Oceans

A convenient unit for reporting transport volume of the ocean's currents is the Sverdrup. A Sverdrup equals ______.

1 million cubic meters per second

Rank the following examples from the greatest volume of transport at the top to the least volume of transport at the bottom.

1. Antarctic 2. gulf stream 3. fresh water

Which of the following statements are true regarding a seasonal thermocline and a "permanent thermocline"? (Mark all that apply.)

- A "permanent thermocline" is not influenced by surface-water temperatures. - A "permanent thermocline" is generally deeper than a seasonal thermocline. - A seasonal thermocline often occurs at mid-latitudes.

Which of the following are characteristics of the Arctic Ocean? (Mark all that apply.)

- About one-third of its area is covered by extensive continental shelves. - Two basins, the Eurasian and the Canadian, occupy the central portion of the ocean.

Mark only the gyre currents of the North Pacific.

- California Current - Alaska Current - North Equatorial Current - North Pacific Current

Mark all of the major Pacific Ocean surface currents.

- California Current - North Equatorial Current - Kuroshio Current

Select all the characteristics that are true of the Indian Ocean.

- In the subtropics, a lens of warm, salty water occurs at the surface. - Water is brought into the Indian Ocean by the Antarctic Circumpolar Current.

Mark all of the following currents that are found in the North Atlantic.

- North Equatorial Current - Gulf Stream - Florida Current

Mark only the gyre currents of the South Pacific.

- South Equatorial Current - East Australian Current - Peru Current

Mark all the currents that are found in the Indian Ocean.

- South Equatorial Current - West Australia Current - Agulhas Current

Which of the following influence the depth of the mixing layer? (Mark all that apply.)

- The amount of turbulence caused by wind - The amount of turbulence caused by waves

Which of the following characteristics are true of the Pacific Ocean? (Mark all that apply.)

- The deeper water of the South Pacific Ocean is the water of the Antarctic circumpolar flow. - There is no large source of deep water similar to that found in the North Atlantic.

Match the term to its correct definition. A water type A water mass

A water type - Water samples that plot very near each other on a temperature-salinity diagram, possessing values within a narrow temperature and salinity range A water mass - A large body of water that has similar values of temperature and salinity throughout it

______ water moves slowly ______ through the South Atlantic ocean basins west of the Mid-Atlantic Ridge, but the ______ water sinks and moves ______ along the east side of the Atlantic.

Antarctic bottom; north; North Atlantic deep; south

The ______ Ocean is covered by extensive continental shelves and is made up of two basins, the Eurasian to the east and the Canadian to the west.

Arctic

Match the term to its correct definition. Convergence Divergence

Convergence - Refers to an area where ocean waters accumulate and where the water then sinks and undergoes downwelling Divergence - Refers to an area where surface waters are leaving; replacing them are upwelling deep waters

______ waters are more closely associated with downwelling, whereas _____ waters are more closely associated with upwelling.

Convergent; divergent

Match the zone to its correct characteristics. Downwelling zone Upwelling zone

Downwelling zone - Known for containing oxygen-rich water Upwelling zone - Known for containing low oxygen-content, nutrient-rich water

Water of the Arctic Ocean exits to the Atlantic by the ______ Current and the ______ Current.

East Greenland; Labrador

What does the image depict?

Ekman spiral

When surface winds blow, water movement is initiated; however, deep layers of water move more slowly because of low-friction coupling in the water resulting in a(n) ______.

Ekman spiral

The images portray seasonal changes that occur off the west coast of the United States. Match the image part (a or b) to the correct season.

a - Summer b- winter

As a result of Ekman transport, a portion of wind-driven surface water is deflected toward the center of each large gyre, causing ______.

a convergent lens of surface water to become elevated above the equilibrium sea level

The sea surface is elevated in the interior of the major current gyres because ______.

Ekman transport results in wind-driven surface water being deflected toward the center

True or false: The Arctic Ocean gyre is centered on the North Pole.

False

True or false: There are five major divergence zones in the ocean, including at the equator, two subtropical convergences, and two at about 50° N and S.

False

Match the temperature-versus-depth profile figures to the correct zone.

