Oceanography Ch. 7

Thermohaline circulation is driven by: (a) density. (b) gravity. (c) latitude. (d) temperature. (e) wind.

A. density

Subsurface currents are driven mainly by ___________. (a) wind (b) the rotation of the Earth (c) density differences (d) solar storms (e) wind drag

C. density differences

Scientists have concluded that deep Pacific Ocean water is old is due to its low __________. (a) density (b) nutrient levels (c) oxygen levels (d) salinity (e) temperature

C. oxygen levels

Thermohaline circulation patterns are caused by variations in ___________. (a) evaporation (b) precipitation (c) land runoff (d) heat exchange with the atmosphere (e) all of the above

E. All of the above

The source of some deep ocean water masses can be identified by the amount of dissolved oxygen in the water mass. (a) True (b) False

A. True

Thermohaline circulation is the dominant type of water flow in the ocean. (a) True (b) False

A. True

Western boundary currents can have well-defined edges. (a) True (b) False

A. True

Western boundary currents such as the Gulf Stream transport warm water from the tropics towards higher latitudes. (a) True (b) False

A. True

Replacement of water coming from the bottom to the top of the water column is called __________. (a) Ekman transport (b) geostrophic flow (c) upwelling (d) downwelling

C. Upwelling

All are true of the Antarctic Circumpolar Current except: (a) the Antarctic Circumpolar Current contributes to the development of Antarctic bottom water in the Weddell Sea. (b) the Antarctic Circumpolar Current contributes to upwelling off the Antarctic coast producing an area of high primary productivity in Antarctic summer. (c) the Antarctic Circumpolar Current flows in a counterclockwise direction around the southern hemisphere at 60º S latitude. (d) the Antarctic Circumpolar Current flows in the opposite direction to the East Wind Drift, a current the flows close to the Antarctic continent. (e) the Antarctic Circumpolar Current is created by the prevailing winds at that latitude

...

Sources of deep water in the ocean include all of the following except: (a) southern subpolar latitudes. (b) northern subpolar latitudes. (c) subtropical convergences. (d) Arctic convergence. (e) Antarctic convergence.

...

San Francisco's characteristic cold and foggy weather is caused by a ___________. (a) cold eastern boundary current (b) warm eastern boundary current (c) cold western boundary current (d) warm western boundary current

A. Cold eastern boundary current

When a meander from the Gulf Stream pinches off and isolates a body of water within the center of the North Atlantic gyre, the body of water is called a __________. (a) cold-core ring (b) cyclonic circulation (c) geostrophic circulation (d) Langmuir cell (e) warm-core ring

A. Cold-core ring

The characteristics of western boundary currents are a result of ___________. (a) Coriolis deflection. (b) higher wind speeds on the western edge of oceans. (c) deeper continental shelf areas on the western edge of oceans. (d) greater freshwater runoff from the adjacent land masses, which stabilizes the water column. (e) the rotation of the earth, which presses water against the western edge of the ocean basins.

A. Coriolis deflection.

Transport of water to the left or right of the wind direction is called __________. (a) Ekman transport (b) geostrophic flow (c) upwelling (d) downwelling

A. Ekman transport

During winter months, monsoon winds over the Indian Ocean __________. (a) flow from land to sea and are dry (b) flow from land to sea and are wet (c) flow from sea to land and are dry (d) flow from sea to land and are wet (e) the direction of airflow is unchanged but precipitation increases

A. Flow from land to sea and are dry

The El Niño Southern Oscillation can best be described as __________. (a) relative changes between two different atmospheric pressure systems (b) the relationship between sea surface temperature and high altitude pressure (c) tidal differences between coastal Peru and Darwin, Australia (d) variation in wind speed over the Pacific Ocean (e) wind speed and wind direction differences along the equator

A. Relative changes between two different atmospheric pressure systems

All deep water in ocean basins originates in the Atlantic Ocean. (a) True (b) False

A. True

Deep ocean currents often move cold, dense water away from the poles. (a) True (b) False

A. True

Deep ocean water masses have characteristic temperatures and salinities. (a) True (b) False

A. True

Downwelling may be the result of winds blowing parallel to a coastline. (a) True (b) False

A. True

During its time in the deep ocean, deep water can become enriched in oxygen. (a) True (b) False

