This document is an Earth Science textbook chapter about oceans. It contains 5 sections that cover the following key points: Section 1 discusses the divisions of the global ocean, how the oceans formed over billions of years, and the characteristics of ocean water such as salinity, temperature, and role in the water cycle. Section 2 describes the two main regions of the ocean floor - the continental margin and deep ocean basin. It also discusses technologies used to study and map the ocean floor. Section 3 outlines the three main groups of marine life - plankton, nekton, and benthos. It also examines the benthic and pelagic environments and their ecological zones inhabited by different organisms.

1. WARMUP
*Have your Vocab Sheets laying out so I can
check them*
What percentage of earth do you think is covered
by water?

2. EXPLORING THE OCEANS
Earth Science: Book H, Chapter 2

3. SECTION 1: EARTH’S OCEANS
By the end of this section, you should be able to:
 List
the major divisions of the global ocean.
 Describe the history of Earth’s oceans.
 Identify the properties of ocean water.
 Describe the interactions between the ocean
and the atmosphere.

4. DIVISIONS OF THE GLOBAL OCEAN
 The
largest ocean is the Pacific Ocean.
 The
other oceans, listed from largest to
smallest, are:




the Atlantic Ocean
the Indian Ocean
the Arctic Ocean
the Southern Ocean

6. HOW DID THE OCEANS FORM?
 About
4.5 billion years ago, there were no
oceans.
 Sometime
before 4 billion years ago, water
vapor in the atmosphere condensed and fell as
rain.
rain filled the deeper levels of Earth’s
surface and the first oceans began to form.
 The
 The
shape of the oceans has changed over
time.

7. 
Need Pangaea image here

8. CHARACTERISTICS OF OCEAN WATER
 Nitrogen,
oxygen, and carbon dioxide are the
main gases dissolved in ocean water.
 Sodium
chloride, or table salt, is the most
abundant dissolved solid in the ocean. Other
solids are also found in ocean water.

9. CHARACTERISTICS OF OCEAN WATER
 Salinity
is a measure of the amount of dissolved
salts in a given amount of liquid.
 If
you evaporated 1 kg of ocean water, 965 g of
fresh water would be removed and 35 g of salts
would remain.

10. CHARACTERISTICS OF OCEAN WATER
 Climate
and water movement affect salinity.
 Coastal
water in cool, humid places has a low
salinity.
 Slow-moving
bodies of water, such as
bays, gulfs, and seas, have higher salinity than
other parts of the ocean do.

11. CHARACTERISTICS OF OCEAN WATER
 The
temperature of ocean water decreases as
depth increases.

12. CHARACTERISTICS OF OCEAN WATER
 Surface-zone
temperatures vary with latitude
and the time of year.
 Surface
temperatures range from 1ºC near the
poles to about 24 ºC near the equator.
 The
surface zone is heated more in the
summer.

14. THE OCEAN & THE WATER CYCLE
 The
water cycle is the continuous movement of
water from the ocean to the atmosphere to the
land and back to the ocean.
 The
ocean is an important part of the water
cycle because nearly all of Earth’s water is in
the ocean.

16. A GLOBAL THERMOSTAT
 The
ocean regulates atmospheric
temperatures.
 The
ocean absorbs and releases thermal
energy much more slowly than dry land does.
 The
circulation of warm water causes some
coastal lands to have warmer climates than
they would have without the currents.

18. SECTION REVIEW
p.45 #2-6, 8

19. WARMUP
If you walked off the edge of North America into
the depths of the Atlantic Ocean what would you
see?

20. SECTION 2: THE OCEAN FLOOR
By the end of this section, you should be able to:
 Describe
technologies for studying the ocean
floor.
 Identify the two major regions of the ocean
floor.
 Classify subdivisions and features of the two
major regions of the ocean floor.

21. STUDYING THE OCEAN FLOOR
 Scientists
depth.
use sonar to determine the ocean’s

22. STUDYING THE OCEAN FLOOR
 Scientists
use images from the satellite Seasat
to study ocean currents.
 Scientists
use the Geosat satellite to measure
slight changes in the height of the ocean’s
surface.

