<p>CHAPTER 9</p><p>ATMOSPHERE’S PLANETARY CIRCULATION ______</p><p>MULTIPLE CHOICE QUESTIONS</p><p>1. Viewed from above in the Northern 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.</p><p>*d. clockwise and outward.</p><p>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.</p><p>*c. counterclockwise and outward.</p><p>3. 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.</p><p>*a. clockwise and parallel to isobars</p><p>4. The eastern flank of a subtropical anticyclone is characterized by a. unstable air. b. ascending air. c. dry climates. d. All of these are correct. e. None of these is correct.</p><p>*c. dry climates.</p><p>5. 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.</p><p>*c. moist climates.</p><p>6. A broad region of very light winds or calm conditions prevail a. in subpolar lows. b. in the trade wind belts. c. along the horse latitudes. d. near 60 degrees latitude. e. at the Tropic of Cancer.</p><p>*c. along the horse latitudes.</p><p>7. Subtropical anticyclones are ______-core systems. a. cold b. warm</p><p>*b. warm</p><p>8. Over a broad region about the center of a subtropical high, the horizontal air pressure gradient is ______and winds are ______. a. weak...... calm b. steep...... calm c. weak...... strong d. steep...... strong e. None of these is correct.</p><p>*a. weak...... calm</p><p>9. The trade winds blow out of the ______flank of the subtropical anticyclones. a. poleward b. equatorward c. eastern d. western</p><p>*b. equatorward</p><p>10. In the Northern Hemisphere, trade winds blow from the ______. a. north b. east c. southeast d. south e. northeast</p><p>*e. northeast</p><p>11. In the Southern Hemisphere, trade winds blow from the ______. a. north b. east c. southeast d. south e. northeast</p><p>*c. southeast</p><p>12. The global westerlies blow out of the ______flank of the subtropical anticyclones. a. poleward b. equatorward c. eastern d. western</p><p>*a. poleward</p><p>13. 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</p><p>*d. counterclockwise and inward</p><p>14. The trade winds of the two hemispheres converge in the a. subpolar lows. b. ITCZ. c. polar highs. d. subtropical highs. e. None of these is correct.</p><p>*b. ITCZ.</p><p>15. 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.</p><p>*d. are very persistent in direction. 16. The intertropical convergence zone (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.</p><p>*e. All of the above are correct.</p><p>17. 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.</p><p>*d. Any of these is correct.</p><p>18. Hadley cells are located in ______latitudes of both hemispheres. a. tropical b. middle c. high</p><p>*a. tropical</p><p>19. Hadley cells are a. located in midlatitudes. b. similar to huge convection cells. c. linked to the subpolar lows. d. driven by the westerlies. e. None of these is correct.</p><p>*b. similar to huge convection cells.</p><p>20. In the Northern Hemisphere, when the seasons shift from winter to summer, the semipermanent subtropical highs shift ______. a. eastward b. northward c. southward d. westward</p><p>*b. northward</p><p>21. In the Northern Hemisphere, when the seasons shift from summer to winter, the semipermanent subtropical anticyclones shift ______. a. eastward b. northward c. southward d. westward</p><p>*c. southward</p><p>22. In the Northern Hemisphere autumn, the ITCZ shifts a. eastward. b. poleward. c. westward. d. equatorward.</p><p>*d. equatorward.</p><p>23. In the Southern Hemisphere spring, the subtropical highs shift a. eastward. b. poleward. c. westward. d. equatorward.</p><p>*b. poleward.</p><p>24. The midlatitude westerlies are more energetic in ______than in ______. a. winter...... summer b. summer...... winter</p><p>*a. winter...... summer</p><p>25. Long-waves in the westerlies undergo changes in a. wavelength. b. number of waves. c. wave amplitude. d. All of these are correct.</p><p>*d. All of these are correct.</p><p>26. 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</p><p>*b. 2 to 5 27. 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</p><p>*b. meridional flow</p><p>28. The westerly wave pattern that is likely to persist for the longest time is a. zonal b. meridional</p><p>*b. meridional</p><p>29. A blocking pressure system is associated with a ______flow pattern in the westerlies. a. zonal b. meridional</p><p>*b. meridional</p><p>30. The average winter location of the polar front jet stream is a. southern Canada. b. Iceland. c. southern United States. d. northern Canada. e. Mexico.</p><p>*c. southern United States.</p><p>31. The average summer location of the polar front jet stream is a. southern Canada. b. Iceland. c. southern United States. d. northern Canada. e. Mexico.</p><p>*a. southern Canada.</p><p>32. Viewed from above an essentially straight jet streak, the strongest horizontal divergence takes place in the ______quadrant. a. left rear b. right rear c. left front d. right front</p><p>*c. left front 33. Horizontal divergence occurs to the ______of an upper-air trough. a. east b. north c. west d. south</p><p>*a. east</p><p>34. Horizontal convergence occurs to the ______of an upper-air ridge. a. east b. north c. west d. south</p><p>*a. east</p><p>35. Horizontal divergence occurs to the ______of an upper-air ridge. a. east b. north c. west d. south</p><p>*c. west</p><p>36. Horizontal convergence occurs to the ______of an upper-air trough. a. east b. north c. west d. south</p><p>*c. west</p><p>37. 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</p><p>*a. east</p><p>38. 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</p><p>*c. west</p><p>39. 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</p><p>*d. blocking</p><p>40. 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</p><p>*b. strong meridional</p><p>41. During droughts, when soil moisture is low, the Bowen ratio is relatively a. low b. high</p><p>*b. high</p><p>42. 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.</p><p>*e. All of the above are correct.</p><p>43. 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.</p><p>*b. may be accompanied by weather extremes in various parts of the world.</p><p>44. The intertropical convergence zone (ITCZ) is a. also known as the horse latitudes. b. an area of clear skies where the trade winds meet the midlatitude westerlies. c. the sinking portion of the Hadley cells. d. the persistent band of cloudiness near the equator.</p><p>*d. the persistent band of cloudiness near the equator.</p><p>45. The tropical deserts of the world are found at latitudes near 30o 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.</p><p>*d. of the sinking air associated with the subtropical highs.</p><p>46. The Bermuda high is a. located on average about 30 degrees N latitude over the Atlantic Ocean. b. caused by the rising air in the Hadley cell. c. the spawning ground for hurricanes in the Atlantic Ocean. d. associated with the development of El Niño.</p><p>*a. located on average about 30 degrees N latitude over the Atlantic Ocean.</p><p>47. The Icelandic low a. is a type of fish caught in the North Atlantic Ocean. b. is caused by the sinking air in the Hadley cell. c. is located on average about 60 degrees N latitude over the North Atlantic. d. completely disappears in summer.</p><p>*c. is located on average about 60 degrees N latitude over the North Atlantic.</p><p>48. If you travel to Honolulu, Hawaii (latitude 21 degrees N), you would most likely experience winds blowing from the a. northeast b. southwest c. west d. northwest</p><p>*a. northeast</p><p>49. Chicago, IL (latitude 42 degrees N) is located in the wind belt known as the ______. a. northeast trades b. southeast trades c. polar easterlies d. westerlies</p><p>*d. westerlies 50. La Niña ______follows El Niño. a. sometimes b. always</p><p>*a. sometimes</p>