Homework Questions #5:
Due: Friday, May 3
1. Tropical cyclones are called _________________________________ in the Atlantic Ocean,
____________________________ in the West Pacific Ocean and ______________________
in the Indian Ocean.
2. Winds circulate in a ______________________________ direction around a tropical cyclone.
3. Tropical cyclones have ________________ pressure at the surface and __________________
pressure aloft.
4. The energy source for tropical cyclones is__________________________________________
which is released as vast amounts of __________________________ generated by the heavy
precipitation in the core of these storms.
5. The shape of tropical cyclones is more _________________ and _______________________
than extratropical cyclones because they form where there is little temperature contrast and,
therefore, they do not develop “fronts”.
6. Why are tropical cyclones “the most destructive storms on earth”?
7. Vertical wind shear will _________________________________ a tropical cyclone.
8. Why does vertical wind shear have this effect upon a tropical cyclone?
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9. The air ______________________ in the eye of a tropical cyclone, which results in clear
skies.
10. The most intense updrafts and strongest winds are found in the ________________________
of a tropical cyclone.
11. List the four environmental requirements for tropical cyclone formation.
12. Because of one of the necessity for warm sea surface temperatures, tropical cyclones usually
only form in the ___________________________ and ______________________ seasons.
13. Why does the warm surface water layer need to be at least 60 meters deep in order for a
tropical cyclone to form?
14. Why do tropical cyclones not form within 5 degrees of the equator?
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15. Tropical cyclones originate as ___________________________________________ within
or near the ITCZ.
16. Tropical cyclones in the Atlantic Ocean most frequently originate from _________________
______________________________________ which form over the African continent
during the monsoon season.
17. Even though these African weather systems can become destructive tropical cyclones, they
severe an extremely important function for the African people. What is that function?
18. Tropical cyclones tend to continue to deepen and strengthen because of a ________________
feedback process.
19. What is a tropical disturbance?
20. When a tropical disturbance develops a low pressure center and cyclonic circulation it is
called a ___________________________________________.
21. A tropical cyclone receives a name when it becomes a ______________________________.
22. When sustained winds reach 74 mph a tropical cyclone in the Atlantic Ocean becomes a
________________________________.
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23. Tropical cyclones tend to track with the anticyclonic flow around the
_________________________________________________________________.
24. True or false..........The majority of tropical cyclones make landfall.
25. If a tropical cyclone reaches middle latitudes it may undergo an extropical transition in
which it begins to feed off the energy of _______________________________, develop
___________________ and become a(n) _________________________________________.
26. What two conditions will generally result in intensification of a tropical cyclone?
27. What three mechanisms result in the weakening and eventual demise of a tropical cyclone?
28. What two things about tropical cyclone landfall results in its eventual demise?
29. “Hurricane season” in the Atlantic Ocean runs from _________________________ to
___________________________with a peak in _____________________________.
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30. a) Hurricanes are categorized by intensity based upon ______________________________.
b) The intensity scale is called the ______________________________________________.
31. What are the three tropical cyclone “modes of destruction”?
32. a) Which of these three modes causes the most hurricane/typhoon/cyclone (of hurricane
strength) related fatalities?
b) Which of these three modes causes the most deaths related to all tropical cyclone (not
necessarily of hurricane strength) activity?
33. The storm surge is greatest to the ________________________ of the path of the eye of a
tropical cyclone.
34. The storm surge may be enhanced by ________________________________________ and
_____________________________________________________.
35. Hurricane Katrina (HK) occurred during the 2005 season which was ___________________
__________________________________________hurricane season of modern times.
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36. HK rapidly intensified as it moved over the warm waters of __________________________
in the Gulf of Mexico.
37. Although HK was a powerful Category 5 hurricane in the Gulf of Mexico, it made landfall
as a Category ______ hurricane.
38. The National Hurricane Center’s “best track” forecast made 56 hours before landfall
eventually verified as ____________________________________________.
39. True or False........................ “No one could have anticipated the failure of New Orleans’
levee system” during HK.
40. a) The levee system was built to withstand a Category _______ hurricane.
b) The levees are now being rebuilt to withstand a Category _______ hurricane.
41. True or False.........Mayor Nagin ordered a mandatory evacuation as soon as it became
apparent that HK, then a powerful Category 5 hurricane, was destined to make landfall near
New Orleans.
42. The majority of the levees failed because: a) they were overtopped by the storm surge or
b) they collapsed due to poor construction and maintainance.
43. True or False...The Coast Guard and National Guard rescued 58,000 people in New Orleans.
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44. During which tropical cyclone were there more fatalities, Hurricane Katrina or the 1970
Bangladesh (Bhola) Cyclone?
45. a) Tropical cyclone frequency has _____________________________ since 1970.
b) Tropical cyclone intensity has ____________________________ since 1970 and “likely”
will continue to __________________________ with further global warming.
46. What environmental condition, which has been increasing, is likely most responsible for this
change in tropical cyclone intensity?
47. What other global warming consequence is likely to result in an increase in the impact of
any given tropical cyclone?
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