Mteor 206                                            Final Exam                                       April 1998

Test 2

 

26.  Jet streams

a.                    are strongest near the equator

b.                    blow east to west during winter and west to east during the summer season

c.         are fastest where horizontal temperature changes are greatest

d.         all of the above

 

27.  Warm air rises and cold air sinks in a direct circulation (e.g., a sea breeze or a land breeze) but in these circulations winds blow horizontally also because:

a.          a pressure gradient exists

b.                      the warm region “pulls” in the cold air

c.                      the cold region “pulls” in the warm air

d.                      the Coriolis force always causes wind to blow if you are not on the equator

 

28. An air mass is a very large body of air

a.       which has the same temperature from the surface to nearly 500 mb

b.      which has precipitation only at the edges

      c.   with nearly uniform temperature and moisture conditions at any altitudes

d.   which has high pressure at the center and low pressure at the edges

 

 

29.  A parameter which influences both weather and climate is ______.

a.                    variation of sun with latitude

b.                    land/water distribution

c.          positions of semi-permanent high and low pressure areas

d.         all of the above

 

30.  In a 3-cell circulation model the highs are located at ______ and the lows at ____

a.                    60, 30

b.         30, 60

c.          0, 60

d.         60, 0

 

31.  The doldrums are regions of weak winds which

a.        exist near the equator because pressure gradients are weak there

b.        exist near 30o N latitude because this is a region of frequent high pressure areas

c.        exist along ancient sea routes where winds blew opposite to persistent ocean currents

d.       can exist anywhere depending on the existence of an “extensive” closed high pressure

 

32.  The prevailing surface winds for the earth are determined from

a.                    the cell circulation and the pressure gradient force

b.         the cell circulation and the Coriolis effect

c.         land-sea temperature contrasts

d.         horizontal winds which occur because the earth rotates and their interaction with the major mountain systems

 

33.  The major deserts on the earth are mainly located near:

a.          30oN, 30oS

b.          45oN, 45oS

c.           30oN, equator

d.              30oS, 45oS

 

34.  Chinook winds are warm dry winds that descend the east slope of the Rocky  Mountains.  These winds are warm as a results of

a.                    excessive heating during cloud-free periods

b.                      the solar rays which are more perpendicular to the mountain slopes compared with the plains

c.                    wet adiabatic heating during descent

d.         dry adiabtic heating during descent

 

35.  The intertropical convergence zone

a.                    follows the sun

b.                    is where the SE and NE trade winds meet

c.                    is a region of persistent convective activity

d.         all of the above

 

36.  Along the west coast of the U.S. the prevailing winds are from N to S.  Which of the following is responsible for upwelling of cold water?

a.                     El Niño

b.         Coriolis force

c.          Santa Ana winds

a.                    all of the above

 

37. An occluded front forms when _____

  1. a warm front overtakes a slower moving cold front
  2. a cold front overtakes a slower moving warm front
  3. a stationary front begins to move in response to changes in upper level air flow patterns
  4. a warm, moist unstable air mass is convectively stirred

 

38.   During non- El Niño years

a.                  upwelling of cool water occurs all along the equator

b.                  normal weather occurs everywhere

c.                  winds blow toward Ecuador causing upwelling and good fishing

d.        winds blow from high to low pressure and push water westward toward  Australia

 

39.  During El Niño periods the low pressure system near Indonesia moves _______ and the high pressure over the eastern Pacific ________causing the NE, SE trade winds to weaken.

a.      westward, weakens

b.      eastward, weakens

c.      westward, strengthens

d.      eastward, strengthens

 

40.  Pressure differences between Darwin and Tahiti can be used to identify

        a.  an El Niño period

        b.  the on-set of the hurricane season

              c.  the position of the ITCZ

d.  all of the above

 

41. A Hadley-type circulation is associated with

a.                    warm air rising, cold air sinking

b.                    a direct circulation

c.                    0-30o of latitude

d.        all of the above

 

42.  Short waves frequently move through long wave patterns.  These short waves can initiate

  1. zonal winds
  2. frictional forcing
  3. temperature advection
  4. Helmholtz instability

 

43. Which of the following is NOT an air mass source region

a.      Gulf of Mexico

b.      Ice/snow covered Arctic plains

c.      east Pacific ocean

d.      Rocky Mountains

 

44.  Severe weather systems are a small percentage of all weather systems because

  1. the essential alignment of upper air and surface weather patterns is rarely realized
  2. the flow of warm moist air from the Gulf of Mexico happens infrequently
  3. the prevailing westerlies usually move the cA air mass too far east to interact with gulf flow
  4. jet stream winds almost always “blow the top” off major storm systems

 

 

45. The most basic reason weather occurs is

  1.  to moderate the temperature imbalance between the equator and the poles
  2. to convert water vapor to precipitation
  3. a result of interactions of prevailing winds with land and ocean areas
  4. a consequence of the rotation of the earth about its axis

 

 

46. The two air mass types which most frequently interact in the central plains are:

      a.  cP, mT

            b.  mP, cA

c.  mP, cA

            d.  cT, mT

 

 

 

 

47. Air masses can change as they move over different surfaces.  When a mP air mass moves eastward over the mountains it can become:

a.      mT

b.      cT

            c.  cP

            d.  all of the above

 

