Question 1

During its time in the deep ocean, deep water can become enriched in oxygen.

Accepted Answer

As surface waters cool at high latitudes, they become denser and sink, carrying oxygen from the surface into the deep ocean.

Question 2

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

Accepted Answer

This statement is true. Deep ocean currents are driven by differences in water density, especially differences in temperature and salinity. Cold, dense water at the poles sinks and flows towards the equator, while warmer, less dense water at the equator rises and flows towards the poles. This movement of cold, dense water away from the poles is an important part of the global ocean circulation system.

Question 3

Monsoons are seasonal pressure systems that develop at lower latitudes over continents, which cause changes in seasonal winds and precipitation patterns.

Accepted Answer

Monsoons are indeed seasonal pressure systems that develop at lower latitudes over continents, leading to changes in seasonal winds and precipitation patterns.

Question 4

The main current in Antarctic waters is the Antarctic Circumpolar Current, also called the West Wind Drift.

Accepted Answer

The Antarctic Circumpolar Current, also known as the West Wind Drift, is the main current in Antarctic waters. It circles the continent in a clockwise direction and is driven by the westerly winds.

Question 5

Surface ocean currents are driven primarily by ________ and modified by ________.
A)density differences; the Coriolis effect and land
B)density differences; differences in salinity and temperature
C)latitude; differences in salinity and land
D)wind; the Coriolis effect and land
E)wind; gravity and density

Accepted Answer

Surface ocean currents are primarily driven by wind, which creates friction on the water surface, causing it to move. However, the specific direction and path of the current is also influenced by the Coriolis effect (due to the rotation of the Earth) and land masses. Density differences and differences in salinity and temperature can also play a role in modifying ocean currents, but they are not the primary driving force.

Question 6

Which of the following is not an eastern boundary current?
A)California Current
B)Canary Current
C)Gulf Stream
D)Peru Current
E)W) Australian Current

Accepted Answer

The Gulf Stream is a western boundary current, not an eastern boundary current. Eastern boundary currents, like the California, Canary, and Peru Currents, are typically cold, slow, and shallow, flowing from the poles towards the equator along the eastern edges of ocean basins. The Gulf Stream, in contrast, is a warm, fast, and deep current that flows from the equator towards the poles along the western edge of the North Atlantic Ocean.

Question 7

Thermohaline circulation is wind-driven.

Accepted Answer

Thermohaline circulation, also known as the ocean conveyor belt, is driven by differences in temperature and salinity, not wind. The circulation is caused by the sinking of dense, cold, and salty water in the polar regions and the upwelling of warmer, less dense water in the equatorial regions.

Question 8

Deep ocean water masses have characteristic temperatures and salinities.

Accepted Answer

Deep ocean water masses do have characteristic temperatures and salinities, which can vary depending on factors such as depth, location, and circulation patterns.

Question 9

Equatorial currents are driven by the:
A)Coriolis force.
B)density.
C)Ekman transport.
D)trade winds.
E)westerlies.

Accepted Answer

Equatorial currents are primarily driven by the trade winds, which blow consistently from east to west near the equator, pushing surface water in the same direction.

Question 10

Which of the following statements is true of surface ocean currents?
A)Surface currents concentrate warm water in the center of the gyre at mid latitudes.
B)Surface currents form circular patterns in the major ocean basins called "gyres."
C)Surface currents occur within and below the pycnocline.
D)Surface currents transport cold water toward the poles.
E)Surface currents transport warm water toward the equator.

Accepted Answer

Surface currents form circular patterns in the major ocean basins called "gyres." This is because of the combination of the Coriolis effect and wind patterns.

Question 11

Identify the mismatched pair from the choices below.
A)Agulhas Current, West Australia Current
B)Brazil Current, Benguela Current
C)Canary Current, Gulf Stream
D)Kuroshio Current, California Current
E)Labrador Current, Humboldt Current

Accepted Answer

The mismatched pair is E) Labrador Current, Humboldt Current. The Labrador Current is a cold current in the North Atlantic Ocean, while the Humboldt Current, also known as the Peru Current, is a cold, low-salinity ocean current that flows north along the western coast of South America. The other pairs match a warm current with a cold current from different oceans or regions.

