oceanography. how much of the earth’s surface is water?
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Oceanography
How much of the Earth’s surface is
water?
71%
Name the oceans
ArcticAtlanticIndianPacific
Which ocean is the largest?
Pacific
Which is the smallest?
Arctic
Which is the deepest ocean?
Pacific
What are seas?
Smaller than oceans and re
partly surrounded by land or a chain
of oceans
What are they also called?
Gulfs
What is a characteristic of
an ocean?
Salinity – the saltiness
Where do the minerals come
from?
Weathering from rocks on land
Is the salinity the same in all parts
of the ocean?
No
Why not?
There is less in the colder regions because less
evaporation and more fresh water
melting
More in warmer climates because
there is more evaporation of
the water
What is water pressure?
The weight of the water pressing on
an object
What happens as you go deeper?
There is more pressure
because of more water on top of
you
What is the continental shelf?
The shallow area around the edge of the continent that extends into the
ocean
What is the Continental
slope?
A steep drop in land that extends from the continental shelf to the bottom of the
ocean
What is the Abyssal Plain?
The flattest part of the ocean
floor.
What is a ridge?
An underwater mountain range
What is a rift?
A deep valley in the ocean floor
What are waves?
The up and down movement of surface water
What causes waves?
The wind
Why?
Because water moves more
slowly than wind
Does water move forward very
much?
No – it stays in relatively the
same position
What are some other causes of
waves?
Earthquakes, volcanoes, and
extremely low air pressure
What is a tidal wave called?
Tsunami
How high can it get?
Over 100 feet
What is another problem during
storms?
Storm surge
What is it?
The continual increase of the level of the high
tide
What is a rogue wave?
It is a large wave coming in a
different direction than the others
What are currents?
A stream of water that flows through the ocean like a
river
What is special about this?
It moves water forward –
sometimes long distances
What are the different kinds of
currents?
SurfaceShoreline
rip
What are surface currents?
The flow of water across the surface of the ocean – usually caused by prevailing
winds
How large can they be?
Hundred kilometers wide by hundreds of meters deep
How does this affect the world?
It brings cold water to warm areas and
warm water to cold areas and impacts
the climate
What are shoreline currents?
Local currents that run along the coast – these can change
daily
What is a rip current?
A shoreline current that flows
away from the beach
How does this happen?
The water finds the easiest way away
from the beach and pulls through the
sandbars producing a strong current
What is a longshore current?
The water strikes the beach at an
angle and moves the water forward along the shore
What also causes the currents?
The rotation of the Earth and the
differences in temperature
How does the temperature
affect it?
Cold water sinks and warm water rises causes the water to change
places
What is tides?
The repeated rise and fall of the
level of the ocean
What is caused by?
Gravity of the moon
The End