48. Characteristics of cT air mass are:

a.      hot dry

b.      clear skies

c.      can lead to severe droughts

d.      all of the above

 

49. A “front” occurs

            a.  at the intersection of two different air masses

            b.  midway between a high and low pressure centers

            c.  directly under a 500 mb trough

e.      all of the above

 

50.  A front may be located by

a.      a distinct temperature change over a short distance

b.      a distinct dew point temperature change over a short distance

c.      observed changes in wind direction over a short distance

d.      all of the above

 

51.  The slope of the frontal surface associated with warm fronts is _____ the slope of the frontal surface associated with cold fronts.

a.      more vertical than

b.      less vertical than

c.      similar to

 

52.   Where cold surface air is replacing warm air, the boundary separating the different masses of air is termed ______.

a.      a cold front

b.      a warm front

c.      a stationary front

d.      an occluded front

 

53.  A local radio station reported that a rain-producing weather front was about 3 hours away and headed in our direction, but the local sky was presently clear and sunny.  The approaching weather front must be _______ front

  1. an occluded
  2. a stationary
  3. a warm
  4. a cold

 

 

 

 

 

54. Precipitation patterns within the latitude band 10oN and 10oS are

  1. always tropical and thus wet all year
  2. highly seasonal because the ITCZ follows the sun
  3. tropical except in desert regions
  4. tropical except on the downwind side of mountains

 

 

55.  When we compare the satellite images of cloud in the midlatitudes with those at the equator we find

a.                    they look nearly the same everywhere but are more numerous at the equator

b.                    clouds are less numerous at the equator

c.         cloud systems are comma-like in the midlatitudes, more “clumped” near the      equator

d.        during the “summer” season midlatitude and equatorial clouds are similar but during the “winter” season the midlatitude clouds change to layers

 

56.  The most devastating aspect of a hurricane is the

  1. flooding associated with the heavy rains
  2. debris blown about by the high winds
  3. flooding and waves associated with the storm surge
  4. increasing strength of the system as it leaves the water and moves across land

 

57. West coasts of continents are ______ than east coasts because ______

  1.  drier, semi-permanent high pressure systems cause cool water near the coast which increases atmospheric stability
  2. drier, prevailing winds interact with the mountains to cause a rain shadow
  3. wetter, prevailing winds interact with the mountains which results in upslope precipitation
  4. wetter, prevailing west to east winds have abundant moisture as they move on-shore

 

58. If an upper level low is directly above a surface low we would expect the

  1. surface low to deepen
  2. surface low to maintain its strength
  3. surface low to fill
  4. upper level low to deepen

 

59. ________ at upper levels above a surface high pressure region will cause it to intensify.

  1. Divergence
  2. Convergence
  3. An occlusion
  4. Conversion of potential to kinetic energy

 

60. Baroclinic regions occur when _____ and _____ cross to cause ______.

  1. cold fronts, warm fronts, lifting
  2. cold fronts, cool fronts, lifting
  3. winds, isobars, precipitation
  4. isobars, isotherms, advection

 

61. Ordinary thunderstorms have a lifetime of about _____ hour(s) because updrafts are wiped out by ________.

  1. 2, shear
  2. 2, storm electrification
  3. ½, precipitation
  4. ½, outflow processes

 

62. The flicker of a lightning stroke occurs because

  1. uneven rainfall rates obscure the actual stroke
  2. multiple return strokes are common
  3. the lightning channel actually rotates slowly
  4. ambient winds cause the stroke to oscillate

 

63. Lightning paths are “attracted” to isolated objects such as people on a golf course, farmers on tractors, and trees, because

  1. they are essentially fixed in space
  2. they retain induction charging longer than objects with lower profiles
  3. electric field lines are compressed around these vertical objects
  4. all of the above

 

64. While in Honolulu, Hawaii (latitude 21 N) you would most likely experience winds blowing from the ______

  1. northeast
  2. south
  3. southwest
  4. west

 

65. Hurricanes and tropical cyclones do NOT form __________

  1. in the Indian Ocean
  2. in the Pacific Ocean
  3. in the Atlantic Ocean
  4. on the equator

 

66. Outflow at the top of the huge convective storms in the eye wall of the hurricane _______ into the center of the system, resulting in _______ moving air in the eye.

  1. converges, upward
  2. converges, downward
  3. swirls, counterclockwise
  4. swirls, clockwise

 

67. The energy which drives a hurricane comes from

  1. a deep, very warm layer of water
  2. Coriolis forces at the equator
  3. extremely tight pressure gradients which form near the equator
  4. latent heat released in the ITCZ

 

 

 

 

68. Ozone decreases have significantly impacted skin cancer incidences

  1. only in the Antarctic
  2. only at either polar region
  3. only midlatitudes of the southern hemisphere
  4. even in northern hemisphere latitudes which includes Ames, Iowa (this is the right answer!)

 

69. Global climate variations with large peaks and valleys have been documented for at least 800,000 years. ______was the scientist who explained these dramatic changes were due to orbital variations and differences in the tilt of the earth’s axis.

  1. Keppler
  2. Newton
  3. Milankovitch
  4. Galileo

 

70.  As a wave cyclone develops

      a.  potential energy is converted to kinetic energy

      b.  the faster moving cold front squeezes in on the warm front

      c.  the isobars surrounding the low pressure center become more closely packed

      d.  all of the above