force - ANSWER-F (net force) = m (mass) * a (acceleration)
Air Pressure - ANSWER-The pressure exerted by the weight of air above a given point
Sea Level Pressure - ANSWER-14 pounds of force over each square inch of our bodies
How does pressure change with altitude? - ANSWER-The pressure at any given altitude
is equal to the pressure exerted by weight of the air directly above that point, as we
move up through the atmosphere, the density of air decreases
Ideal Gas Law - ANSWER-Pressure = Temperature * Density * Constant
*Think about two air columns* If the number of molecule in the column stays constant
and the column cools... - ANSWER-It will become more dense and shorter
*Think about two air columns* If the number of molecule in the column stays constant
and the column warms... - ANSWER-It will become less dense and taller
All Together: Cold Air column.... - ANSWER-= low pressure aloft
= low (geopotential) height at constant pressure level
= upper-air trough
, All Together: Warm Air column.... - ANSWER-= high pressure aloft
= high (geopotential) height at constant pressure level
= upper-air ridge
Geostrophic Balance - ANSWER-Where the Coriolis force (COR) balances the pressure
gradient force (PGF) act in equal and opposite directions. (occurs when Geopotential
height contours are straight and friction can be ignored)
CF is - ANSWER-Coriolis Force
A warm column of air is associated with... - ANSWER-High pressure aloft
A cold column of air is associated with... - ANSWER-Low pressure aloft
Wind Barb - ANSWER-Wind barbs are used on weather maps to indicate the wind
speed and wind direction at a specific location
Isobars - ANSWER-Are lines connecting places of equal air pressure (at a fixed height)
Pressure Gradient - ANSWER-The spacing of the isobars indicates the amount of
pressure change over a given distance, which is known as the pressure gradient
Geopotential Height - ANSWER-Approximates the actual height of a pressure surface
above mean sea level
Geopotential Height Contours - ANSWER-Connect regions of the same geopotential
altitude of an isobaric (pressure) surface (lines of same height at a fixed pressure)
Troughs - ANSWER-In the geopotential height contours indicate regions of low heights
or low pressure and cold columns of air
Ridges - ANSWER-Indicate regions of high heights or high pressure and warm columns
of air
Other things to study... - ANSWER-- Jet stream directions
- Geostrophic Balance, the tale of wind
Centripetal Force - ANSWER-The inward directed net force that causes turning of air
flow around curved geopotential height contours due to the imbalance between the PGF
and the Coriolis force (always points inward)
High and low pressure at upper levels: Northern Hemisphere - ANSWER-- Winds blow
counter-clockwise around a low pressure system
-Winds blow clockwise around a high pressure system
