Ocean Circulation Mastering Assignment
When a meander from the Gulf Stream pinches off into the warm water south of the current, the eddy is called a __________.
cold core eddy or ring
A large system of rotating ocean currents, usually driven by the major wind belts, is called a(n) __________.
gyre
Which of the following is not an eastern boundary current?
Gulf stream
Warm ocean currents ___.
are warmer than the surrounding water
Surface ocean currents ___.
1. are influenced by the Coriolis effect 2. form large rotating gyres in the major ocean basins 3. are driven by winds
Western boundary currents such as the Gulf Stream transport warm water from the tropics towards higher latitudes.
True
The subtropical gyres ___.
play a large role in climate
An eastern boundary current is generally narrow and swift.
False
The Gulf Stream transports warm water into the __________.
North Atlantic
High amounts of _____ caused one of the items to _____.
sugar; sink
The Ekman spiral is caused by:
the wind and the Coriolis effect
Of the following surface currents, which one(s) flow from south to north?
1. Peru Current 2. Kuroshio Current 3. the Gulf Stream
Of the following surface currents, which one(s) flow generally from west to east?
1.Equatorial Counter Current 2. West Wind Drift 3. North Pacific Current
Of the following statements about Ekman spiral and Ekman transport, which is/are true?
A. Ekman transport is to the right of the wind direction in the Northern Hemisphere. B. Connecting the arrows of water movement from the surface into deeper waters shows the spiral pattern. C. The two factors that affect the Ekman spiral are the wind direction and the Coriolis effect. D. Within the Ekman spiral, deeper water can move in a direction exactly opposite of the wind direction. E. Because of the Coriolis effect, surface waters move at an angle to the wind direction.
Ocean frontal systems that spin off from currents such as the Gulf Stream, akin to atmospheric storms, are known as __________.
Eddies
One of the world's most powerful currents, located off the east coast of the United States, is the __________.
Gulf Stream
The current in the northwestern part of the North Atlantic Subtropical Gyre that transports warm water toward the North Atlantic is called the __________.
Gulf Stream
What happened to the Styrofoam cup that was subjected to the high pressure of the deep ocean?
It became a miniature-sized cup.
What is the Walker Circulation Cell?
It is the path that air takes as it moves from high to low pressure, and back to high pressure, in the South Pacific under normal conditions.
Fluctuations in the flow of the Gulf Stream current result in curving loops of water known as __________.
Meanders
Palm trees associated with the subtropics can be found at the northern tip of the British Isles in Scotland. This is due to the transfer of heat from the
North Atlantic Current
A deep and powerful southward subsurface current that flows under the Gulf Stream in the North Atlantic is the __________.
North Atlantic Deep Water
Sources of deep water in the ocean include all of the following except:
Subtropical convergences
What would you expect weather to be like on the eastern coast of Australia if the western coast of South America were experiencing unusually warm, wet weather?
The eastern coast of Australia would be experiencing unusually dry weather.
Why does upwelling occur along the west coast of South America under normal conditions?
Winds moving westward in the South Pacific drive ocean currents toward the west; deep water rises to replace water driven westward.
What common household item is used in this video to demonstrate the Ekman spiral?
a deck of playing cards
The thermocline is _________________.
a steep temperature gradient in the ocean that separates deeper cold water from warmer upper water
To what depth in the ocean does the Ekman spiral extend?
about 100 meters (330 feet)
Compared to western boundary currents, eastern boundary currents are:
broad and slow
The loss of heat from the ocean surface, resulting in a lowered temperature, causes ocean water to become __________.
denser
Equatorial currents that are part of the subtropical gyres flow ___. Equatorial counter currents between the gyres flow ___ .
east to west; west to east
Freezing seawater at ________ leads to increases in salinity and density.
high latitudes
What is the overall effect of the stronger than normal trade winds typical of La Niña conditions?
lowering of the South Pacific ocean temperature from normal conditions
In the Northern Hemisphere, the Ekman spiral moves layers of water to the _____ of the wind direction and Ekman transport (the overall direction of water movement) is to the _____.
right; right
As shown in the video, the regular version of the item _____ and the diet version _____.
sank; floated
Thermohaline circulation in the ocean is driven primarily by differences in __________ and __________ among water masses.
temperature; salinity
What is the Southern Oscillation?
the swapping of high and low pressure zones in the South Pacific under El Niño conditions
is caused by density changes near the poles and equator.
thermohaline circulation
Under which conditions are droughts and wildfires common in Australia?
under El Niño conditions
Recall that global winds impact the direction of surface ocean currents. Examine the map below showing the Atlantic Ocean off the west coast of Africa. The direction of the surface current and the prevailing wind do not coincide. What can explain this discrepancy?
Because the current is located in the Southern Hemisphere, the subtropical gyre pulls the current in a counterclockwise direction. AND The Coriolis effect deflects ocean currents in the Southern Hemisphere to the left due to Earth's rotation.
Waters along the California coast are colder than those along the mid-Atlantic shore of the US because ________ occurs as surface waters move away from the coast.
coastal upwelling
Which direction do ocean currents in the South Pacific move under El Niño conditions?
eastward
Cool ocean currents ___.
generally flow from high latitudes towards the equator
What common household items are used in this video to demonstrate the properties of different water masses?
regular and diet sodas
Deep ocean currants
result from changes in water density (due to temperature and salt content)