CHAPTER 9
ATMOSPHERE’S PLANETARY CIRCULATION
______
MULTIPLE CHOICE QUESTIONS
1.Viewed from above in the Northern Hemisphere, surface winds about a subtropicalhigh blow
a.clockwise and inward.
b.counterclockwise.
c.counterclockwise and outward.
*d.clockwise and outward.
e.None of these is correct.
2.Viewed from above in the Southern Hemisphere, surface winds about a subtropical high blow
a.clockwise and inward.
b.counterclockwise.
*c.counterclockwise and outward.
d.clockwise and outward.
e.None of these is correct.
3.Dry climates characterize the ______flank of subtropical highs.
*a.eastern
b. western
c. equatorward
d. poleward
4.The western flank of a subtropical anticyclone is characterized by
a.relatively stable air.
b.mostly descending air.
*c.moist climates.
d.All of these are correct.
e.None of these is correct.
5.A broad region of light winds or calm air prevails
*a.along the horse latitudes.
b.near 60 degrees latitude.
c.along the Tropic of Capricorn.
d. in subpolar lows.
e. in the trade wind belts.
6. Subtropical anticyclones are ______-core circulation systems.
a. cold
*b. warm
7.Over a broad region about the center of a subtropical high, the horizontal air pressure gradient is relatively ______and winds are ______.
*a.weak...... light or calm
b.steep...... light or calm
c.weak...... strong
d.steep...... strong
e.None of these is correct.
8.The trade winds blow out of the ______flank of the subtropical anticyclones.
a.poleward
*b.equatorward
c.eastern
d.western
9.In the Northern Hemisphere, trade winds blow from the ______.
a.north
b.east
c.southeast
d.south
*e.northeast
10.In the Southern Hemisphere, trade winds blow from the ______.
a.north
b.east
*c.southeast
d.south
e.northeast
11.The global westerlies blow out of the ______flank of the subtropical anticyclones.
*a.poleward
b.equatorward
c.eastern
d.western
12. The tropical deserts of the world are found at latitudes near 30 degrees latitude because
a. the intertropical convergence zone occurs there.
b. of the doldrums.
c. of the sinking air associated with the polar front.
*d. of the sinking air associated with the subtropical highs.
13. Viewed from above in the Northern Hemisphere, winds above the atmospheric boundary layer blow ______about the center of a subtropical high.
*a. clockwise and parallel to isobars
b. clockwise and across isobars toward low pressure
c. counterclockwise and parallel to isobars
d. counterclockwise and across isobars toward high pressure
e. None of the above is correct.
14.Viewed from above, surface winds blow ______about the Icelandic low.
a.clockwise and outward
b.clockwise and inward
c.counterclockwise and outward
*d.counterclockwise and inward
15.The intertropical convergence zone (ITCZ) is usually located where Earth’s mean annual surface temperature ______.
a. is the lowest
*b. is the highest
c. varies drastically depending on the season
16.The trade winds of the two hemispheres
a.diverge at the equator.
b.are highly variable in speed and direction.
c.flow toward the east in a pattern of long-waves.
*d.are very persistent in direction.
e.None of the above is correct.
17.The ITCZ
a.is a discontinuous belt of cumulonimbus clouds.
b.marks the convergence of the trade winds of the two hemispheres.
c.is located near the equator on average.
d.is a discontinuous belt of thunderstorms.
*e.All of the above are correct.
18.A front is a narrow zone of transition between air masses that contrast in
a.temperature.
b.humidity.
c.density.
*d.Any of these is correct.
e.None of these is correct.
19.Hadley cells are located in ______latitudes of both hemispheres.
*a.tropical
b.middle
c.high
20.Hadley cells are
a.located in middle latitudes.
*b.similar to huge convection cells.
c.linked to the subpolar lows.
d.driven by the westerlies.
e.None of these is correct.
21. Hadley cell circulation causes air to ______in the ITCZ and ______in the subtropical anticyclones.
a. sink…..rise
*b. rise….sink
22.In the Northern Hemisphere, with the shift from winter to summer, the semi-permanent subtropical highs shift ______.
a.eastward
*b.northward
c.southward
d.westward
23.In the Northern Hemisphere, with the shift from summer to winter, the semi-permanent subtropical anticyclones shift ______.
a.eastward
b.northward
*c.southward
d.westward
24.In the Southern Hemisphere spring, the subtropical highs shift
a.eastward.
