Page 228 - NS-2 Textbook

OCEANOGRAPHY 223

18. A. What is a I011gshore current? B. Which persons aboard ship are particularly con-
B. What type of structure is built to prevent erosion cerned about the tides? Why?
from these currents? 28. Where do the world's highest tides occur?
19. A. What is a rip current, and how may it affect swim- 29. A. What is a tidal bore?
mers? B. Where do the highest tidal bores occur?
B. How should a swimmer move to get out of a rip 30. What is the general theory of operation of a tidal
current? power plant?
20. A. What force, caused by Earth's rotation, affects
the major currents of the world ocean? Vocabulary
B. In what direction does this force deflect major
thermostat surf
currents north and south of the equator?
absorption breakers
21. What very important current affecting the United
suspension rip current
States originates on the southern border of the Sar-
broach (boat) gyre
gasso Sea?
22. A. Which current brings icebergs into the North refraction (water wave) Gulf Stream
Atlantic shipping lanes? breakwater calved (iceberg)
B. How does the Gulf Stream affect icebergs? longshore current Sargasso Sea
23. A. What important current in the North Pacific has groin countercurrent
many similarities with the Gulf Stream in the soluble Svvallo,v buoy
North Atlantic? hydrologic cycle tide
B. What severe storms originate in the same general transpiration spring tide
area as does this current? bathythermograph neap tide
24. A. How do deeper water layers often move in rela- Nansen bottle ebb and flood tides
tion to the major surface currents? spectrum tidal bore
B. What are these subsurface currents called? prism swell
25. A. What is the main cause of the ocean tides? ultraviolet period (water wave)
B. How does the Sun affect the tides? infrared fjord
26. When are tides highest and lowest, and what are graving basin estuary
these tides called? crest (water wave) turbine
27. A. How do naval personnel find out about the tidal trough (water wave) sluice
situation in their port of call? fetch (water wave)