9-8. 



According to the 3-cell theory, in what 

 vertical direction does air move at lati 

 tudes of 0°, 30°, 60°, and 90° in the 

 Northern Hemisphere? 



1. Down at 0° and 60 



2. Down at 30° and 60 



3. Down at 30° and 90 



Down at 60° and 90°; up at 



up at 30° and 90° 



up at 0° and 90° 



0° and 60° 



0° and 30° 



up at 



In items 9-9 through 9-11, select from column B 

 the general direction of airflow in each North- 

 ern Hemisphere circulation cell listed in 

 column A. 



A. Circulation B. Airflow Directions 



9-9. Tropical 

 9-10. Midlatitude 

 9-11. Polar 



1. Poleward at the sur- 

 face, equatorward 

 aloft 



2. Poleward aloft, 

 equatorward at the 

 surface 



3. Poleward aloft and 

 at the surface 



4. Equatorward aloft 

 and at the surface 



9-12. Excessive precipitation is characteristic 

 of the region of the doldrums because of 

 the region's 



1. low temperatures and divergent winds 



2. high temperatures and divergent winds 



3. low temperatures and convergent winds 



4. high temperatures and convergent winds 



9-13. Refer to figure 13-4 in your textbook. 

 The horse latitudes are bounded by the 



1. doldrums on the polar side, and the 

 trade winds on the equatorial side 



2. trade winds on the polar side, and the 

 doldrums on the equatorial side 



3. prevailing westerlies on the polar 

 side, and the trade winds on the 

 equatorial side 



4. polar easterlies on the polar side, 

 and the prevailing westerlies on the 

 equatorial side 



9-15. A wind that is blowing parallel to curved 

 isobars in a steady horizontal motion is 

 termed a/an 



1. gradient wind 



2. isallobaric wind 



3. geostrophic wind 



4. cyclostrophic wind 



9-16. Why do winds at high altitudes tend to 

 move faster than surface winds? 



1. The frictional force is weaker at 

 high altitudes 



2. The pressure force is stronger at 

 high altitudes 



3. The Coriolis effect is stronger at 

 high altitudes 



4. The Coriolis effect is weaker at 

 high altitudes 



9-17. Which of the following has the greatest 

 effect upon surface wind direction? 



1. Friction force 



2. Pressure gradient force 



3. Coriolis effect 



4. Centrifugal effect 



9-18. Cyclostrophic wind is the wind that 

 results when the 



1. Coriolis effect and centrifugal 

 effect are in balance 



2. pressure gradient force is balanced 

 by the Coriolis effect 



3. pressure gradient force is balanced 

 by the centrifugal effect 



4. centrifugal effect, pressure gradient 

 force, and Coriolis effect become 

 balanced 



9-19. Which of the following conditions is 

 generally associated with an area of 

 divergence? 



1. Precipitation 



2. High barometric pressure 



3. Upward flow of air currents 



4. Inward flow of air currents 



Learning Objective: Recognize the 

 effect of environmental factors on 

 climatic conditions throughout the 

 world. 



9-14. Which of the following factors affecting 

 wind direction and speed is due to the 

 curvature of the isobars? 



1. Pressure gradient force 



2. Centrifugal effect 



3. Frictional force 



4. Coriolis effect 



53 