A. True

Dynamic topography can be used to compute current direction and velocity. (a) True (b) False

A. True

In the northern hemisphere, Ekman transport pushes surface water to the right of the wind direction. (a) True (b) False

A. True

The circular movement of surface water currents driven by the major wind belts are called gyres (a) True (b) False

A. True

The circular pattern of surface water currents is called a gyre. (a) True (b) False

A. True

The five subtropical gyres exhibit geostrophic flow, related to pressure gradients, friction, and the Coriolis effect. (a) True (b) False

A. True

The largest current by volume in the oceans is the Antarctic Circumpolar Current. (a) True (b) False

A. True

The main current in Antarctic waters is the Antarctic Circumpolar Current, also called the West Wind Drift. (a) True (b) False

A. True

When near-surface water is moved offshore by Ekman transport, water from below replaces it in a process known as ___________. (a) upwelling (b) downwelling (c) Langmuir circulation (d) Franklin eddies (e) occlusion

A. Upwelling

The Gulf Stream in the northwestern Atlantic Ocean is an example of a __________ current. (a) warm-water, western boundary (b) warm-water, eastern boundary (c) transverse (d) cold-water, western boundary (e) cold-water, eastern boundary

A. Warm-water, western boundary

The Kuroshio Current in the northwestern Pacific Ocean is an example of a __________ current. (a) warm-water, western boundary (b) warm-water, eastern boundary (c) transverse (d) cold-water, western boundary (e) cold-water, eastern boundary

A. Warm-water, western boundary

Deep ocean water in the Indian Ocean includes Red Sea water which has __________. (a) high salinity and low oxygen (b) high salinity and low temperature (c) low salinity and low oxygen (d) low temperature and high oxygen (e) low temperature and low salinity

A. high salinity and low oxygen

Currents are named for the direction ___________. (a) in which they are going (b) from which they are coming

A. in which they are going

As the salinity of water increases, its density ___________. (a) increases (b) decreases

A. increases

Which current within a Northern Hemisphere gyre would you expect to have the lowest salinity and temperature? (a) a western boundary current (b) an eastern boundary current (c) a southern boundary current (d) a northern boundary current (e) All of these currents would be about equal in temperature and salinity.

B. An eastern boundary current

Which of the following is a western boundary current? (a) Benguela Current (b) Brazil Current (c) Canary Current (d) California Current (e) Peru Current

B. Brazil current

The densest water in ocean currents is the ___________. (a) warmest and saltiest (b) coldest and saltiest (c) warmest and freshest (d) coldest and freshest

B. Coldest and saltiest

When winds blow parallel to the coast, such that Ekman transport drives water against the land, surface water sinks in the process known as ___________. (a) upwelling (b) downwelling (c) Langmuir circulation (d) Franklin eddies (e) occlusion

B. Downwelling

Compared to a western boundary current, which of the following statements is true for an eastern boundary current? (a) Eastern boundary currents are broad and deep. (b) Eastern boundary currents are broad and slow. (c) Eastern boundary currents are deep and swift. (d) Eastern boundary currents are narrow and deep. (e) Eastern boundary currents are shallow and swift.

B. Eastern boundary currents are broad and slow

An eastern boundary current is narrow and swift. (a) True (b) False

B. False

Deep currents are horizontal and rarely move vertically. (a) True (b) False

B. False

Deep ocean water does not travel across the equator. (a) True (b) False

B. False

Surface currents affect about 90% of the world's ocean water (a) True (b) False

B. False

The Gulf Stream moves water away from the equator; the Benguela Current moves some of this same water back toward the equator. (a) True (b) False

B. False

The amount of seawater water flowing in the geostrophic currents of the world ocean is approximately equal to the total amount of water flowing in all the Earth's fresh water rivers. (a) True (b) False

B. False

Movement of ocean currents by gravity and modified by the Coriolis force is called __________. (a) Ekman transport (b) geostrophic flow (c) upwelling (d) downwelling

B. Geostrophic flow

Geostrophic circulation is within a gyre driven by __________. (a) density (b) gravity (c) temperature (d) the Coriolis effect (e) wind

B. Gravity

Benjamin Franklin was the first person to recognize the extent of the ___________ and to publish a navigational chart of it. (a) North Equatorial Current. (b) Gulf Stream. (c) El Niño. (d) Kuroshio Current. (e) Canary Current.