Question 12

Which of the following is a western boundary current?
A)Benguela Current
B)Brazil Current
C)Canary Current
D)California Current
E)Peru Current

Accepted Answer

The Brazil Current is a western boundary current that flows southward along the eastern coast of South America. It is a warm current that transports tropical waters from the Caribbean Sea southward, and it is one of the western boundary currents that make up the South Atlantic subtropical gyre.

Question 13

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

Accepted Answer

Downwelling is indeed caused by these two factors - winds blowing parallel to a coastline or the convergence of surface currents. This causes surface waters to pile up and sink downward, carrying nutrients and oxygen to deeper layers of the ocean.

Question 14

Compared to western boundary currents, eastern boundary currents are:
A)broad and deep.
B)broad and slow.
C)deep and swift.
D)narrow and deep.
E)shallow and swift.

Accepted Answer

Eastern boundary currents are characterized by being broader and slower compared to the western boundary currents. This is due to the Coriolis effect and the way water is distributed across ocean basins.

Question 15

The densest ocean water is North Atlantic Deep Water.

Accepted Answer

The densest ocean water is actually Antarctic Bottom Water (AABW), which forms in the Southern Ocean surrounding Antarctica, primarily due to its very low temperatures and high salinity.

Question 16

Compared to an eastern boundary current in a gyre, which of the following statements is true for a western boundary current?
A)deeper current
B)increased current velocity
C)warmer water
D)narrower current
E)All of the above statements are true of western boundary currents.

Accepted Answer

Western boundary currents in a gyre are narrower, deeper, faster, and warmer than the eastern boundary currents due to the Coriolis effect. The Coriolis effect in the Northern Hemisphere causes water to move to the right, causing the western boundary current to be more intense than the eastern boundary current, which moves to the left. These differences in intensity lead to the differences in temperature and depth of the currents. Therefore, all of the statements mentioned in the options are true for western boundary currents.

Question 17

The West Wind Drift occurs at 60°N around the Arctic Circle.

Accepted Answer

The West Wind Drift, also known as the Antarctic Circumpolar Current, actually occurs around the Antarctic Circle at 60°S, not the Arctic Circle at 60°N.

Question 18

Deep ocean water does not travel across the equator.

Accepted Answer

Deep ocean currents, part of the thermohaline circulation, can and do travel across the equator, connecting the world's oceans in a global conveyor belt of water movement.

Question 19

The Gulf Stream moves water away from the equator; the Benguela Current moves some of this same water back toward the equator.

Accepted Answer

The Gulf Stream moves warm water from the Gulf of Mexico and the Caribbean Sea towards the North Atlantic, while the Benguela Current moves cool water from the southern Atlantic towards the equator along the west coast of Africa. They do not flow in opposite directions.

Question 20

Deep ocean currents are driven primarily by ________ and modified by ________.
A)density differences; the Coriolis effect and land
B)density differences; differences in salinity and temperature
C)latitude; differences in salinity and land
D)wind; the Coriolis effect and land
E)wind; gravity and density

Accepted Answer

Deep ocean currents are mainly driven by differences in water density, which is influenced by variations in temperature and salinity. However, these currents are also modified by other factors, including the Coriolis effect and differences in pressure gradients caused by variations in gravity. Land masses can also play a role by blocking or diverting ocean currents. Wind, on the other hand, primarily affects surface ocean currents rather than the deeper currents. Therefore, option B is the best choice as it correctly identifies density differences as the primary driver of deep ocean currents and mentions differences in temperature and salinity as modifiying factors.

Quiz 7: Ocean Circulation

During its time in the deep ocean, deep water can become enriched in oxygen.

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

Monsoons are seasonal pressure systems that develop at lower latitudes over continents, which cause changes in seasonal winds and precipitation patterns.

The main current in Antarctic waters is the Antarctic Circumpolar Current, also called the West Wind Drift.

Surface ocean currents are driven primarily by and modified by .

Which of the following is not an eastern boundary current?

Thermohaline circulation is wind-driven.

Deep ocean water masses have characteristic temperatures and salinities.

Equatorial currents are driven by the:

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

Identify the mismatched pair from the choices below.

Which of the following is a western boundary current?

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

Compared to western boundary currents, eastern boundary currents are:

The densest ocean water is North Atlantic Deep Water.

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

The West Wind Drift occurs at 60°N around the Arctic Circle.

Deep ocean water does not travel across the equator.

The Gulf Stream moves water away from the equator; the Benguela Current moves some of this same water back toward the equator.

Deep ocean currents are driven primarily by and modified by .