OCE Ch. 7

Of the following gyres, which one(s) flow in a counterclockwise direction? Choose all that apply.

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

Coastal winds can cause upwelling or downwelling due to which of the following?

Ekman transport

Which of the following Atlantic Subtropical gyre boundary currents is split into two by a large landmass?

South Equatorial Current

The Ekman spiral is caused by:

the wind and the Coriolis effect.

Of the following statements about the Ekman spiral and Ekman transport, which is/are true? Choose all that apply.

-Ekman transport can result in both upwelling and downwelling. -In the deeper layers of the Ekman spiral, water can move in a direction opposite of the wind direction. -The Coriolis effect causes surface waters to move at an angle relative to the wind direction. -Ekman transport is to the right of the wind direction in the Northern Hemisphere.

Of the following surface currents, which one(s) transport large volumes of warm water to higher latitudes? Choose all that apply.

-Kuroshio Current -the Gulf Stream - Brazil Current

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?

-The Coriolis effect deflects ocean currents in the Southern Hemisphere to the left due to Earth's rotation. -Because the current is located in the Southern Hemisphere, the subtropical gyre pulls the current in a counterclockwise direction

Of the following locations, where would upwelling be expected to occur? Choose all that apply.

-in areas of diverging surface currents -where there is a sharp bend in the coastline -where seamounts or tablemounts are present

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 _____ 2. _______ 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 ______ occurs as surface waters move away from the coast. 4. Freezing seawater at _____ leads to increases in salinity and density.

1. North Atlantic Current 2. Thermohaline circulation 3. coastal upwelling 4. high latitudes

Ocean surface currents transfer about ________ of the total amount of heat from the tropics to the poles.

1/3

About what percent of the wind's energy is transferred to the ocean surface?

2

To produce a surface current of 1.6 knots in the open ocean, a steady wind of _____ knots would be required.

80

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.

Which of the following is the only current that completely circumscribes Earth?

Antarctic Circumpolar

The Benguela Current is an example of which of the following types of currents?

Eastern Boundary Current

The California Current is an example of which of the following types of currents?

Eastern Boundary Current

The observation that ships and icebergs in the southern hemisphere float to the left of the wind direction is an example of which of the following?

Ekman transport

The false-color map of sea surface temperatures shown below is an example of which of the following features?

El nino conditions

Which of the following currents contributes to the South Eastern United States being humid?

Gulf Stream

Which of the following methods are used to measure ocean surface currents indirectly?

Pressure gradients

The observation of a hill of water within all subtropical gyres is an example of which of the following?

Subtropical convergence

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

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

Judge the following sentence according to the criteria given below: India's Southwest Monsoon provides abundant precipitation BECAUSE the air brought in from the Indian Ocean is warm and full of moisture.

The assertion and the reason are both correct, and the reason is valid.

Judge the following sentence according to the criteria given below: The Equatorial Countercurrent is much better developed in the Pacific Ocean than in the Atlantic BECAUSE the Pacific Ocean basin is larger and more unobstructed than the Atlantic Ocean.

The assertion and the reason are both correct, and the reason is valid.

Judge the following sentence according to the criteria given below: The temperatures across the Atlantic at different latitudes are much higher in Europe than in North America BECAUSE of the effects of heat transfer from the Gulf Stream.

The assertion and the reason are both correct, and the reason is valid.

The Brazil Current is an example of which of the following types of currents?

Western Boundary Current

The Kuroshio (Japan) Current is an example of which of the following types of currents?

Western Boundary Current

Downwelling can result from __________.

converging surface currents

An increase in seawater density can be caused by a ________ in temperature or a/an ________ in salinity.

decrease; increase

Thermohaline circulation is driven by:

density differences.

Converging surface waters are areas of ________ and ________ productivity.

downwelling; low

During winter months, monsoon winds over the Indian Ocean:

flow from land to sea and are dry.

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

gravity and the Coriolis effect.

Which of the following currents is responsible for Peru becoming the largest producer of fish, from the sea, in the world?

humboldt current

Records indicate that the ocean is warming faster in the Arctic polar regions than elsewhere. If that continues, a possible consequence could be __________.

slowing of deep ocean circulation, resulting in lower oxygen levels in deep water

Between summer and winter, which of the following currents reverses its flow direction?

somali current

Coastal upwelling along the coast of Chile is a result of winds from the ________ turning towards the ________ due to Ekman transport.

south; left

The El Niño Southern Oscillation can best be described as:

the relationship between sea surface temperature and changing atmospheric pressure.

Deep ocean current movement is also known as __________.

thermohaline flow

In the southern hemisphere, the direction of Ekman transport is always:

to the left of the wind direction.

Equatorial currents are driven by the:

trade winds.

Surface waters are pushed away from land and replaced by nutrient-rich bottom water through:

upwelling

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

western boundary currents