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Warm ocean currents ___.

are warmer than the surrounding water

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

The loss of heat from the ocean surface, resulting in a lowered temperature, causes ocean water to become __________.

denser

Deep ocean currents are driven primarily by ________ .

density differences

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

A large system of rotating ocean currents, usually driven by the major wind belts, is called a(n) __________.

gyre

What is the overall effect of the stronger than normal trade winds typical of La Niña conditions?

lowering of the south pacific ocean temp from normal conditions

Fluctuations in the flow of the Gulf Stream current result in curving loops of water known as __________.

meanders

High amounts of _____ caused one of the items to _____.

sugar; sink

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

Deep ocean current movement is also known as __________.

thermohaline flow

Dynamic topography can be used to determine current direction and velocity.

true

Under which conditions are droughts and wildfires common in Australia?

under El Niño conditions

Surface ocean currents are driven primarily by ________ and modified by ________.

wind; the Coriolis effect and land

Recall that global winds impact the direction of surface ocean currents. Examine the following map 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. -The Coriolis effect deflects ocean currents in the Southern Hemisphere to the left due to Earth's rotation.

Of the following statements about deep-ocean currents, which is/are true?

-Deep-ocean currents contain water that is high in oxygen. -The volume of water involved in the downward movement of deep-ocean currents is equal to the flow of 100 Amazon-sized rivers. -Deep-ocean circulation is often referred to as thermohaline flow. -Deep-ocean currents are initiated by downwelling of cold, dense water near Antarctica and in the North Atlantic Ocean. -Deep-ocean currents are important regulators of global climate.

Of the following locations, where would upwelling be expected to occur?

-In areas of offshore winds -In areas of diverging surface currents, such as along the equator -Where there is a sharp bend in a coastline -Where there is a shallowly submerged sea floor obstruction, such as a tablemount-

Of the following statements about subtropical gyres, which is/are true?

-The western boundary current of all subtropical gyres is intensified (it is fast, narrow, and deep). -The centers of all subtropical gyres are associated with high atmospheric pressure. -Globally, there are five subtropical gyres. -The rotation of each subtropical gyre causes a "hill" of water to pile up within it. -There are four main surface currents in each subtropical gyre.

Surface ocean currents ___.

-are driven by winds -form large rotating gyres in the major ocean basins -are influenced by Coriolis effect

Using this image of the waters adjacent to the East Coast of the United States, match the correct letter to each of the following.

1. A: Color for cold water 2. C: Color for warm water 3. D: Warm core ring(s) 4. B: Cold core ring(s)

The following block diagram shows coastlines in the Northern Hemisphere that are influenced by coastal winds (not shown). Based on the flow of surface waters due to Ekman transport, identify the correct coastal wind direction in each diagram.

1. B: Wind blowing parallel to the coast and toward the bottom of the diagram 2. A: Wind blowing parallel to the coast and toward the top of the diagram

The image below is a block diagram showing the Pacific Ocean during an El Niño event. Correctly match the letters with the corresponding features.

1. C: High atmospheric pressure 2. B: Walker Circulation Cell (reversed direction) 3. D: Low atmospheric pressure 4. E: Pacific Warm Pool 5. A: Thermocline

Use the map of Pacific and Atlantic Ocean currents shown below to correctly identify the following ocean currents and gyres.

1. G: Peru Current 2. B: Subtropical gyre 3. C: Gulf Stream Current 4. F: Canary Current 5. D: Benguela Current 6. E: California Current 7. A: Subpolar gyre 8. I: Brazil Current 9. H: Antarctic Circumpolar Current (West Wind Drift)

The actual movement of surface water due to Ekman transport in the Northern Hemisphere is about __________.

45° to the right of wind direction

Western intensification causes:

All the above effects are the result of western intensification.

Compared to an eastern boundary current in a gyre, which of the following statements is true for a western boundary current?

All the above statements are true of western boundary currents

An eastern boundary current is generally narrow and swift.

False

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.

The Gulf Stream transports warm water into the __________.

North Atlantic

A deep and powerful southward subsurface current that flows under the Gulf Stream in the North Atlantic is the __________.

North Atlantic Deep Water

The deepest and most dense water mass in the world ocean is formed in the __________________.

Southern Ocean

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

Deep ocean currents often move cold, dense water away from the poles.

True

Deep ocean water masses have characteristic temperatures and salinities.

True

The five subtropical gyres exhibit geostrophic flow, related to pressure gradients, friction, and the Coriolis effect.

True

Western boundary currents such as the Gulf Stream transport warm water from the tropics towards higher latitudes.

True

The largest of the great ocean surface currents is the __________.

West Wind Drift

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

The thermocline is _________________.

a steep temperature gradient in the ocean that separates deeper cold water from warmer upper water

During a strong El Nino event, the news media might be expected to cover __________.

a tropical cyclone in Hawaii or Tahiti

The diagram below shows a generalized cross-sectional view across the Atlantic Ocean. Correctly match the letters with the corresponding water masses and associated features.

1. C: Seasonally warm water 2. G: Upwelling 3. B: Warmest water 4. E: Antarctic Intermediate Water 5. D: Antarctic Bottom Water 6. F: North Atlantic Deep Water 7. A: Thermocline and pycnocline

Deep-ocean currents are caused by changes in the density of seawater (referred to as thermohaline circulation), caused by changes in temperature or salinity. This causes a conveyor belt-like movement of water throughout the oceans. This conveyor belt of currents is a principal mechanism for the planet to distribute heat from the equator to the poles, which also influences climate patterns.

1. 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. 2. Thermohaline circulation is caused by density changes near the poles and equator. 3. Waters along the California coast are colder than those along the mid-Atlantic shore of the U.S. because coastal upwelling occurs as surface waters move away from the coast. 4. Freezing seawater at high latitudes leads to increases in salinity and density.

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

Downwelling can result from __________.

converging surface currents

Equatorial currents that are part of the subtropical gyres flow ___. Equatorial counter currents between the gyres flow ___ .

east to west; west to east

Ocean frontal systems that spin off from currents such as the Gulf Stream, akin to atmospheric storms, are known as __________.

eddies

The subtropical gyres ___.

play a large role in climate

What common household items are used in this video to demonstrate the properties of different water masses?

regular and diet sodas

Deep ocean currents ___.

result from changes in water density (due to temperature and salt content)

As shown in the video, the regular version of the item _____ and the diet version _____.

sank; floated

Warm core rings and cold core rings are associated with __________.

western boundary currents