Practice Quiz – Chapter 12

1. Which region is not considered to be a region where cyclogenesis often occurs:

a. eastern slopes of the Rocky Mountains

b. Atlantic Ocean near Cape Hatteras, North Carolina

c. California

d. the Great Basin of the United States

e. Gulf of Mexico

2. 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

3. 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

4. If the flow of air into a surface low pressure area is greater than the divergence of air aloft, the surface pressure in the center of the low will:

a. increase

b. decrease

c. remain the same

d. deepen

5. A surface low pressure area with a deep upper-level trough to the west will tend to move toward the:

a. northwest

b. northeast

c. southwest

d. southeast

6. When an upper-level low lies directly above a surface low:

a. the surface low will probably weaken

b. thunderstorms will develop

c. a wave cyclone will begin to form

d. the pressure of the surface low will decrease

e. cyclogenesis will occur

7. 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

8. 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

9. If the outflow of air around a surface high pressure area is greater than the convergence of air aloft, you would observe:

a. an increase in pressure in the center of the high

b. movement of the high toward the northeast

c. a decrease in the central pressure

d. strengthening in the high

10. Longwaves in the middle and upper troposphere usually have lengths on the order of:

a. tens of kilometers

b. hundreds of kilometers

c. thousands of kilometers

d. millions of kilometers

11. An upper-level trough that shows retrograde motion would probably be moving toward the:

a. west

b. east

c. north

d. south

12. Atmospheric shortwaves usually move _____ at a speed that is _____ than longwaves.

a. east to west, faster

b. west to east, faster

c. east to west, slower

d. west to east, slower

13. Suppose it is warm and raining, and a cold front is moving toward your location. Directly behind the cold front it is cold and snowing. Still further behind the front the weather is cold and clearing. If the front is scheduled to pass your area in 6 hours, a persistence forecast for your area for 12 hours from now would be:

a. cold and snowing

b. cold and clearing

c. cold and cloudy

d. warm and raining

e. not enough information on which to base a forecast

14. On an upper-level chart where the isotherms cross the isobars (or contours) and temperature advection occurs, the atmosphere is called:

a. barotropic

b. geostrophic

c. hydrostatic

d. baroclinic

15. Which of the following statements is not correct about vorticity?

a. the earth's vorticity in the Northern Hemisphere is positive

b. the earth's vorticity is zero at the poles

c. air that spins cyclonically possesses positive vorticity

d. absolute vorticity is the sum of the earth's vorticity and the relative vorticity