Image (a) - Mid-latitudes Image B - Low latitudes Image (c) - High latitudes

The Circumpolar Current flows around Earth because there are no landmasses to block it.

antarctic

The rate of deep-water eddy formation, the numbers of major eddies, their movements, and their life spans can be observed by instruments that ______.

are caught up in the eddies, moving with them, and sending out acoustic signals that can be monitored elsewhere

Each layer of the ocean receives its characteristic salinity, temperature, and density ______.

at the surface

The Arctic Ocean is supplied from the North Ocean by way of the Norwegian Current.

atlantic

The main Antarctic current is called the Antarctic Current.

circumpolar

Langmuir cells are ______.

composed of paired right- and left-handed helices that form shallow circulation convergence zones

When surface waters are driven together by the wind or up against a coast, a surface-water is formed, but when the wind blows surface waters away from an area or a coast, a surface-water occurs and water upwells from below.

convergence , divergence

The South Equatorial Current, West Australia Current, and Agulhas Current are all found in the ______ Ocean.

Indian

The ______ Ocean receives a fairly uniform mixture of Antarctic circumpolar water brought in by the Antarctic Circumpolar Current.

Indian

Match the term to the correct definition. Isopycnal Isothermal Isohaline

Isopycnal - When a water column has the same density over depth and has neutral stability Isothermal - When a water column has unchanging temperature over depth Isohaline - When a water column has constant salinity over depth

The ______ Current is faster and narrower than the ______ Current.

Kuroshio; California

______ form at the western boundary of the Gulf Stream, increasing in amplitude as they move downstream. The current pinches off the curve, forming a warm-water ______ that wanders into the cold-water zone.

Meanders; eddy

The source of the South Atlantic surface water is the ______.

North Atlantic deep water

Match the water mass of the Atlantic Ocean with its correct characteristics.

North Atlantic deep water - This water sinks and moves southward from the Norwegian Sea along the east side of the Atlantic. Antarctic bottom water - This water mass is the densest water in the ocean and sinks to the ocean floor. It moves slowly northward through the deep South Atlantic ocean basins west of the Mid-Atlantic Ridge. Mediterranean intermediate water - This water possesses an intermediate water density and flows out of the Strait of Gibraltar for about 1500 miles before being lost through modification and mixing.

The Ocean has very sluggish deep-water flows with conditions below 6600 ft being very uniform, and its residence time for deep water is about twice that of deep water in the Atlantic.

Pacific

The Oyashio Current, Alaska Current, and Humbolt Current are all found in the ______ Ocean.

Pacific

The ______ Sea marks the middle of an ocean gyre and is located in the central North Atlantic Ocean.

Sargasso

The South Equatorial Current, Brazil Current, and Benguela Current are all found in the ______.

South Atlantic

Match the water column type to the correct definition. Stable water column Unstable water column

Stable water column - A column of water where the density increases with depth Unstable water column - A column of water that consists of higher-density water on top of lower-density water

What seasonal change controls the surface flow of the Northern Hemisphere portion of the Indian Ocean?

Strong seasonal monsoons

Match the term to the correct example. Surface-water convergence Surface-water divergence

Surface-water convergence - Strong winds blow surface waters up against a rocky coastline Surface-water divergence - Inland winds blow surface waters away from a coast

The unit used to measure the transport volume of an ocean current is the ______.

Sverdrup

Why is it possible for the Antarctic Circumpolar Current to flow all the way around Antarctica without interruption?

There are no landmasses to block the Antarctic Circumpolar Current.

The Antarctic Circumpolar Current is also known as the ______.

West Wind Drift

Which of the following are true regarding the Sargasso Sea? (Mark all that apply.)

- The region is famous for a floating brown seaweed. - The water is clear and relatively warm.

Which of the following factors drive ocean surface currents? (Select all that apply.)

- Wind - Coriolis effect - Internal inertia

Which of the following contribute significantly to the internal mixing of the ocean's water masses? (Mark all that apply.)

- Wind-driven waves - Currents - Tides

Western intensification of currents traveling from low to high latitudes is related to the ______. (Mark all that apply.)

- changing strength and direction of the east-west wind field (trade winds and westerlies) with latitude - friction between landmasses and ocean water currents

Speed of current flow may not be directly related to surface wind speed but can be affected by the ______. (Mark all that apply.)

- depth and width of the current - presence of another current - rotation of Earth

Eddies eventually dissipate because of ______. (Mark all that apply.)

- fluid friction - losing their chemical and thermal identity - loss of energy of motion

Eddies ______. (Mark all that apply.)

- may maintain their physical identity for weeks or more as they wander about the oceans - each contain water with specific chemical and physical properties - can vary in size from 10 to several hundred kilometers in diameter

Langmuir cells ______. (Mark all that apply.)

