ATOC 1050 EXAM 2|| 96 QUESTIONS
AND ANSWERS 100% VERIFIED
Forces that control the movement of air - ANSWER-Pressure gradient Force
Gravitational Force
Frictional Force
Coriolis Force
Pressure Gradient - ANSWER-the rate at which pressure changes with distance
Air Parcel in the presence of a pressure gradient - ANSWER-will have a force applied to
it from high to low pressure
Pressure Gradient Force (PGF) - ANSWER-the force applied on an air parcel due to
pressure differences
On a surface weather map the PGF is always _______ to the isobars and points from
high to low pressure - ANSWER-Perpendicular
The PGF is _______ when the isobars are closely spaced - ANSWER-Large
Strong when contours are close together
The PGF is _____ when the isobars are spaced far apart. - ANSWER-Small
Weak where contours are far apart
The _____ _____ will increase as the horizontal pressure gradient, or horizontal PGF,
increases. - ANSWER-Wind Speed
Which direction is the vertical pressure gradient directed and why? - ANSWER-The
vertical pressure gradient is always directed upwards since pressure always decreases
with height
If the vertical pressure gradient is so strong, why doesn't the air just shoot off into
space? - ANSWER-Gravitational force opposes the vertical PGF
*The vertical PGF is balanced by gravity (almost always)!!*
Frictional Force - ANSWER-A drag force acting in a direction opposite the motion of the
air (i.e., it slows the wind down)
, When is friction strongest? - ANSWER-Closest to the surface of the Earth due to the
"roughness" of the Earth's surface
Mechanical Turbulence Cause - ANSWER-Air encounters obstructions on the surface;
Larger over a rough surface than over a smooth surface
Thermal Turbulence Cause - ANSWER-Heated air rises and mixes with the air above;
Most common during the day (surface heating)
Shear-Induced Turbuelnce - ANSWER-Seen when wind speed changes rapidly over a
short distance;
Largest when the wind shear is large
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Where is turbulence and the frictional force most important? - ANSWER-Tends to be
most important near the surface of the earth, and rapidly decreases as you move away
from the surface.
Turbulence, and thus the frictional force, rapidly ________ as you move away from the
surface. - ANSWER-Decreases
Friction Layer / Boundary Layer - ANSWER-the atmospheric layer in which friction is an
important force
How deep is the friction layer? - ANSWER-Varies from 100's to 1000's of meters.
Which situation would likely result in the highest atmospheric boundary layer (largest
amount of turbulence)? Why?
A. Nighttime over a frozen lake with no winds
B. Low winds over a corn field during the day
C. High winds over Boulder on a cold winter night
D. High winds over Boulder during a hot summer day
E. Low winds over Boulder during a hot spring day - ANSWER-D. High winds over
Boulder during a hot summer day
Heat creates a higher boundary layer
AND ANSWERS 100% VERIFIED
Forces that control the movement of air - ANSWER-Pressure gradient Force
Gravitational Force
Frictional Force
Coriolis Force
Pressure Gradient - ANSWER-the rate at which pressure changes with distance
Air Parcel in the presence of a pressure gradient - ANSWER-will have a force applied to
it from high to low pressure
Pressure Gradient Force (PGF) - ANSWER-the force applied on an air parcel due to
pressure differences
On a surface weather map the PGF is always _______ to the isobars and points from
high to low pressure - ANSWER-Perpendicular
The PGF is _______ when the isobars are closely spaced - ANSWER-Large
Strong when contours are close together
The PGF is _____ when the isobars are spaced far apart. - ANSWER-Small
Weak where contours are far apart
The _____ _____ will increase as the horizontal pressure gradient, or horizontal PGF,
increases. - ANSWER-Wind Speed
Which direction is the vertical pressure gradient directed and why? - ANSWER-The
vertical pressure gradient is always directed upwards since pressure always decreases
with height
If the vertical pressure gradient is so strong, why doesn't the air just shoot off into
space? - ANSWER-Gravitational force opposes the vertical PGF
*The vertical PGF is balanced by gravity (almost always)!!*
Frictional Force - ANSWER-A drag force acting in a direction opposite the motion of the
air (i.e., it slows the wind down)
, When is friction strongest? - ANSWER-Closest to the surface of the Earth due to the
"roughness" of the Earth's surface
Mechanical Turbulence Cause - ANSWER-Air encounters obstructions on the surface;
Larger over a rough surface than over a smooth surface
Thermal Turbulence Cause - ANSWER-Heated air rises and mixes with the air above;
Most common during the day (surface heating)
Shear-Induced Turbuelnce - ANSWER-Seen when wind speed changes rapidly over a
short distance;
Largest when the wind shear is large
⟶
⟶⟶⟶
⟶
Where is turbulence and the frictional force most important? - ANSWER-Tends to be
most important near the surface of the earth, and rapidly decreases as you move away
from the surface.
Turbulence, and thus the frictional force, rapidly ________ as you move away from the
surface. - ANSWER-Decreases
Friction Layer / Boundary Layer - ANSWER-the atmospheric layer in which friction is an
important force
How deep is the friction layer? - ANSWER-Varies from 100's to 1000's of meters.
Which situation would likely result in the highest atmospheric boundary layer (largest
amount of turbulence)? Why?
A. Nighttime over a frozen lake with no winds
B. Low winds over a corn field during the day
C. High winds over Boulder on a cold winter night
D. High winds over Boulder during a hot summer day
E. Low winds over Boulder during a hot spring day - ANSWER-D. High winds over
Boulder during a hot summer day
Heat creates a higher boundary layer
