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Unit 1, Part 2 Study Guide
Ocean Basins – low spots on earth completely or partially surrounded by land
Oceans – basins where water has collected and remained over millions of years
What are the earth’s 5 main ocean basins and oceans?
1. Pacific ocean (largest)
2. Atlantic ocean (2nd largest)
3. Indian ocean (3rd largest)
4. Southern ocean (Antarctica) (4th largest)
5. Arctic ocean (smallest)
Continental Drainage System – created by glaciers as they eroded the land.
Water from rain and snow drains downhill and collects in continental drainage
systems/basins such as lakes, rivers and oceans!
Canada’s 5 Major Drainage Basins
FYI: Refer to page 27 of your book for Newfoundland and Labrador’s drainage
basins.
1.
1. Volcanic Action
- Page 40 – 41 of textbook. Basically, 4.5 billion year ago, the planet was a hot
ball of molten (melted rock). As the outside of the earth cooled, heat was still
released from deep inside through volcanoes. Water trapped inside the volcanoes
material was released into the atmosphere as water vapor. When the vapor cooled
and condensed it fell to the earth as precipitation which flowed downhill and
collected in ocean basins.
2. Plate Tectonics
- Page 40 – 44 of your text book.
- Plate tectonics is the theory that the earth was once a giant supercontinent called
Pangea. Over time, the supercontinent broke apart and large pieces of land sitting
on plates (large pieces of slow moving rock) began to move away from each other.
- As plates move apart or come back together, they form trenches and mountains.
This plate movement has the greatest influence in shaping the ocean floor.
3. Erosion
- Erosion is the removal of sediment, sand, soil, rock and other materials by
glaciers, wind and/or water.
- Many years ago, glaciers moved very slowly and eroded away the land creating
many of the continental drainage systems we have today.
4. Glaciation
- Many years ago, glaciers moved very slowly and eroded away the land creating
many of the continental drainage systems we have today
- The were and still are a major force of erosion
Using a Diagram, illustrate a typical oceanic basin from coastal shoreline to
mid ocean ridge including continental shelf, continental slope, abyssal plain
and mid-ocean ridge!
Continental Margin – ocean basins begin many kilometers out to sea. The area
between the basin and the shoreline is the continental margin, made up of the
continental shelf and the continental slope.
 Sediments, which are created from rocks eroded by weather, are carried by
rivers into oceans and eventually end up into oceans, settling on the
continental shelves or on abyssal plains!
Continental Shelf – found under water between the coastline and the edge of the
basin. They slope gradually away from the land before dropping steeply.
 The continental shelf off of Newfoundland, toward the Grand Banks, is 480
km, one of the widest in the world since most are only 80 km wide!
 Water can be anywhere from 30 m to 600 m deep on the shelf!
Continental Slope – the steeply sloping area on the end of the continental shelf.
 They are usually less than 200 km wide and drop approximately 3 km
downward
Abyssal Plain – the floor of the ocean basin which is somewhat flat
 It is made up thick sediment up to 1 km thick that usually reaches the plain
by underwater landslides usually started by earthquakes or the pile up of
sediment.
Mid-Ocean Ridges – chains of volcanic mountains rising up from the middle of
the ocean floor
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Youngest part of the ocean floor and still being formed today
Can be 1000 km wide
Can rise 1000 – 3000 km above the sea floor
Largest is the Mid-Atlantic ridge in the Atlantic Ocean
Sonar – Sonar uses sound waves to map out the ocean floor.
 The depth of water is found by sending sound waves directly down from the
boat and measuring the time it takes for the signal to hit the sea floor and
bounce back to the surface
 Fish finders use Sonar technology to find fish
Satellites – Satellites orbit far above earth and can send and receive information
from earth
 Satellites can use radar and other technologies to measure different features
on earth such as mountains, trenches and even the ocean floor!
 An advantage to using satellites is that they can measure large areas of ocean
in a very short time
 Satellites can also send and receive data in all kinds of weather, both day and
night!
 Satellites can also receive information from buoys that are anchored to the
sea floor and can help collect information about water and air temperature.
They satellites can transmit this information all over the world!
Many satellites orbit the earth. This photo just shows some of the newest satellites
designed by NASA.
