Oceanography
What do you know about
Oceanography?
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Water covers how much of the Earth?
The oceans contain how much of the water on
Earth?
How much of the ocean is unexplored?
What percentage of species are found in the
oceans?
How many jobs in the U.S. are water related?
What is the average depth of the ocean?
How deep is the deepest part of the ocean?
What is the maximum depth humans can go?
What is the maximum depth a vessel can reach?
Actual Percentages
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Water covers 71% of the Earth
The oceans contain 97.25% of all the water on
Earth
95% of the ocean is still unexplored
50% of all know species are found in the oceans
1 out of every 6 U.S. jobs is ocean related (16%)
The average depth of the ocean is 3720 meters
(2.3 miles, 12,303 feet)
The deepest part of the ocean is 11033 meters
(6.8 miles, 36,197 feet)
Humans can survive only 100 meters down (328
feet)
10,000 meters is the deepest any vessel can go
(32,808 feet)
Oceanography
 4500
m = DSV Alvin
 6000 m = submarines
 10,900 m = Bathyscaphe
Trieste (deep sea submarine)
Oceanography
 The
branch of science that studies the
ocean
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Marine life
Ocean currents
Waves and tsunamis
Geology of the sea floor
Weather affects
Tides
5 Main Oceans
 Atlantic
 Pacific
 Indian
 Arctic
 Southern
Salinity
 The
amount of dissolved salt in a body of
water
 Average salinity = 35 ppt OR 3.5%
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Fresh water salinity = 0.05%
Ocean Salinity
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Increase Salinity
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Evaporation
Ice formation
Volcanic activity
Depth
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Decrease Salinity
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Precipitation
Surface currents
River run off
Ice melt
Ocean Pressure
 Sea
level: a measure of the average
height of the oceans surface
 Pressure at sea level is 14.7 psi = 1 atm
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For every 10 m you travel down, the pressure
increases by 14.7 psi (1 atm)
Humans can travel down 3-4 atm and be OK
Ocean Pressure
 10
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14.7 x 2 = 29.4 psi
 20
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m down =
14.7 x 3 = 44.1 psi
 50
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m down =
m down =
14.7 x 6 = 88.2 psi
 100
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m down =
14.7 x 11 = 161.7 psi
Ocean Density
 Factors
that increase
ocean density
1. Temperature: Cold water is
more dense
2. Salinity: Water with more
dissolved salts is more
dense
3. Depth: Water sinks because
it is more dense
Ocean Temperature
 Ocean
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water has a wide range of temperatures
Average temp = 3.5 °C (38.3° F)
Ice Cap areas = 2 °C (35.6° F)
Coral Reef areas = 38°C (100.4°F)
Freezing point = -1.9°C (28.5° F)
Deep Sea Vents
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Also called hydrothermal vents
A break in the ocean floor where heated water escapes
Very high in nutrients but very low sunlight
Deep Sea Vent areas = 400 °C (752° F)
El Niño “little boy”
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Abnormal warming of ocean currents in the
Pacific Ocean
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Happens every 2-7 years
Causes: flooding on the American continents
and droughts on the Asian continent
La Niña “little girl”
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Abnormal cooling of ocean currents in the
Pacific Ocean
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Happens every 2-7 years
Causes: drier conditions on American continents
and wetter conditions on Asian continent