-
The movement of ocean water is driven by differences in
density and temperature, by wind, and by the moon’s gravity.
-
Ocean water contains streamlike movements of water called
ocean currents.
-
Horizontal, streamlike movements of water that occur at or near the surface of the ocean are called
surface currents
-
one of the longest surface currents—it transports 25 times more water than all the rivers in the world.
Gulf Stream
-
Surface currents are controlled by three factors:
global winds, the Coriolis effect, and continental deflections
-
The apparent curving of moving objects from a straight path due to the Earth’s rotation is called
the Coriolis effect
-
When surface currents meet continents,
the currents deflect, or change direction
-
Streamlike movements of ocean water located far below the surface are called
deep currents
-
deep currents form in parts of the ocean where water density
increases
-
is the amount of matter in a given space, or volume.
Density
-
The density of ocean water is affected by
temperature and salinity—a measure of the amount of dissolved salts or solids in a liquid.
-
Both decreasing the temperature of ocean water and increasing the water’s salinity increase
wters density
-
Water density depends on
temperature and salinity
-
is a process in which cold, nutrient-rich water from the deep ocean rises to the surface and replaces warm surface water,
Upwelling
-
Every 2 to 12 years, the South Pacific trade winds move less warm water to the western Pacific than they usually do
El Niño
-
is a periodic change in the eastern Pacific Ocean in which the surface-water temperature becomes unusually cool
La Niña
-
A __________ is the highest point of a wave.
crest
-
A _________ is the lowest point of a wave.
trough
-
The distance between two adjacent wave crests or wave troughs is a
wavelength
-
The vertical distance between the crest and trough of a wave is called the
wave height
-
Deep water waves become shallow water waves when they reach deeps of
less than one half of their wave length.
-
his movement of water, which carries sand, rock particles, and plankton away from the shore, is called an
undertow
-
When waves hit the shore at an angle, they cause water to move along the shore in a current called a
longshore current
-
are white, foaming waves with very steep crests that break in the open ocean before the waves get close to the shore.
Whitecaps
-
are rolling waves that move steadily across the ocean.
Swells
-
are waves that form when a large volume of ocean water is suddenly moved up or down.
Tsunamis
-
A local rise in sea level near the shore that is caused by strong winds from a storm, such as a hurricane, is called a
storm surge
-
are caused by the gravitational forces of the moon and sun on the Earth.
Tides
-
The ________ _______ is the main force behind the tides.
moon’s gravity
-
The four different types of tides are:
high tides, low tides, spring tides, and neap tides.
|
|