23. REVEALING THE OCEAN FLOOR
 The
two regions of the ocean floor are the
continental margin and the deep-ocean basin.
 The
continental margin is made of
continental crust and the deep-ocean basin
is made of oceanic crust.

24. REGIONS OF THE OCEAN FLOOR
 Continental
margin is subdivided into the
continental shelf, continental slope, and
continental rise.
 These
divisions are based on depth and
changes in slope.

26. REGIONS OF THE OCEAN FLOOR
 The
deep-ocean basin consists of the abyssal
plain, mid-ocean ridges, rift valleys, and ocean
trenches.
of these form near the boundaries of Earth’s
tectonic plates.
 All

27. REGIONS OF THE OCEAN FLOOR
 On
parts of the deep-ocean basin not near
plate boundaries, there are thousands of
seamounts.
 Seamounts
are submerged volcanic mountains
on the ocean floor.

29. EXPLORING THE OCEAN
 Alvin
and Deep Flight are two research vessels
that can reach some of the deepest parts of the
ocean.
 JASON
II and Medea are a robotic team.
JASON II explores the ocean floor. Medea is
attached to JASON II with a tether and explores
above the sea floor.

30. SECTION REVIEW
p.51 #2-7, 11

31. WARMUP
Imagine you are a marine biologist who must
classify marine life into 3 groups.
What criteria would you use for your classification
system?

32. SECTION 3: LIFE IN THE OCEAN
By the end of this section, you should be able to:
 Identify
the three groups of marine life.
 Describe the two main ocean environments.
 Identify the ecological zones of the benthic and
pelagic environments.

33. THREE GROUPS OF MARINE LIFE
 Organisms
that float or drift freely near the
ocean’s surface are called plankton.
 Organisms
that swim actively in the open ocean
are called nekton.
 Organisms
that live on or in the ocean floor are
called benthos.

35. THE BENTHIC ENVIRONMENT
 The
benthic environment is the region near the
bottom of a pond, lake, or ocean.
 The
benthic environment is divided into
ecological zones based on where different
types of benthos live.

36. THE BENTHIC ENVIRONMENT
 The
intertidal zone is where the ocean meets the
land.
 The
intertidal zone is exposed to air for part of
the day. Organisms found in this zone include
starfish, sea anemones, barnacles, crabs, and
seaweed.

37. THE BENTHIC ENVIRONMENT
 The
sublittoral zone begins at the low-tide limit
and extends to the continental shelf, which is
about 200 m below sea level.
 The
temperature, water pressure, and amount
of sunlight remain fairly constant in this zone.
Coral is found in this zone.

38. THE BENTHIC ENVIRONMENT
 The
bathyal zone extends from the continental
shelf to the abyssal zone. The depth of this zone
ranges from 200 m to 4,000 m below sea level.
 Because
of the lack of sunlight, few plants are
found in this zone. Animals such as sea
stars, sponges, and octopuses are found here.

39. THE BENTHIC ENVIRONMENT

The abyssal zone is the largest ecological zone of
the ocean and can reach 4,000 m in depth.

No plants live in this zone. The few animals that
can be found include crabs, sponges, sea
cucumbers, and worms.

40. THE BENTHIC ENVIRONMENT
 The
hadal zone consists of the floor of the ocean
trenches and any organisms found there. The
depth can reach from 6,000 m to 7,000 m below
sea level.
 The
only organisms that have been found in this
zone include a type of sponge, a few species of
worms, and a type of clam.

41. THE PELAGIC ENVIRONMENT
zone near the ocean’s surface and at the
middle depths is called the pelagic
environment.
 The
 The
pelagic environment is above the abyssal
zone and beyond the littoral zone.
 The
two major zones of the pelagic
environment are the neritic zone and the
oceanic zone.

42. THE PELAGIC ENVIRONMENT
 The
neritic zone is a warm, shallow zone that
covers the continental shelf.
 The
neritic zone contains the largest
concentration of marine life.

