Download This exam covers Ahrens Chapters 7, 8, 10, and 12, plus related

AT 350
EXAM #3
April 29, 2008
This exam covers Ahrens Chapters 7, 8, 10, and 12, plus related lecture notes
Write the letter of the choice that best completes the statement or answers the question.
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1. The merging of liquid cloud droplets by collision is called:
a. coalescence
b. riming
c. accretion
d. deposition
2. The amount of pressure change that occurs over a given horizontal distance is called the:
a. pressure tendency
b. Coriolis parameter
c. pressure gradient
d. potential gradient
e. slope
3. Which of the following forces can not act to change the speed of the wind?
a. pressure gradient force
b. frictional force
c. Coriolis force
d. none of the above
4. In terms of the three-cell model of the general circulation, areas of surface low pressure should be found at:
a. the equator and the poles
b. the equator and 30o latitude
c. the equator and 60o latitude
d. 30o latitude and 60o latitude
e. 30o latitude and the poles
5. The wind around a surface high pressure center in the Northern Hemisphere blows:
a. counterclockwise and outward from the center
b. counterclockwise and inward toward the center
c. clockwise and outward from the center
d. clockwise and inward toward the center
6. Which of the following produces the strongest Coriolis force?
a. fast winds, low latitude
b. fast winds, high latitude
c. slow winds, low latitude
d. slow winds, high latitude
7. The force that would cause a stationary parcel of air to begin to move horizontally is called the:
a. Coriolis force
b. pressure gradient force
c. centripetal force
d. frictional force
8. On a weather map of the Northern Hemisphere, one would observe the westerlies:
a. north of the subpolar lows
b. south of the tropical highs
c. between the doldrums and the horse latitudes
d. between the subpolar lows and the subtropical highs
Exam form A
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AT 350
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EXAM #3
April 29, 2008
9. In winter, which sequence of clouds would you most likely expect to observe as a warm front with
precipitation approaches your location?
a. cirrus, nimbostratus, altostratus, cumulonimbus
b. cirrus, cirrostratus, altostratus, nimbostratus
c. cirrostratus, nimbostratus, altostratus, fog
d. cirrus, cirrostratus, altostratus, cumulonimbus
10. Net convergence of air would cause surface pressure to __________ and net divergence would
cause surface pressure to __________.
a. increase, decrease
b. increase, increase
c. decrease, decrease
d. decrease, increase
11. Supercooled cloud droplets are:
a. ice crystals surrounded by air warmer than 0 oC (32 oF)
b. liquid droplets that are cooler than the air around them
c. liquid droplets observed at temperatures below 0 oC (32 oF)
d. water droplets that have had all their latent heat removed
12. The wind's speed generally increases with height above the earth's surface because:
a. only the lowest layer of air rotates with the earth
b. air temperature normally decreases with height
c. wind instruments are not accurate at the earth's surface
d. friction with the earth's surface slows the air near the ground
e. air parcels expand and become less dense as they rise above the surface
13. During the Bergeron ice crystal process of rain formation:
a. only ice crystals need be present in a cloud
b. ice crystals grow larger at the expense of the surrounding liquid cloud droplets
c. the temperature in the cloud must be -40o C (-40o F) or below
d. the cloud must be a cumuliform cloud
14. If the earth's gravitational force were to increase, atmospheric pressure at the ground would:
a. increase
b. decrease
c. remain the same
d. cause the atmosphere to expand vertically
15. In Honolulu, Hawaii (latitude 21o N), you would most likely experience winds blowing from the:
a. northeast
b. south
c. southwest
d. northwest
16. At the same sub-freezing temperature, the saturation vapor pressure just above a liquid water surface is
_________ the saturation vapor pressure above an ice surface.
a. greater than
b. the same as
c. less than
17. When comparing an "average" cold front to an "average" warm front, which of the following is not correct?
a. generally, cold fronts move faster than warm fronts
b. generally, cold fronts have steeper slopes
c. generally, precipitation covers a much broader area with a cold front
d. especially in winter, cumuliform clouds are more often associated with cold fronts
Exam form A
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AT 350
EXAM #3
April 29, 2008
_E__ 18. Generally, along the polar front one would not expect to observe:
a. temperatures on one side lower than on the other side
b. an elongated region of lower pressure
c. clouds and precipitation
d. converging surface air
e. sinking air aloft
__A_ 19. In the Northern Hemisphere, the polar jet stream is strongest when:
a. air north of the polar front is much colder than air south of the polar front
b. air north of the polar front is much warmer than air south of the polar front
c. air temperatures on opposite sides of the polar front are about equal
d. air temperatures on the East Coast of the US are much colder than on the West Coast of