Underwater photography and videography – underwater cameras and video
cameras
 Cameras towed by ships can take thousands of high resolution photographs a
day to share with the world
 New deep sea cameras and video cameras can be used up to 6000 m below
the ocean surface
 These cameras have allowed scientist to explore the ocean floor and find
new species!
 The NEPTUNE deep sea camera has 2 photo cameras, a video camera, lights
and a battery pack that can go 6000 m down into the ocean! (picture above)
Deep Sea Submersibles – small but extremely strong vehicles that are capable of
going deep into the ocean
 The most detailed information we have about the deep ocean come from
submersibles
 There are 2 types of submersibles:
o 1) Manned – carries people in it; can be dangerous and cannot stay
underwater for as long
o 2) Remotely Operated Vehicle (ROV) – someone controls the vehicle
from the ship; less dangerous and can stay underwater for longer
 Scientists are working on a 3rd submersible called an automated underwater
vehicle which can use artificial intelligence, needs little control from people
and can stay underwater for months at a time.
This is a manned submersible. People sit inside, drive the vehicle and make
observations through the large glass window.
An ROV is much smaller and often has mechanical hands/arms for performing
tasks. It is run using cameras and is connected to the ship by a tether rope.
Humans control it much like playing a video game!
Diving – SCUBA diving refers to wearing diving suits and using oxygen tanks to
swim underwater. SCUBA is an acronym for Self Contained Underwater Breathing
Apparatus!
 Commercial divers are those who are hired to perform underwater jobs
 Technical diving allows divers to dive deeper than 40 m (130 ft)
 Divers can be used to explore shallow waters, used by police and army for
searches and can even take underwater photo and video.
 Divers cannot be used to explore the deep ocean
How have technologies used to study the ocean floor improved over time?
 Divers can now dive deeper than ever before and for longer
 Submersibles have replaced divers and can now explore deeper and stay
underwater longer
 Sonar has replaced wire line depth probes and is more efficient and accurate
 Satellites are not affected by darkness or weather, can send information
instantly all over the world and gathers large amounts of information very
quickly
Identify strengths and weaknesses of technologies used to study the ocean
Strengths
Sonar
- Accurate
- Scientists have been able to
map out mountains, valleys and
canyons on the ocean floor
Satellites
-Cover large areas quickly
-Sends information worldwide
quickly
-Not affected by weather or
darkness
-Takes thousands of high
resolution photos in a day
-Creates photos and videos to
be observed later
-ROVs are safe and can stay
underwater for long period s of
time
-Allows us to explore deepest
parts of the ocean
-Hand on observation
-Good for shallow waters
because it is cheap and easy
Underwater
cameras
Submersibles
Diving
Weakness
-Sonar can harm marine
animals (confuse animals
that use sound for mating
and feeding)
-Can be affected by
weather and waves
-In space and difficult to
locate to fix
-Usually remains in space
as space junk
- Affected by muddy
waters and waves
- Cannot go very deep
-Manned can be
dangerous and cannot stay
underwater for long
- Expensive and technical
-Cannot be used to
explore deep ocean
-Safety issues when using
humans
It is important to realize that no single method can collect enough data to give
us a complete picture of the ocean floor. We need to use evidence from a
variety of sources to get an accurate view!
* Provide examples of public and private Canadian institutions that support
scientific and technological research involving oceans.
1. Environment Canada – a Canadian Government department that is responsible
for environmental programs that help protect the environment and make sure it is
being used properly. It also keeps a close eye on our weather.
2. Federal Fisheries – Fisheries and Oceans Canada is another Canadian
Government department that makes the rules around fishing and hunting in the
oceans.
3. Ocean Sciences Centre – an ocean research office located in Memorial
University
4. C-CORE (Centre for Cold Ocean Research) – another Memorial University
research centre
Ocean Current – a continuous, directed movement of water
- Newfoundland is affected by 2 ocean currents:
1. The Labrador Current – a cold water current which flows from the Arctic Ocean
down past Newfoundland
2. The Gulf Stream – a warm water current which flows from the top of Florida up
past Newfoundland and then across the Atlantic Ocean
When these currents meet, the warm and cold water combination often leads to fog
which is why St. John’s experiences a lot of fog!
