Download Grade 8 Science

Grade 8 Science
Unit 1 – Water Systems on Earth
Chapter 2: Oceans control the Water Cycle
Student Name: _______________________________
Oceans are important…
1. ______________________________________________________________________
2. ______________________________________________________________________
3. ______________________________________________________________________
4. ______________________________________________________________________
The Origin of Oceans:
1. Tectonic
Plates
Has helped to
determine where
____________ _____________
are located.
Has built ocean floor
along ___________________
ridges in areas where
plates ___________________
Tectonic plates move
changing the
___________________ of the
________________________.
2. Volcanic
Has helped build
Action
______________________
divides in areas where
plates have ____________
and ___________________
building occurs.
Water __________________ in volcanic materials
were released as __________________. It cooled,
_________________ and fell back to _______________.
This water collected in the _________________ parts
of the Earth’s surface.. The ________________________
3. Erosion
Has aided the further development of
________________________ drainage systems as
material is _________________ and ___________________
into the ocean _________________.
4. Glaciation A force of _______________ Glaciers move
in the development of materials
_______________________
_________________ the
drainage systems.
___________________.
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Researching the Ocean Floor
Technologies include:
1. _______________________________________
2. _______________________________________
3. _______________________________________
4. _______________________________________
5. _______________________________________
6. _______________________________________
Underwater Explorations:
 Shipwrecks
Ex: ___________________________ Discovered in ________________.
Technologies: Past and Present
Past
Present
Continental Margin
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Continental Shelf:
 The ______________________ part of the ______________________
between the __________________ and the ________________ of the
_________________.
Continental Slope:
 __________________________ shelves slope gradually away from
________________ before _________________________ drastically.
Abyssal Plain:
 Wide, _______________ features of the ____________.
 Formed of ___________________deposits of _____________________.
Where do these sediments come from?
_______________________________________:
 Long, __________________________ mountain chains formed
from _________________________ ___________________________
Canadian Organizations involved in Ocean Research:
1.
2.
3.
4.
________________________________________________________
________________________________________________________
________________________________________________________
________________________________________________________
Ocean Currents
 A ______________ amount of ocean ________________ that moves
in a particular and unchanging _______________________.
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2 Types of Ocean Currents:
1. ____________________ currents
 Flow in the top ________________________ m.
2. ____________________ currents
 Flow below ______________ m.
Surface Currents:
Factors that affect Surface Currents are:
1. Wind
__________ movement caused by
___________________ heating.
The _________________ of the moving ________
is transferred by friction to the ___________
molecules causing it to ______________.
2. Earth Rotation The Earth spins ________________________________________.
This spinning body deflects _______________
and _____________________ depending on
what side the _________________ they are on.
This alteration of ___________________ is
called the _____________________ _____________.
Clockwise in the ______________________
hemisphere and Counter Clockwise in the
______________________ hemisphere.
3. Shape of the
Moving _____________________ are forced to
Earth’s continents turn when they ______________ a _____________
surface.
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Deep Water Currents:
The most important influences are:
1. Water
temperature
2. Salinity
Not the _________________ at every
_____________________.
*Cold water is also ________________ dense
than __________________ water.
________________________ is less _______________
at the mouths of large __________________
due to the ________________ water entering
the _________________.
Fresh water also _________________ where
_____________________ and _____________________
melt and areas of high _____________________.
High amounts of _________________________
increases _____________________ as well as
_________________________.
Local Ocean Currents:
1. _______________________________________________________
 __________________ water
2. _______________________________________________________
 __________________ water
Waves:
 Large ________________________ set in motion by steady
____________________.
 Waves on the ________________________ of water are the result
of a _________________________ of ______________________ from
moving ____________ to the ______________________.
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Common Wave Features:
*As a wave approaches a ______________________, the wavelength
____________________ and the wave height _________________________.
2 Types of Waves:
1. ____________________
 ____________________ waves caused by ______________ and
______________________ far out in the ocean.
2. ____________________
 The ____________________ of water when a wave
________________________ onshore.
Tsunamis
 ____________________ waves that can be sent in
_________________ by ____________________________ on the ocean
floor, ________________________ or __________________________
eruptions near the shoreline.
 Can be very _____________________________.
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Tides
 The slow _______________ and ________________ of the ocean.
 The ___________________ and __________________ edges of a
beach are determined by the high- and low- _______________
mark.
 Tides are ____________________________ to the motion of the
________________ and the spinning of the __________________.
 The _________________ exerts a _____________________ force of
________________ than the ___________ due to its closer
________________________ to Earth.
2 Types of Tides:
1. ______________________ tide:
 Occur when the ____________________, _________________, and
__________________ are in a line.
 Causes extra __________________ and _________________ tides.
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2. _____________________ tide:
 Occur when the ____________ and the ________________ are at
____________________ angles to one another.
 Causes the _________________________ tidal movements. There
is little difference between _____________ and ____________
tides.
Tidal Range:
 The ____________________________ in _______________ between
a ______________ and a _____________ tide.
Shaping Our Shorelines:
 Waves have the power to ___________________ and
____________________ sediments on the __________________.
 Tides work with ________________ to determine the
_________________ of shoreline that can be
_____________________ by wave action.
Factors that affect the interaction of waves and tides on
the shoreline are:
1.
2.
3.
4.
____________________________________________________
____________________________________________________
____________________________________________________
____________________________________________________
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Shoreline Features:
 Wave energy is concentrated
into _______________________ and
spreads out as it reaches
_______________.
Shorelines can quickly change:
Example:
Intense wave action during:
 ____________________________________
 ____________________________________
Technologies to prevent/reduce the effects of wave action near
human development include:
1.
2.
3. Vegetation
4.
5. Coastal
reconfiguration
Offshore breakwaters __________________
the _____________________ of wave action in
___________________ waters and thereby
reduce ___________________ ________________.
A _________________ is a structure
extending into a _____________ of water,
which ____________________ a _______________
or _____________________ from the effects of
_____________________ and _______________.
--------------------------------------------------A ____________________ is a form of
_____________ and strong ________________
defense constructed on the inland part
of a _______________ to reduce the effects
of strong _______________.
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Comprehension Questions
1. What two features make up the continental margin?
___________________________________
___________________________________
2. What is an ocean current?
________________________________________________________________________
________________________________________________________________________
3. Explain how wind influences ocean currents.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
4. How does the Coriolis effect influence wave and wind
motion:
a) North of the equator? ____________________________________________
b) South of the equator? ____________________________________________
5. Explain the difference between surface current and deep
current.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
6. How is a breaker formed?
________________________________________________________________________
________________________________________________________________________
7. How are headlands and bays created?
________________________________________________________________________
________________________________________________________________________
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8. What causes a tsunami?
________________________________________________________________________
________________________________________________________________________
9. What is the difference between a spring tide and a neap tide?
________________________________________________________________________
________________________________________________________________________
10. Why are shorelines in a constant state of change?
________________________________________________________________________
________________________________________________________________________
11. How does a tidal wave differ from a tsunami?
________________________________________________________________________
________________________________________________________________________
12. When the Sun heats the surface of an ocean in some
regions, large amounts of water evaporate. How does this
evaporation affect the salinity of the water near the surface?
How does this change in salinity affect the motion of the water?
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
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