Oceanography Chapter 7

Which of the following is a western boundary current?

Brazil Current

Identify the mismatched pair.

Labrador Current, Humboldt Current

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

Equatorial currents are driven by the __________.

Trade winds

Thermohaline circulation is driven by:

density differences.

The El Niño Southern Oscillation can best be described as:

the relationship between sea surface temperature and changing atmospheric pressure.

To what depth in the ocean does the Ekman spiral extend?

-about 100 meters (330 feet)

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

Which of the following statements is most accurate about tsunami hazards and the number of people at risk?

A low tsunami hazard and a high number of people at risk are present along the coast of the eastern United States.

Which of the following statements about earthquakes and tsunami hazards is most accurate?

A relatively high number of earthquakes and the greatest tsunami hazard occur along the western coast of South America.

Westward intensification causes __________.

All of the above statements are the result of westward intensification

The arrangement of water masses in the southern Atlantic Ocean from the surface to the bottom is:

Antarctic Intermediate Water, North Atlantic Deep Water, Antarctic Bottom Water.

Which body of water is shown with the highest percentage of coastal pollution?

Baltic Sea

The worldwide effect of El Niño includes all of the following except __________.

Drought in the US Gulf coastal states

Surface currents affect about 90% of the world's ocean water. T/F

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 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.

Which of the following statements is true of surface ocean currents?

Surface currents form circular patterns in the major ocean basins called "gyres."

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. T/F

True

Deep ocean water can be enriched in oxygen when it is mixed with surface water. T/F

True

Deep ocean water masses have characteristic temperatures and salinities. T/F

True

Downwelling may be the result of winds blowing parallel to a coastline or the convergence of surface currents. T/F

True

Surface ocean currents are vertical currents in the water column that are density-driven. T/F

True

The densest ocean water is North Atlantic Deep Water. T/F

True

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

True

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

Match the term or person with the appropriate phrase. California Current

cold current, northern hemisphere, temperate latitudes

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 coastlines with the greatest tsunami hazard are most commonly associated with what type of plate boundary?

convergent

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

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

eddies

During winter months, monsoon winds over the Indian Ocean:

flow from land to sea and are dry.

Which type of current flow moves in a circular path around a subtropical convergence, reflecting Ekman transport, gravity, and the Coriolis effect?

geostrophic circulation

Which of the following two factors cause geostrophic circulation within a gyre?

gravity and the Coriolis effect.

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 temperature from normal conditions

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

meanders

Match the term or person with the appropriate phrase: Kuroshio Current

northern hemisphere, temperate latitudes, warm current

Sources of deep water in the ocean include all of the following except:

subtropical convergences

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

Under which conditions are droughts and wildfires common in Australia?

under El Niño conditions

geostrophic current

water flow driven by gravity and modified by the Coriolis force