Homework Questions #2: Answers
1. What is the definition of temperature?
The measure of the average kinetic energy (speed of the molecules) of a substance
2. Atmospheric pressure is the _______weight of the column of air ______
above you.
3. a) What is the name of the atmospheric layer where all weather occurs?
Troposphere
b) Does temperature increase or decrease as you go up in this layer?
Decrease
c) Does atmospheric pressure increase or decrease as you go up in this layer?
Decrease
4. a) What is the name of the layer above the “weather” layer?
Stratosphere
b) Does temperature increase or decrease as you go up in this layer? Why?
Increases due to the presence of ozone, which absorbs ultraviolet radiation from
the sun
c) Does atmospheric pressure increase or decrease as you go up in this layer?
Decrease
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5. What is the transition between the “weather” layer and the layer above called?
Tropopause
6. Which is lighter (less dense) moist air or dry air?
Moist air
7. Which is lighter (less dense) warm air or cold air?
Warm air
8. Wind direction is the direction_____from which the wind is blowing________.
9. Rawinsondes (“weather baloons”) provide information on ____the vertical structure
of the atmosphere (troposphere and stratosphere________________ for weather
analysis and computer modeling for weather forecasting.
10. Radar is utilized to identify _____the location and intensity of precipitation______.
11. Doppler radar is useful for identifying ___rotating thunderstorms and tornadoes__.
12. a) What type of satellite is only useful during the day?
Visible satellite
b) Which type of satellite essentially measures the temperature of visualized
objects and can be used at all times, day and night?
Infrared satellite
13. Lines (contours) of equal pressure drawn on a weather map are called
______isobars_________.
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14. What type of atmospheric motion “causes” weather?
Vertical (up and down) motion
15. Rising air causes ________stormy_______ weather and sinking air causes
_________clear________ weather.
16. As air rises it _______cools_______ so that water vapor eventually
________condenses into liquid droplets_________, forming _____clouds_____.
17. What is the characteristic of water that makes it a unique element on earth and
also why it plays such an important role in extreme weather?
It is the one element on earth that can change phase at temperatures normally
encountered in our environment
18. Saturation vapor pressure (SVP) measures ___air’s capacity for water vapor
molecules (the amount of water vapor that air can “hold”)_____.
19. SVP is determined solely by ________air temperature__________.
20. Relative humidity (vapor pressure/SVP) measures how close the air is to being
________saturated_______________.
21. Dewpoint temperature is the temperature you would need to cool the air down to
for _________saturation to occur (dew or clouds will form with further cooling)____.
It is also a measure of the _______absolute amount of water vapor______in the air.
22. When cloud formation occurs there is a release of ______latent heat____,
which provides the energy for some types of extreme weather.
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23. What are the three general causes of vertical motion in the atmosphere?
Mechanical (physical) lifting, force imbalances, convection
24. What force generates the wind and determines how fast it will blow?
Pressure gradient force
25. Coriolis force is an ______apparent (not real)_______ force that exists due to
____earth’s spherical shape and rotation_________.
26. Coriolis force only changes ______the direction of motion of air (wind direction)
not its _____speed______.
27. What are the two forces that are generally in balance (in a horizontal plane;
called geostrophic balance) above earth’s surface?
Pressure gradient force and Coriolis force
28. Because of this balance (#60) wind flows ____counter-clockwise___ around low
pressure systems (cyclones) and ________clockwise________ around high
pressure systems (anticyclones).
29. What is a jet stream?
A relatively narrow band of strong horizontal winds that encircles the earth at
upper portions of the troposphere in midlatitudes
30. At what level of the atmosphere are the winds in a jet stream the strongest?
At or just below the tropopause
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31. What type of “gradient” between the tropics and the poles results in the pressure
differences that creates jet streams and determines how strong the winds in them
will be?
Temperature gradient
32. Which type of extreme weather, extratropical cyclones or tropical cyclones
(hurricanes) are associated with jet streams?
Extratropical cyclones
33. _________Divergence________ at the tropopause results in removal of air from
the atmospheric column leading to upward motion in the troposphere and
eventual development of surface low pressure.
34. What two jet stream flow features are associated with this process (#33)?
Curved flow (curvature) and jet streaks
35. Where, relative to a “trough” in the jet stream, is a surface low pressure system
most likely to develop. (Identify this location in a wave diagram like the one I
drew in class)
↑ North
A
D
B
C
↓ South
Most likely to develop to the east of the “trough”. This would be “D” in the
diagram
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36. a) What is the additional force, only present to a significant degree at earth’s
surface, that results in convergence into a surface low pressure system to
complete the vertical circulation associated with these systems?
Friction
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