B. Gulf Stream

El Niño results due to an interruption of flow of the __________ Current(s) in the Pacific. (a) Kuroshio (b) Humboldt and Equatorial (c) Canary and North Atlantic (d) West Wind Drift (e) Arctic

B. Humboldt and Equatorial

Deep water circulation in the Pacific Ocean is influenced by __________. (a) extreme cooling and the formation of Pacific Bottom Water (b) hydrothermal vents from the East Pacific Rise (c) sea ice formation and resulting increased salinity of surface water in the south Pacific (d) the size of the Pacific basin (e) the Southern Oscillation

B. Hydrothermal vents from the East Pacific Rise

Which of the following is true of surface water circulation near Antarctica? (a) A gyre is formed here. (b) Two circumpolar currents dominate it, one current that moves water to the east and one current that moves water to the west. (c) It is dominated by water flow directly away from the polar region toward the north. (d) The surface ocean has no strong currents. (e) The polar easterlies drive the circulation of water around the Antarctic continent.

B. Two circumpolar currents dominate it, one current that moves water to the east and one current that moves water to the west.

The immediate source of most of the energy for ocean currents is the ___________. (a) weather (b) wind (c) the sun (d) the tides

B. Wind

As the temperature of water increases, its density ___________. (a) increases (b) decreases

B. decreases

The location where water flow uninterrupted between the Pacific, the Atlantic, and the Indian Oceans is __________. (a) in the Arctic Ocean (b) in the Southern Ocean (c) near Alaska (d) near the equator (e) This does not occur

B. in the Southern Ocean

The arrangement of water masses in the southern Atlantic Ocean from the surface to the bottom is __________. (a) Antarctic Bottom Water, Antarctic Intermediate Water, North Atlantic Deep Water. (b) Antarctic Intermediate Water, Antarctic Bottom Water, North Atlantic Deep Water. (c) Antarctic Intermediate Water, North Atlantic Deep Water, Antarctic Bottom Water. (d) North Atlantic Deep Water, Antarctic Bottom Water, Antarctic Intermediate Water. (e) North Atlantic Deep Water, Antarctic Intermediate Water, Antarctic Bottom Water.

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

Currents tend to move in great ___________ patterns in the northern hemisphere. (a) irregular (b) counterclockwise (c) clockwise (d) random

C. Clockwise

The El Niño weather pattern is associated with __________. (a) about a 0.5 meter difference in sea surface height between Tahiti and Darwin, Australia (b) cold, nutrient-rich water close to the sea surface near the coast of Peru (c) drought and fires in Australia (d) high pressure sitting over coastal Peru (e) trade winds blowing east to west

C. Drought and fires in Australia

The worldwide effect of El Niño includes all of the following except __________. (a) coral reef deaths in the Pacific Ocean (b) crop failure in the Philippines (c) drought in the US Gulf coastal states (d) increased Pacific cyclone activity (e) water shortages in Sri Lanka

C. Drought in the US Gulf coastal states

Currents that result from a balance between pressure gradient and Coriolis effect are termed ___________ currents. (a) Coriolis (b) Density (c) Geostrophic (d) Seismic (e) Internal

C. Geostrophic

Which type of flow works in opposition to Ekman transport in a gyre? (a) counter-current circulation (b) density-driven circulation (c) geostrophic circulation (d) Langmuir circulation (e) thermohaline circulation

C. Geostrophic circulation

The main force driving thermohaline circulation is ___________. (a) wind (b) Coriolis effect (c) gravity (d) electromagnetic attraction

C. Gravity

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

C. Gulf Stream

A system of four currents completing a flow circuit around the periphery of an ocean basin is collectively called a ___________. (a) cell (b) Carroll pattern (c) gyre (d) gimble (e) wabe

C. Gyre

Convection cells driven by the relatively weak winds near the center of gyres are called __________. (a) Ekman transport (b) geostrophic circulation (c) Langmuir circulation (d) thermohaline circulation (e) upwelling

C. Langmuir circulation

Wind moving from the north along the California coast causes water moving along the coast to ___________. (a) move south (b) move toward shore (east) (c) move away from shore (west) (d) move north

C. Move away from the shore (west)

The Sargasso Sea is located in the __________. (a) Arctic Ocean (b) Indian Ocean (c) North Atlantic Ocean (d) North Pacific Ocean (e) South Atlantic Ocean

C. North Atlantic Ocean

Meander loops that pinch off from the main axis of the Gulf Stream are called ___________. (a) oxbows (b) meander scars (c) rings (d) wanderers (e) detached basins

C. Rings

The ultimate source of most of the energy for ocean currents is the ___________. (a) weather (b) wind (c) sun (d) tides

C. Sun

The Ekman spiral is caused by: (a) density differences in the water column. (b) the wind and gravity. (c) the wind and the Coriolis effect. (d) the pycnocline. (e) pressure gradients.

