OCE1001 Chapter 7

The Peru Current is a _______ current that flows _______.

Cold, North

Of the following statements about Ekman spiral and Ekman transport, which is/are true?

Connecting the arrows of water movement from the surface into deeper waters shows the spiral pattern. Ekman transport is to the right of the wind direction in the Northern Hemisphere. Because of the Coriolis effect, surface waters move at an angle to the wind direction. Within the Ekman spiral, deeper water can move in a direction exactly opposite of the wind direction. The two factors that affect the Ekman spiral are the wind direction and the Coriolis effect.

Subtropical gyres flow counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.

False

Vertical mixing of surface and deep seawater takes place in the low latitudes.

False

Which of the following statements about El Niño events is FALSE?

Fishing along Peru and Ecuador is much better.

The western boundary current of all subtropical gyres is intensified (it is fast, narrow, and deep).

Globally, there are five subtropical gyres. The centers of all subtropical gyres are associated with high atmospheric pressure. The western boundary current of all subtropical gyres is intensified (it is fast, narrow, and deep). 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.

The California Current is a ________ current that flows ________.

cold; south

Ekman transport is an average path of motion that, under ideal conditions, is at ________ to the wind's direction. Your Answer:

90 Degrees`

Of the following currents, which ones are parts of the South Atlantic Subtropical Gyre?

Benguela Current Brazil Current South Equatorial Current West Wind Drift

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

Deep-ocean currents contain water that is high in oxygen. Deep-ocean circulation is often referred to as thermohaline flow. 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 currents are important regulators of global climate. Deep-ocean currents are initiated by downwelling of cold, dense water near Antarctica and in the North Atlantic Ocean.

Of the following conditions, which is/are related to strong El Niño events?

Increased abundance of hurricanes in the eastern Pacific Ocean Higher sea levels in the eastern Pacific Ocean associated with warmer water Increase in sea surface temperatures and destruction of coral reefs in the eastern Pacific Ocean

Of the following gyres, which one(s) flow in a counterclockwise direction?

Northern Hemisphere Subpolar Gyres South Pacific Subtropical Gyre South Atlantic Subtropical Gyre Indian Ocean Subtropical Gyre

The West Wind Drift (Antarctic Circumpolar Current) is a part of which of the following subtropical gyres?

South Atlantic Subtropical Gyre South Pacific Subtropical Gyre Indian Ocean Subtropical Gyre

Which of the following currents does NOT belong with the others as part of the same gyre?

The Agulhas Current

The East Australian Current is the western boundary current of the South Pacific subtropical gyre.

True

The atmospheric circulation cell in the equatorial South Pacific created by the movement of air between high- and low-pressure regions is called the __________.

Walker cell

What is one of the first indications that an El Niño event may be occurring?

Warm water from near Australia migrates toward South America.

The Gulf Stream is a ________ current that flows ________.

Warm, North

The East Australian Current is a ________ current that flows ________.

Warm, South

Of the following surface currents, which one(s) flow generally from west to east?

West Wind Drift North Pacific Current Equatorial Counter Current

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

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

In relation to ocean circulation, a gyre is __________.

a large, circular-moving loop of surface water

Western intensification is ________.

caused by the rotational center of a gyre being located to the west of the ocean basin's geographic center, thus causing more water to flow within a narrower "channel"

Thermohaline flow is a term that describes ________.

deep-ocean current movement

A geostrophic current is one that (ideally) flows _______.

in a circular path around the central "hill" of a gyre

In subtropical gyres, western boundary currents have all of the following characteristics EXCEPT being __________.

relatively wide

Surface ocean currents are caused by ___________, whereas deep currents are the result of __________.

surface wind belts; density differences

The ocean's deep water is initially formed at the _________ and in _________ regions.

surface; subpolar

Of the following surface currents, which one(s) flow from south to north?

the Gulf Stream Kuroshio Current Peru Current

Which of the following is an example of a western boundary current of a subtropical gyre?

the Kuroshio Current