Lesson Outline:

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Lesson Outline
I. The Oceans
II. The Science of Oceanography
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The Oceans
It is the presence and abundance of water that
makes our planet unique in the solar system.
Without water, life would not exist on Earth.
Over 97 of the water on or near the Earths
surface is contained in the ocean, less than 3
is contained in land ice, groundwater, lakes and
rivers, and the atmosphere.
(However, there is much more water trapped in the
interior of the Earth than there is in the
oceans.)
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Importance of the Oceans
The oceans have always provided humans with an
abundant source of food.
Maritime routes allow for communication and the
trade of commercial goods between countries.
Reserves beneath the ocean floor now produce
about 30 of the worlds petroleum and natural
gas used for energy.
The oceans influence and moderate global climate.

The past, present, and future of the Earth and
its inhabitants is intimately bound to the ocean.
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Major Oceans
The world ocean may be defined as the entire body
of salt water that occupies the depressions in
the Earths surface.
Traditionally the world ocean is divided into
four major bodies
Atlantic Ocean Pacific Ocean Indian Ocean
Arctic Ocean
Southern Ocean
In some circles, the body of water surrounding
Antarctica is known as the Southern Ocean.
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The Size and Scale of the Oceans
On human scales, the ocean is vast.
The oceans cover about 139,400,000 square miles,
or about 71, of the Earths surface.
The average depth of the ocean is 12,450 feet
(compared to an average land elevation of 2,772
feet) and the total volume is 329,000,000 cubic
miles.
On a global scale, the ocean is almost
negligible.
Its average depth is only .05 of the radius of
the Earth.
The ocean accounts for only .13 of the Earths
volume and .02 of its total mass.
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The Science of Oceanography
Oceanography is an interdisciplinary field of
science rather than a field separate from the
other sciences.
Oceanographers typically start out in one of the
traditional areas of science (physics, chemistry,
biology, meteorology, or geology) or a
science-related field (engineering, computer
science, mathematics, or statistics), then apply
their knowledge to the study of the oceans.
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Fields of Oceanography
The science of oceanography can be subdivided
into four main fields

• Geological
• Chemical
• Physical
• Biological

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Geological Oceanography
Geological oceanography concerns the study of the
earth processes at the coastline as well as the
seafloor, and the history of the processes that
formed the ocean basins.
Marine geologists study the composition of the
inner earth, the movements of the Earths crust,
and the composition of seafloor sediments.
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Chemical Oceanography
Chemical oceanography studies the composition of
specific masses of seawater, their interactions
and change over time.
Chemical oceanographers study the solids and
gasses dissolved in seawater and the
relationships of these constituents to the
geology and biology of oceanic regions.
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Physical Oceanography
Physical oceanography investigates wave dynamics,
ocean currents, ocean-atmosphere interactions,
global heat-transfer and climate.
Physical oceanographers working with
meteorologists use observational studies and
complex computer models to predict long-term
weather patterns and impacts of global warming.
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Biological Oceanography
Biological oceanography concentrates on the study
of the plants and animals of the sea, and the
relationships of these organisms with the marine
environment.
Marine biologists work with the nature and
distribution of marine organisms, the impact of
pollution on marine populations, the isolation of
disease fighting drugs from marine species, and
the yields of fisheries.
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Fields of Oceanography
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Practice Exercise
The following is a list of some remarkable facts
about the worlds oceans. Classify each as to
whether they relate to biological (B), physical
(P), chemical (C), or geological (G)
oceanography. Many may fall under more than one
category.
1. Challenger Deep is the deepest point in the
ocean at 6.86 miles. (Note that Mount Everest,
the highest point on the Earth's surface, is only
5.49 miles high.) The average depth of the ocean
is more than 2 miles. .
2. The oceans provide 99 of the Earth's living
space. More than 90 of this habitat exists in
the deep sea known as the abyss, but less than
10 of this living space has been explored by
humans.
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3. The longest continuous mountain chain known on
earth resides in the ocean at more than 40,000
miles long.
4. The Monterey Bay Submarine Canyon is deeper
and larger in volume than the Grand Canyon.
5. The average temperature of the oceans is 2º C,
about 39º F.
6. The top ten feet of the ocean hold as much
heat as our entire atmosphere.
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7. Cold, saline water that forms off the coast of
Iceland can be found in the North Pacific Ocean
about 1000 years later.
8. The Gulf Stream off the Atlantic seaboard of
the United States transports nearly 300 times
more water by volume than the worlds largest
river, the Amazon.
9. The color blue is least absorbed by seawater
the same shade of blue is most absorbed by
microscopic plants, called phytoplankton,
drifting in seawater.
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10. The Great Barrier Reef, measuring 1,240
miles, is the largest living structure on Earth.
11. A new form of life, based on chemical energy
rather than light energy, resides in deep-sea
hydrothermal vents along mid-ocean ridges.
12. A swallow of seawater may contain millions of
bacterial cells, hundreds of thousands of
phytoplankton and tens of thousands of
zooplankton.
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13. More oil reaches the oceans each year as a
result of leaking automobiles and other non-point
sources that was spilled in Prince William Sound
by the Exxon Valdez.