C. The wind and the Coriolis effect.

The only ocean current that continues in an uninterrupted circle around the circumference of the Earth without encountering land is the ___________. (a) Gulf Stream (b) Kuroshio, or Japan, Current (c) West Wind Drift or Antarctic Circumpolar Current (d) Canary Current

C. West Wind Drift or Antarctic Circumpolar Current

Generally the fastest and deepest ocean currents are ___________. (a) northern boundary currents (b) eastern boundary currents (c) western boundary currents (d) southern boundary currents

C. Western boundary currents

During an El Niño event, ___________. (a) the trade winds strengthen (b) the central eastern Pacific ocean becomes cooler (c) sea level falls in the central eastern Pacific ocean (d) a strong equatorial countercurrent develops in the Pacific (e) the Peru Current strengthens

D. A strong equatorial countercurrent develops in the Pacific

Geostrophic flow is a dynamic balance between ___________ and ___________. (a) wind; gravity (b) gyres; continental masses (c) north polar magnetic fields; south polar magnetic fields (d) Coriolis deflection; pressure gradient

D. Coriolis deflection; pressure gradient

The Earth's rotation influences currents by a force (or acceleration, to be correct) known as the ___________. (a) Franklin rotation (b) geostrophism (c) gyral nutation (d) Coriolis effect

D. Coriolis effect

Replacement of water coming from the top to the bottom of the water column is called __________. (a) Ekman transport (b) geostrophic flow (c) upwelling (d) downwelling

D. Downwelling

The first person to comprehend the worldwide pattern of ocean surface currents was probably ___________. (a) Benjamin Franklin (b) Vagn Ekman (c) Fridtjof Nansen (d) Matthew Maury (e) Henry Stommel

D. Matthew Maury

Which ocean surface current carries the greatest volume of water? (a) The Kuroshio (or Japan) Current (b) The North Equatorial Current in the Pacific (c) The South Equatorial Current in the Pacific (d) The West Wind Drift (e) The Canary Current

D. The West Wind Drift

Equatorial currents are driven by the __________. (a) Coriolis force (b) density (c) Ekman transport (d) trade winds (e) westerlies

D. Trade winds

Britain's weather is ___________ than would be expected at that latitude because of the influence of surface currents. (a) colder (b) drier (c) less humid (d) warmer and wetter

D. Warmer and wetter

Strong upwelling occurs in all of the following except __________. (a) between the North and South Equatorial Currents (b) in areas of surface current divergence (c) in the area surrounding the Galapagos Islands (d) where deep ocean water currents are formed (e) where water is constantly pushed away from a coastline

D. Where deep ocean water currents are formed

Most surface currents are driven by the ___________. (a) Earth's rotation (b) Magnetic fields (c) Aurora borealis (d) wind (e) salinity differences of surface waters

D. Wind

Surface ocean circulation is 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

D. Wind; the Coriolis effect and land

Most deep bottom water forms___________. (a) near the ocean floor in the arctic (b) near the ocean floor in the Antarctic (c) near the ocean surface in the arctic (d) near the ocean surface in the Antarctic

D. near the ocean surface in the Antarctic

Deep ocean water generally has high amounts of __________. (a) dissolved organic matter (b) nutrients only (c) oxygen only (d) nutrients and oxygen (e) suspended solids

D. nutrients and oxygen

Countercurrents and undercurrents generally move ___________ than the surface current above, and in __________ direction. (a) faster ... the same (b) faster ... the opposite (c) slower ... the same (d) slower ... the opposite

D. slower ... the opposite

Density of water is a function of its ___________, ___________, and ___________. (a) chemical content; distance from land; turbidity (b) distance from land; depth; rate of flow (c) rate of flow; turbidity; resistance to wind drag (d) temperature; salinity; pressure

D. temperature; salinity; pressure

In the southern hemisphere, the direction of Ekman transport is always: (a) at a 45º angle from the wind direction. (b) perpendicular to the wind direction. (c) to the east of the wind direction. (d) to the left of the wind direction. (e) to the right of the wind direction.