*b.poleward.
c.westward.
d.equatorward.
25.The middle latitude westerlies are ______energetic in winter than in summer.
a. less
b. equally as
*c. more
26. When viewed from above, subtropical gyres rotate in a ______direction in the Northern Hemisphere and in a ______direction in the Southern Hemisphere as a result of the Coriolis Effect.
*a. clockwise……counterclockwise
b. counterclockwise……clockwise.
c. both clockwise
d. both counterclockwise.
27.A monsoon circulation characterizes regions where seasonal reversals in prevailing winds cause ______summers and relatively ______winters.
*a. wet……dry
b. dry……wet
28.On a typical day, ______Rossby long-waves encircle the globe.
a.1 to 2
*b.2 to 5
c.3.5
d.dozens of
e.more than 100
29.Which one of the following westerly wave patterns favors the maximum north-south exchange of air masses?
a.zonal flow
*b.meridional flow
c.split flow
30.The westerly wave pattern that is likely to persist for the longest time is
a.zonal
*b.meridional
31.A blocking pressure system is associated with a ______flow pattern in the westerlies.
a.zonal
*b.meridional
32. Across the United States, temperature contrasts are generally greatest during a ______circulation pattern in the westerlies.
a. strong zonal
*b. strong meridional
c. weak meridional
d. weak zonal
33. In the Midwest, drought is most likely with a ______circulation pattern in the westerlies.
a. strong zonal
b. split-flow
c. weak meridional
*d. blocking
34. Narrow corridors of very strong winds within the atmosphere are known as
a. short waves
b. Rossby waves
*c. jet streams
35. Horizontal divergence occurs to the ______of an upper-air trough.
*a. east
b. north
c. west
d. south
36. Horizontal convergence occurs to the ______of an upper-air ridge.
*a. east
b. north
c. west
d. south
37. Horizontal divergence occurs to the ______of an upper-air ridge.
a. east
b. north
*c. west
d. south
38. Horizontal convergence occurs to the ______of an upper-air trough.
a. east
b. north
*c. west
d. south
39. A synoptic-scale cyclone is most likely to develop on the ______side of an upper-air trough.
*a. east
b. north
c. west
d. south
40. A synoptic-scale cyclone is most likely to develop on the ______side of an upper-air ridge.
a. east
b. north
*c. west
d. south
41. In an essentially straight jet streak viewed from above, the strongest horizontal divergence takes place in the ______quadrant.
a. left rear
b. right rear
*c. left front
d. right front
42.The polar front jet stream is usually located in southern Canada in
*a.summer
b. winter
43. The Southern Oscillation
a. was discovered by Sir Gilbert Walker early in the 20th century.
b. is a seasaw variation in air pressure across the tropical Indian and PacificOceans.
c. is linked to the development of El Niño.
*d. All of these are correct.
e. None of these is correct.
44. In the Northern Hemisphere, Ekman transport of surface ocean waters is about ______the surface wind direction.
a. 45 degrees to the left of .
b. 90 degrees to the left of
*c. 90 degrees to the right of
d. 30 degrees to the right of
45.Upwelling
a.brings cold bottom water to the ocean surface.
b.is the long-term average condition off the northwest coast of South America.
c.is suppressed during El Niño.
d.supports important fisheries.
*e.All of the above are correct.
46. El Niño can be described as the ______phase of the Southern Oscillation, and La Niña the ______phase.
*a. warm…...cold
b. cold…….warm
47.An extreme and persistent El Niño
a.can be expected every year in mid-December.
*b.may be accompanied by weather extremes in various parts of the world.
c.involves an interaction between the tropical Atlantic ocean and atmosphere.
d.seldom lasts longer than a few weeks.
48.During “neutral” conditions, sea surface temperatures are highest in the ______tropical Pacific.
*a.western
b.central
c.eastern
49. In the ENSO Alert System, an El Niño or La Niña ______is issued when El Niño or La Niña conditions have developed and are expected to continue.
a. watch
*b. advisory
c. warning
50. The ENSO Observing system consists of
a. island and coastal tide gauges.
b. satellites.
c. an array of instrumented buoys.
d. ship-based instruments.
*e. All of the above are correct.