- The 2 types of ocean currents are:
1. Surface currents – currents that exist within the top 200 m of ocean
2. Deep water currents – currents that exist beyond 200 m of the ocean
What causes surface currents?
1. Wind – the wind is a mass of air moving from one are to another because of
uneven heating of the earth’s surface. The direction and speed of wind blowing
over the water affects surface currents
2. Earth’s spin – the earth spins counterclockwise from West to East. As currents
flow over the spinning earth their paths change. This change in direction is called
the Coriolis Effect. Because the earth is always spinning, air currents flow
clockwise in the northern hemisphere and counterclockwise in the southern
hemisphere.
3. Shape of Continents – When currents hit a solid surface (land) they are forced to
change direction. Continents either deflect currents North or South.
What influences the formation and movement of deep water currents?
1. Temperature – temperature differences in water can cause vertical convection
currents. Warm water will continually be pushed to the surface by cold water that
will sink.
2. Salinity – Water with high salinity is denser and will sink more quickly. Areas
with high evaporation rates are saltier and denser. This water will sink and form a
downward moving density current. When water freezes, salt is left behind. At the
north and south poles, water is denser. Water near the equator is also saltier and
denser.
Upwelling areas – an area where deep cold water is pushed to the surface and
carries nutrient rich ocean water with it which often attracts organisms.
The collision of the Labrador Current and the Gulf Stream has created a nutrient
rich upwelling area off Newfoundland called “The Grand Banks” which has been
known as one of the world’s most productive fishing grounds!
Wave – moving water that transfers energy
Waves are generated when the energy of wind is transferred across the surface of a
body of water. The sizes of waves are influenced by the speed and duration of
wind as well as the size of the water body it is passing over!
Features of a Wave
Crest – the top of the wave
Trough – the bottom of the wave
Wave length – the distance between the crests of 2 waves
Wave Height – the height of a wave from the bottom of the trough to the top of the
crest
* As waves approach the shoreline, the wave length decreases but the wave height
increases.
Ocean waves – Ocean waves begin out on the open ocean, thousands of kilometers
away from shore. As they come close to shore, their wave length decreases but
their wave height increases
Swells – A long, smooth wave that moves steadily without breaking on shore.
They are caused by winds and storms far out on the ocean.
Breakers – when waves hit the shoreline they are called breakers.
Tsunami – large waves that are set in motion by earthquakes on the ocean floor,
landslides or volcanic eruptions near shorelines.
In 1929, Newfoundland experienced a Tsunami. It affected the Burin Peninsula on
Newfoundland’s south coast. It was caused by an earthquake that happened in the
middle of the Atlantic Ocean.
When waves come in contact with the shoreline, the energy is used to erode and
reshape the coast. Most shoreline processes are related to the action of waves!
Weathering – the breakdown of rocks into smaller particles
Erosion – the movement of weathered particles
Deposition – when eroded material is dropped and left behind
* Wave interactions with shorelines depend on:
1. Shape of the shoreline – more energy will hit headlands than bays!
2. Slope of the shoreline – a shallow slope will have more sand and material
deposited. Steeper slopes will have more erosion.
3. Type of rock material – small particles erode more easily and larger particles are
left behind. Also, less resistant rock types, such as sandstone, will erode faster
than more resistant rock types such as shale (example: the Red Rocks in St.
George’s will erode faster than the cliffs of Bell Island, Conception Bay)
4. Wave energy – more powerful waves will create more erosion
Waves have the power to erode shorelines and deposit sediment on the shore.
Tides work with waves and determine the range of shorelines that can be affected
by wave action!
Waves and Tides are the 2 main factors that shape shorelines!
Headland – a part of the coastline that comes out further into the ocean than the
land next to it
Bay – indented area of coastline usually between 2 headlands
* Wave energy is strongest at the headland and then spreads out as it reaches the
bays!
Sea caves – an area along a headland where ocean currents have carved a hole into
the land
Sea arches – an area along the headland where ocean currents have eroded entirely
through the headland
Sea stack – an area along the headland where ocean currents have eroded entirely
through the headland and the top has fallen in to create a separate piece or standing
rock separated from the headland
Beaches – areas where sediment has been deposited. They are constantly changing
because of waves and wind. They narrow in winter because of larger waves and are
wider in summer because of gentle waves.
