Download oceanography study guide 2015

Name_________________ Tentative Test date: Friday May 20
Oceanography Study Guide
The Blue Planet: About 71% of the Earth’s surface is covered by water.
 A cold polar ocean and the smallest of the 5 oceans
Arctic Ocean
Atlantic
Ocean
 Runs from the North Pole to the South Pole
 Continental shelf is longer and more sloping on the Atlantic (Eastern) coast of the US
than the west coast (the Pacific)
 It is generally the warmest ocean because it is primarily located in the tropics.
 The largest & deepest ocean
 Has a shorter continental shelf on the Pacific (Western) coast of the U.S. than the
Atlantic on the east coast .
 Also known as the Antarctic Ocean
Indian Ocean
Pacific Ocean
Southern
Ocean
The Salty Sea
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Salinity
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Density
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Brackish
water
Estuary
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Desalination
baseword:salt
de: not
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How much salt is in a substance, especially ocean water
Higher salinity  lower freezing point, so saltier water freezes slower
In warm, dry places, evaporation and low precipitation cause the ocean to have a
high salinity
In cold places, salinity is lower because of less evaporation, and melting snow and ice
adding fresh water to the ocean
The concentration of matter in an object.
Saltier, colder water is denser than less salty, warmer water.
A mix of fresh and salt water
Found in bays, estuaries and the mouth of rivers
The place where a fresh water river empties into an ocean.
All estuaries have changing water conditions. At high tide, salty ocean water flows in.
At low tide, estuaries are filled with fresh water or become exposed muddy areas.
Organisms found here have adapted so they can survive in salt AND fresh water, or
brackish water
Chesapeake Bay is the largest estuary in the U.S.
Humans can not drink salt water. Most of the world’s water is salt water. Where
fresh water is not available, the salt can be removed and the water made drinkable
by desalination.
Water Movement
Water in the ocean moves in different ways. Currents, tides and waves have different causes.
Currents
Current
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Causes
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A stream of water that flows like a river through the ocean
2 Types of currents: Horizontal & Vertical
Temperature -cold water sinks to the bottom because it is more dense
Salinity – more salinity →denser water. The less salty water rises
Winds - winds that blow in the same direction year around
 Gulf Stream – a warm surface current that flows from the Caribbean Sea
north along the East Coast and east across the Atlantic Ocean to Europe.
Tides
Tides
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The repeated rise and fall in the level of the ocean
Caused by the gravity of the moon and sun on the
Earth’s waters
 Although it is smaller than the sun, the moon has
a much greater effect on the tides because it is so
much closer to the Earth.
 There are generally 2 high and 2 low tides in a 24
hour period.
Waves
Wave
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Tsunami
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Peak (Crest)
Trough
Wavelength
Wave Height
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An up-and-down movement of surface water.
Is actually energy traveling through the water.
Most waves are caused by wind.
Can erode beaches
A giant wave caused by the energy released in
an underwater earthquake or volcano
The top of a wave
The bottom of a wave
The distance from the crest of one wave to the crest of the next
How high a wave is
The Parts of the Ocean Floor
Sea Level
Continental
Shelf
Continental
Slope
Continental
Rise
Abyssal or
Seafloor
Plains
Ocean Basin
Mid-Ocean
Ridge
Trenches
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The level where the ocean meets land
 The underwater “edges” of the continents, no deeper than 140 m or 460 ft below
sea level
 Most fishing, boating and swimming is done on the continental shelf.
 The steep drop-off from the continental shelf to about 3000 m (10,000 ft) below sea
level.
 The piled up sediments that have fallen off the continental shelf which form a more
gentle slope.
Sediment
 Small pieces of rock, sand and soil that have been broken off of larger
(from your
pieces of rock by weathering
GEOLOGY
 Sediment can settle in layers to become sedimentary rock
unit!!)
 Sediment can also be moved from one place to another by wind and
water
 The broad, flat part of the ocean floor.
 These plains are flatter than the plains on land.
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Sea Mount
Island
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Large round pits on the sea floor (not as deep as a trench).
Continuous undersea mountain ranges that run through the middle of the ocean
basins, where tectonic plates are pulling apart.
Narrow valleys that form the deepest part of the ocean floor
The deepest trench is the Mariana Trench, near the Philippines in the Pacific Ocean.
It is 11 km below sea level. Mt. Everest is only about 9 km above sea level!
An underwater mountain formed by a volcano
A seamount that rises above sea level and is completely surrounded by water.
Life in the Ocean
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Sunlight /
Surface Zone
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Twilight /
Thermocline
Zone
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Deep Sea or
Midnight Zone
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Phytoplankton
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Zooplankton
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The top layer of the ocean
The only zone with enough light to support plant life (including phytoplankton)
The tide & churning waves provide oxygen & nutrients
Below the sunlight zone
Plants can’t grow because it doesn't receive sunlight (no photosynthesis)
Water calm (not affected by wind) and temperature steady
Some animals in this zone swim to the sunlight zone to eat, some eat remains that
drift down from sunlight zone above due to gravity
No light can penetrate
Water pressure very high (> 2 tons per square inch)
Temperature very low (close to freezing)
Very little life in this zone
Microscopic organisms that perform photosynthesis and live in the sunlight zone
The base of most ocean food chains (except those supported by hydrothermal
vents)
Accounts for 50% of all oxygen on Earth!
Microscopic organisms that feed on phytoplankton or each other
Live in the sunlight zone
Prey for many marine animals
Ecosystems – Organisms and Their Environment (review from 4th)
Individual
Population
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Community
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Ecosystem
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Habitat
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Niche
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A single organism in an environment, e.g. a single dolphin in the ocean.
Individuals of the same kind of living thing in the same environment, e.g. all the dolphins in
the ocean.
All the populations of organisms living together in the same environment, e.g., all the
dolphins, sharks, phytoplankton, etc. living together.
A community AND its environment, e.g., all the animals in the ocean and the ocean water,
floor, etc. working together.
A place in an ecosystem where a community lives. You can think of it as a neighborhood,
e.g., the starfish live in the intertidal/sunlight zone.
The role each population has in its habitat. Are the niches of a dolphin and a phytoplankton
the same?
Consumer
Producer
Decomposer
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An organism in a community that must eat to get the energy it needs.
An organism that makes its own food.
A consumer organism that breaks down the tissues of dead organisms.
Energy Pyramid
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Shows the amount of energy available to pass from one level of a food chain to the next.
Human Exploration
SONAR
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Submersible
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SOund NAvigation and Ranging
With SONAR, scientists send sound waves into the ocean until they reflect (or echo) back.
These measurements are graphed, allowing us to map the ocean floor.
Small, underwater vehicles also used to explore the ocean that can withstand a greater
amount of water pressure than a human can.
An example of a submersible is the Alvin. It was the first submersible to explore the
wreckage of the Titanic.
SONAR