the US
__B_ 20. Which of the following is not correct concerning a warm front?
a. it is colored red on a weather map
b. it has warm air ahead (in advance) of it
c. in winter it is usually associated with stratiform clouds
d. it normally moves more slowly than a cold front
_D__ 21. The world's deserts are found near 30o latitude because:
a. the intertropical convergence zone is located there
b. of the sinking air of the polar front
c. of the convergence of the prevailing westerlies and the Northeast Trades
d. of the sinking air of the subtropical highs
e. of the doldrums
_D _ 22. In the polar front theory of a developing wave cyclone, energy for the storm is usually derived
from all but one of the following:
a. rising of warm air and the sinking of cold air
b. latent heat of condensation
c. an increase in surface winds
d. heat energy stored in the ground
__B_ 23. During a warm El Nino event
a. coastal upwelling along the US west coast becomes more intense
b. drought is common in Indonesia and northeastern Brazil
c. Huge snowfall always occurs in Colorado
d. intensified rising motion occurs over the tropical west Pacific Ocean
__E_ 24. Surface divergence in a midlatitude cyclone is associated with
a. upward motion around the surface low
b. anticyclonic flow around a surface high pressure center
c. low clouds and light precipitation
d. downward motion and sunny weather
e. both b and d
_E__ 25. During normal (non El Nino) conditions,
a. sea-surface temperatures in the tropical east Pacific are cooler than in the west
b. surface pressure in the west Pacific is higher than in the east
c. trade wind flow above the tropical Pacific is stronger than during warm El Nino events
d. both b and c
e. both a and c
Exam form A
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EXAM #3
April 29, 2008
_D__ 26. The energy that produces a midlatitude cyclone is derived from
a. solar heating exceeding longwave radiative cooling in the tropics
b. longwave cooling exceeding shortwave heating in polar regions
c. juxtaposition of warm and cold air masses near the surface
d. oversteepening of upper-level pressure surfaces and associated intense westerlies
e. all of the above
__E_ 28. Strong upward motion in a midlatitude cyclone can be found
a. ahead of the cold front
b. around the surface low
c. due to overrunning air above the warm front
d. in convective (cumulus) clouds
e. all of the above
_E__ 28. Anticyclonic surface winds associated with subtropical high pressure systems
a. are associated with abundant precipitation and clouds
b. cause surface convergence of Ekman transport in the oceans
c. cause surface divergence of Ekman transport in the oceans
d. are associated with regions of ocean downwelling
e. both b and d
__B_ 29. A midlatitude cyclone may intensify due to baroclinic instability when
a. surface air becomes buoyant due to radiative heating
b. high and low pressure zones tilt to the west with height
c. an upper-level trough passes over a surface low pressure center
d. latent heating in convective clouds reaches the 200 mb level
__A_ 30. For cyclogenesis to occur along a frontal wave, the winds aloft directly above the wave should be:
a. diverging
b. converging
c. blowing straight from west to east
d. increasing in speed uniformly over a broad area
_B__ 31. Near-surface ocean currents in middle latitudes generally move
a. in the same direction as the wind
b. to the right of the direction of the wind in the Northern Hemisphere
c. to the left of the direction of the wind in the Northern Hemisphere
d. opposite to the direction of the wind
_A__ 32. The Ekman Spiral describes:
a. the turning of water with depth
b. the air flow into a center of low pressure
c. the circulation of surface water around a gyre
d. the air flow out of a region of high pressure
e. the wind-flow pattern in a jet stream
_A __ 33. An upper-level pool of cold air that has broken away from the main flow is called:
a. a cut-off low
b. a shortwave
c. a wave cyclone
d. a lee-side low
_A__ 34. A building anticyclone means:
a. the central pressure is increasing
b. the anticyclone is moving toward the east coast
c. separate anticyclones are merging
d. the anticyclone is causing a middle latitude storm to form
Exam form A
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AT 350
EXAM #3
April 29, 2008
_A__ 35. Cyclogenesis is the ___________ of a mid-latitude cyclone.
a. development or strengthening
b. weakening or dissipation
c. term for the exact midpoint
d. none of the above
__C_ 36. Cold-air advection can intensify a midlatitude cyclone when
a. poleward flow west of the surface low undermines the upper-level ridge
b. it displaces warm air to the east of the surface low
c. equatorward flow west of the surface low deepens the upper-level trough
d. thunderstorms are in the vicinity
e. all of the above
_D__ 37. Major ocean current systems in middle latitudes of both hemispheres
a. rotate as "gyres" in the opposite sense of the rotation of the Earth
b. accomplish as much as 40% of the required poleward heat transport
c. are driven indirectly by the wind
d. all of the above
_C__ 38. When upper-level divergence of air above a surface low pressure area is stronger than the convergence of
surface air, the surface pressure will __________ and the storm itself will __________.
a. increase, intensify
b. increase, dissipate
c. decrease, intensify
d. decrease, dissipate
__C_ 39. Which of the following is not associated with rising air motions?
a. overrunning
b. convergence of air at the surface
c. convergence of air aloft
d. divergence of air aloft
_B__ 40. The large thermally driven convection cell that is driven by convective "hot" towers along the equator is the:
a. Ferrel cell
b. Hadley cell
c. Ekman spiral
d. El Niño cell
__B_ 41. A condition where the central and eastern tropical Pacific Ocean turns cooler than normal is called:
a. El Niño
b. La Niña
c. the Southern Oscillation
d. the Ekman Spiral
_C__ 42. Although the polar regions radiate away more heat energy than they receive by insolation in the course of a
year, they are prevented from becoming progressively colder each year by the:
a. conduction of heat through the interior of the earth
b. concentration of earth's magnetic field lines at the poles
c. circulation of heat by the atmosphere and oceans
d. the insulating properties of snow
e. release of latent heat to the atmosphere when polar ice melts
__D_ 43. A wind that blows at a constant speed parallel to curved isobars or contour lines is called a:
a. geostrophic wind
b. cyclonic wind
c. convergent wind
d. gradient wind
Exam form A
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