The three major oceans are the Pacific, Atlantic, and Indian oceans. The Pacific is the largest and deepest ocean, while the Atlantic is shallow and salty. Methods used to study the oceans include satellites that gather data and sonar to map the ocean floor. Submersibles are underwater vessels used to explore the deepest ocean trenches. Salinity varies in the oceans depending on factors like evaporation, precipitation, and melting sea ice, with the average being 35 parts per thousand. Surface currents are generated by wind forces.
2. Major Oceans
• The three major oceans are :
Pacific
1._______-largest, deepest,
coldest, least salty. 2.__________- second
Atlantic
largest, shallow, warm, salty.
3. _________- intermediate in
Indian
depth, temperature, and salinity.
Arcti
• The _______Ocean near the north pole, and the
c
Antarctic
____________ Ocean near the south pole contain
vast expanses of sea ice.
3. Methods of Studying the Ocean
The Topex/Poseidon _____________ orbits 1331 km
satellite
above the Earth, gathering information about the
oceans.
Sonar
_____________ maps ocean floor topography
by timing how long it takes sound waves to
bounce off the ocean floor.
submersibles
Underwater vessels called _________________
investigate the deepest ocean trenches.
4. Sonar (also called echo-sounding)
• Sound waves travel
how fast in seawater?
1,454 m/s
• How deep is the
water if it takes ten
seconds for the sound
wave to go from ship
to ocean floor and
back to ship? 7,270 m
Calculation: (10 s times 1,454 m/s divided by 2 )
6. Salinity
The amount of salt per unit water is known as salinity.
NaC
The most abundant salt in seawater is ________, but there
are many other salts present in the form of ions.
l
The average salinity of seawater is _____ ppt. Therefore, for
35
every 1,000 ml water, there are ___ grams of dissolved salts.
35
Near the equator salinity is __________ than average due to
lower
greater precipitation
___________________.
lower
Near the poles salinity is __________ than average due to
melting sea ice
_______________.
higher
In the Mediterranean the salinity is __________than
average due to __________.
evaporation
8. Colorful Seawater
• What makes the ocean
water in the picture to the
left different colors?
differences in depth
• Why would a shrimp that
appears bright red at the
surface appear black at
greater depths, and why
might this be beneficial?
Longer (red) wavelengths are
absorbed before reaching
deep water. Shrimp can hide
and not become a meal.
9. Label the three ocean layers in the diagram below.
Surface layer
Thermocline
Bottom layer
10. Ocean Movements
Label the wave diagram below with the following
terms: wavelength, waveheight, trough, crest
crest
trough
wavelength
waveheight
11. Tides
Label the key
with the correct
tide cycle
names:
30
25
20
Sem idiurnal
semidiurnal
Mix ed
mixed
Diurnal
diurnal
15
10
5
0
0
4
8
12
16
20
24
12. Seafloor
Topographyterms to their
Match the following
H
A
correct letter in the diagram:
H.
Island
A.
Continental shelf
B.
Continental slope
D.
Abyssal plain
F.
Seamount
C.
Continental rise
G.
Trench
E.
Guyot
B
F
E
C
D
D
G
13. Listed below are some of the major surface currents. The force
wind
which generates these currents is ____________.
14. Chapter Review
1. What is the average salinity of seawater?
35 ppt
2. What is the deepest area of the seafloor?
trench
3. What is the largest ocean?
4. Why is the ocean “blue”?
Pacific
shorter wavelengths not absorbed
5. What is the force responsible for surface currents?
6. What causes density
wind
differences in temperature and
currents?salinity
7. What causes tides? gravity of the sun and moon
8. List the 3 tidal patterns.
diurnal, semidiurnal, mixed
9. What is the highest part of a wave called?
10. Name the ocean that borders Virginia.
crest
Atlantic