- organize the distribution of suspended organic matter in convergence and divergence zones - are marked by windrows

Layers of ocean water are associated with ______.

depth zones: surface, intermediate, deep, and bottom

The Equatorial Countercurrent is ______ because of the unequal heating of the Northern and Southern Hemispheres.

displaced 5° north of the equator

A permanent zone of ______ occurs off the west coast of South America where the upwelling creates a productive fishery.

divergence

Areas of thermohaline circulation where water sinks are called zones and areas of rising waters are called zones.

downwelling; upwelling

The winds of the Indian Ocean change seasonally. In the summer in the Northern Hemisphere, the winds blow the surface water to the , and in the winter, they blow it to the .

east, west

Warm-water parcels from the Gulf Stream are able to enter cold-water regions in the form of ______.

eddies

When a narrow, fast-moving current moves into or through slower-moving water, the current oscillates and develops waves along its boundary that are known as meanders. The meanders break off to form , or pockets of water moving with a circular motion.

eddies

As a result of western intensification, geostrophic currents flowing on the western side of the gyre tend to be much ______ than on the eastern side.

faster, deeper, and narrower

The Kuroshio Current is ______ and ______ than the California Current.

faster; narrower

Deep-water eddies are monitored by using instruments that ______.

float at a mid-depth density layer

Resulting from western intensification, currents flowing on the western side of the gyre tend to be much faster, deeper, and narrower than on the eastern side.

geostrophic

Large, circular motion, wind-driven current systems are known as ______.

gyres

Seawater density is ______ to temperature and ______ to salinity.

inversely proportional; directly proportional

If a water column has the same density with depth, it is ______. If it has the same water temperature with depth, it is ______. If it has constant salinity over depth, it is ______.

isopycnal; isothermal; isohaline

Windrows, or streaks of foam and surface debris that are seen trailing off in the direction the wind is blowing, mark the convergence zones of shallow circulation cells known as cells.

langmuir

Gyres are ______.

large, circular motion, wind-driven current systems

In general, a water ______ refers to a larger body of water than that defined as a water ______, but both show similar values of temperature and salinity.

mass; type

Over the depth of an Ekman spiral, the water moves 90° to the right in the Hemisphere and 90° to the left in the Hemisphere.

northern, southern

The South Atlantic surface water flows in a ______ direction.

northward

Eddies are ______.

pockets of water moving in a circular motion

Circulation in the Arctic Ocean is driven by the ______, which produce a large, ______ gyre.

polar easterlies; clockwise

The surface current acted upon by the Coriolis effect is deflected to the ______ of the driving wind direction in the Northern Hemisphere and to the ______ in the Southern Hemisphere.

right; left

The total range of 75% of the ocean is between 34.5 and 35.0 parts per thousand (ppt).

salinity

Vertical columnar flows, approximately 5 inches in diameter, called ______, develop and mix water vertically, causing a stair-step salinity and temperature change with depth.

salt fingers

At low latitudes, surface temperatures are warm and constant throughout the year, so no ______ thermocline develops. At high latitudes (above 60°), there is no ______ thermocline.

seasonal; permanent

When the cross-sectional area of a current expands, the current ______.

slows down because flow is distributed over the width and depth of the current

If the density of water increases with depth, the water column from the surface to that depth is ______. If there is higher-density water on top of lower-density water, the water column is ______.

stable; unstable

Ocean ______ is(are) influenced by wind, atmospheric circulation, and Earth's rotation.

surface currents

Thermohaline circulation is a motion, or flow, of ocean water caused by variations in density due to differences in and .

temperature; salinity

The motion, or flow, of water in the ocean resulting from variations in water density is called ______.

thermohaline circulation

In the Pacific Ocean, the ______ move water away from Central and South America and pile it up against Asia, whereas the ______ move the water away from Asia and push it against the west coast of North America.

trade winds; westerlies

In the Pacific Ocean, the winds move water away from Central and South America and pile it up against Asia, whereas the move the water away from Asia and push it against the west coast of North America.

trade, westerlies

Major ocean currents ______ of water and are measured by the unit Sverdrup (Sv).

transport enormous volumes

The equatorial countercurrents are located on either side of 5° N, in the doldrums belt, as a result of ______.

unequal heating of the Northern and Southern Hemispheres

The Indonesian Throughflow transports large amounts of relatively ______ and ______ water to the Indian Ocean.

warm; fresh

In the image, variations in the average height of the sea surface are shown. Red indicates the highest elevations and green and blue the lowest. It is observed that the peak of water height is found on the ______ side of the ocean basins.

western

With western intensification, the mounds of water created by the Ekman transport have their highest point displaced to the ______ side of the gyres.

western

Western intensification creates a more steeply sloping surface over a shorter distance on the ______ side of the mound of water created by the Ekman transport and a more gently sloping sea surface over a longer distance on the ______ side of the mound.

western; eastern

The currents of the Indonesian Throughflow generally flow in a ______ direction.

westward