43. THE PELAGIC ENVIRONMENT
 The
neritic zone receives more sunlight than
other ocean zones, allowing plankton to grow
and serve as a food supply.

44. THE PELAGIC ENVIRONMENT
 The
oceanic zone includes the volume of water
that covers the entire sea floor except for the
continental shelf.
 The
deeper parts of the oceanic zone have
colder water temperatures and much greater
pressure than the neritic zone.

45. THE PELAGIC ENVIRONMENT
 Organisms
zone.
are more spread out in the oceanic

46. SECTION REVIEW
p.57 #1-5,7,9

47. WARMUP
Samantha drove her car to the market to buy a
tuna steak for dinner. When she got home she
poured herself a glass of water, and then fired up
her gas grill to cook the tuna.
What are 3 items or activities mentioned above
that involve ocean resources?

48. SECTION 4:
RESOURCES FROM THE OCEAN
By the end of this section, you should be able to:
two ways of harvesting the ocean’s living
resources.
 Identify three nonliving resources in the ocean.
 Describe the ocean’s energy resources.
 List

49. LIVING RESOURCES
 Fish
are the largest group of organisms taken
from the ocean.
 People
have begun to raise ocean fish and
other organisms in fish farms to help meet the
demand for seafood.

50. LIVING RESOURCES
 Many
types of seaweed are harvested from the
ocean for use as food.

51. NONLIVING RESOURCES
 Oil
and natural gas are used for energy and are
found under layers of impermeable rock.
 Scientists
use seismic equipment to find oil and
natural gas under the ocean floor.

52. NONLIVING RESOURCES
 Fresh
water can be collected for human use by
desalination, the process of removing the salt
from ocean water.

53. NONLIVING RESOURCES
 Scientists
estimate that 15% of the ocean floor
is covered with mineral-rich nodules.
However, mining them is costly and difficult.
 Nodules
form from dissolved substances in sea
water that stick to solid objects, such as
pebbles.

55. NONLIVING RESOURCES
 The
constant motion of waves is a
clean, renewable energy resource.
 Researchers
have found certain areas of the
world where wave energy can generate enough
electrical energy to make building power plants
worthwhile.

56. SECTION REVIEW
p.63 #2-7

57. WARMUP
How do you contribute to ocean pollution in your
daily lives?

58. SECTION 5: OCEAN POLLUTION
By the end of this section, you should be able to:
 Explain
the difference between point-source
and nonpoint-source pollution
 Identify three different types of point-source
pollution.
 Describe what is being done to control ocean
pollution.

59. NONPOINT-SOURCE POLLUTION
 Pollution
that comes from many sources rather
than from a single site is called nonpoint-source
pollution.
 Most
ocean pollution is nonpoint-source
pollution and can be difficult to regulate and
control.

60. POINT-SOURCE POLLUTION
 Dumping
trash in the deeper parts of the ocean
is a common practice in many countries.
 Trash
thrown in the ocean can be harmful to
ocean organisms.

61. POINT-SOURCE POLLUTION
 Sludge
is the solid waste removed from raw
sewage. Sludge can pollute beaches and kill
marine life.

62. POINT-SOURCE POLLUTION
 If
not handled properly, oil transports can cause
oil spills.

63. POINT-SOURCE POLLUTION
 Oil
spills can harm or kill many plants and
animals.

64. POINT-SOURCE POLLUTION
 New
technology is being used to safeguard
against oil spills. Oil tankers are now being built
with two hulls instead of one.

65. SAVING OUR OCEAN RESOURCES
 Many
international agreements and laws
restrict ocean pollution.
 People
have demanded that their governments
work to solve ocean pollution and have begun
organizing beach cleanups.

66. SAVING OUR OCEAN RESOURCES
 The
U.S. has passed laws to control local
pollution.
 Some
of these laws include the Clean Water
Act and the U.S. Marine
Protection, Research, and Sanctuaries Act.

67. SECTION REVIEW
p.69 #2-6