Shoal – a place where the sea is shallower; often times it is a sand deposit and can
be seen above the water
Sand bar – a large ridge of sand formed by waves and currents
Technologies used to contain damage from tides and waves:
1. Breakwater – a long structure off the coast that decreases the intensity of waves
hitting the shoreline
2. Jetty or Wharf – structures that extend out from the coast to prevent drifting and
slows down shoreline erosion
3. Sea Walls – walls that run parallel with the sea, usually used in areas where the
sea level is rising
Tide – the daily rise and fall of the ocean
Tides are created by the gravitational pull of the moon and the spinning of the earth
Both the sun and moon influence the earth’s water, but the moon has the greater
influence because it is closer to the earth!
High tides occur on 2 sides of the earth at the same time – the side facing the moon
and the side opposite!
While these 2 sides experience high tide, the remaining portions of the earth will
experience low tides!
Tidal Range – the difference between the height of water at high tide and at low
tide. For example, if water was 7 m high at high tide and 2 m high at low tide, the
tidal range would be 5 m.
* A normal tidal range is approximately 0.6 m
* The largest tidal range in the world occurs in the Bay of Fundy, Canada. The
tidal range can get as high as 20 m!
There are 2 different tides:
1. Spring Tides – the largest tidal range happens when the Earth, moon and sun are
in a line. They occur because of the greatest gravitational pull of the moon.
Spring tides happen twice a month:
1. At full moon – earth is between the Moon and Sun
2. At new moon – when moon is between the earth and the sun
2. Neap Tides – smallest tidal range happens when the sun and moon are at right
angles to each other. Occur because of smaller gravitational pull of the moon
Neap tides happen twice a month:
1. First quarter of the moon – moon is on top of the earth
2. Third quarter of the moon – moon is below the earth
What is the difference between heat capacity and specific heat capacity?
Heat capacity – a measure of how long it takes a substance to heat up or cool down
Specific heat capacity – the amount of heat needed to raise the temperature of a
substance by 1 degree Celsius
* Water has a very high heat capacity, which means it takes a long time to warm
up and cool down. Therefore, oceans can store large amounts of heat and currents
that transport this heat to other parts of the world affecting their climate!
Convection – transfer of heat
Thermals – when the sun warms the surface of the ocean the heat is transferred to
the air above it through convection. Since the air is warm and less dense, it rises.
When it cools down, it becomes denser and sinks back down toward the ocean.
In the daytime, a cool breeze comes off the ocean, is warmed on land and when it
cools goes back to the ocean. The opposite is true at night where the cooler land
breeze blows out and is warmed over the ocean. This helps days from getting too
hot and nights from getting too cool.
How do oceans moderate climate?
Oceans stay warmer than land through the fall and winter because of its high heat
capacity. Also, the oceans stay cooler in the spring and summer. This prevents the
areas from being extremely hot in summer or cold in winter.
Newfoundland and Labrador Climate
Newfoundland and Labrador climate is regulated by the cold Labrador Current and
the warm Gulf Stream. This results in fog and quick changes in temperatures.
Fog – when the tropical, warm, moist air of the Gulf Stream blows over the cool
air of the Labrador Current, it cools and condenses as fog.
Temperature changes – our temperatures are controlled by the cold Labrador
Current transferring arctic winds and the warm Gulf Stream which transfers warm,
tropical winds. This moderates our climate making it not too cold and not too
warm! The local temperature will depend on which wind prevails!
El Nino and La Nina
Both are examples of global weather phenomenon and have opposite
characteristics as summarized in this chart.
El Nino
La Nina
Decrease in trade winds
Increase in trade winds
Warming of the ocean
Cooling of the ocean
More extreme drought or
flooding
Less drought or flooding
Decrease in marine
productivity
Increase in marine
productivity
Effect on Trade Winds
(winds that blow near the
equator and generally blow
toward the west)
Effect on Ocean
Temperature
Effect on weather
Effect on marine
productivity (ocean life)