Module 3_3 Quiz

1. Which of the following atmospheric processes can create ducts? Choose one best answer.

a) Subsidence

b) Mixing

c) Surface fluxes

d)All of the above

e) None of the above

2. Why does subsidence sometimes cause a duct to form?

a) The downward vertical velocity of the higher air parcels is greater than the lower parcels.

b) The subsidence causses the (positive potential temperture gradient near the surface to weaken.

c) The subsidence causes the (negative) vapor pressure gradient near the surface to weaken.

d) b and c above are both correct.

e)None of the above

3. Where does subsidence typically occur?

a) In regions of low surface pressure.

b)Behind (to the west in mid-latitudes) upper level ridges

c) In the center of cyclones.

d) In all of the above locations.

e) In none of the above locations.

4. In what region on Earth is subsidence most common?

a) Subtropical High Pressure Belt ("Horse Latitudes").

b) Inter-Tropical Convergence Zone ("Doldrums").

c) Mid-latitude regions with west-to-east moving storm systems.

d) All of the above.

e) None of the above.

5. What happens to the conserved quantities vapor pressure, e, and potential temperature θ, in mixed layers?

a) The vertical gradients of e and θ are strong.

b) The values of e and θ are constant with elevation.

c) The value of e increases with elevation and the value of θ decreases with elevation.

d) The value of e decreases with elevation and the value of θ increases with elevation.

None of the above.

6. Why can mixing and the formation of mixed layers sometimes cause ducts?

a) Mixing can cause jumps in e and θ at the top of the mixed layer.

b) Mixing can cause jumps in e and θ at the bottom of the mixed layer.

c) Mixing can cause jumps in e and θ within the mixed layer.

d) All of the above are correct.

e) None of the above are correct.

7. Which of the following differential horizontal advection scenarios is most likely to form a duct?

a) Cold air is advected (horizontally transported into the region) above a region of warm air advection.

b) Moist air is advected above a region of dry air advection.

c) Warm dry air is advected below a region of cool moist air advection.

d) All of the above could form a duct.

e) None of the above are likely to form a duct.

Show me the answers!

Question 1: The correct answer is c) All of those processes: subsidence, mixing and surface fluxes, can create ducts. .

Question 2: Subsidence sometimes causes a duct to form because a) The downward vertical velocity of the higher air parcels is greater than the lower parcels.

Question 3: The correct answer is e) None of the above..

Question 4: The correct answer for where subsidence is most common is a)Subtropical High Pressure Belt, i.e. the "horse latitudes".

Question 5: The correct answer is b)vapor pressure and potential temperature are constant in elevation in mixed layers.

Question 6: The correct answer is a)Mixing can cause jumps in e and θ at the top of the mixed layer.

Question 7: The correct answer is e)None of those scenarios is likely to form a duct.

You answered them all right!