D. to the left of the wind direction

Which of these is generally not an El Niño effect? (a) A rise in the sea level off the coasts of the American Continents. (b) An increase in ocean surface temperature in the eastern Pacific. (c) An increase in rainfall in west coastal countries or states of the American continents. (d) An often catastrophic decrease in the commercial fisheries of the affected countries. (e) A decline in the exotic species of fish and other forms of marine life in the affected waters.

E. A decline in the exotic species of fish and other forms of marine life in the affected waters.

Geostrophic gyres can be described by which of the following statements? (a) They are "turned by the Earth". (b) They depend on Coriolis effect and the position of continental land masses for their direction. (c) They form gyres around the perimeters of ocean basins. (d) They are physically large phenomena. (e) All of the above are true.

E. All of the above are true.

Westward intensification causes __________. (a) a steeper slope of surface water in the western section of the gyre as compare to the eastern section of the gyre (b) equatorial countercurrents (c) the center of the gyre to be shift to the west (d) very swift western boundary currents (e) All of the above statements are the result of westward intensification

E. All of the above statements are the result of westward intensification

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) intensification in subtropical latitudes (d) narrower current (e) All of the above statements are true of western boundary currents

E. All of the above statements are true of western boundary currents

The California Current in the northeastern Pacific Ocean is an example of a __________ current. (a) warm-water, western boundary (b) warm-water, eastern boundary (c) transverse (d) cold-water, western boundary (e) cold-water, eastern boundary

E. Cold-water, eastern boundary

The Canary Current in the northeastern Atlantic Ocean is an example of a __________ current. (a) warm-water, western boundary (b) warm-water, eastern boundary (c) transverse (d) cold-water, western boundary (e) cold-water, eastern boundary

E. Cold-water, eastern boundary

Identify the mismatched pair. (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

E. Labrador Current, Humboldt Current

The unit of measurement used to describe the rate at which a volume of ocean water moves in a current is a(n) __________. (a) calorie (b) ft/s 2 (c) km/h (d) ml/g (e) Sverdrup

E. Sverdrup

Surface waters are pushed away from land and replaced by nutrient-rich bottom water through __________. (a) convergence (b) downwelling (c) land breezes (d) sea breezes (e) upwelling

E. Upwelling

The Ekman spiral is driven by__________. (a) density differences in the water column (b) gravity (c) the Coriolis effect (d) the pycnocline (e) wind

E. Wind

Compared to Antarctic Bottom Water, North Atlantic Deep Water is __________. (a) colder (b) denser (c) higher in nutrients (d) higher in salinity (e) lower in oxygen

E. lower in oxygen

Thermohaline currents tend to flow very ___________. (a) rapidly (b) slowly (c) sporadically

B. Slowly

The densest ocean water is North Atlantic Deep Water. (a) True (b) False

B. False

Thermohaline circulation is wind-driven. (a) True (b) False

B. False

Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Choose the one option that does not fit the pattern. (a) Agulhas Current (b) Benguela Current (c) California Current (d) Canary Current (e) West Australian Current

A. Agulhas Current

Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Choose the one option that does not fit the pattern. (a) California Current (b) Canary Current (c) Gulf Stream (d) North Atlantic Current (e) North Equatorial Current

A. California Current

Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Choose the one option that does not fit the pattern. (a) Gulf of Alaska (b) Indian (c) North Atlantic (d) South Atlantic (e) South Pacific

A. Gulf of Alaska

Which of the following is NOT one of the world's five subtropical gyres? (a) North Atlantic Gyre. (b) North Indian Ocean Gyre. (c) South Pacific Gyre. (d) Nouth Pacific Gyre. (e) South Atlantic Gyre.

B. North Indian Ocean Gyre

Which of the following is NOT one of the main currents with a subtropical gyres: (a) California Current (b) Brazil Current (c) North Equatorial Current (d) Equatorial countercurrent (e) Gulf Stream

D. Equatorial countercurrent

Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Choose the one option that does not fit the pattern. (a) thermohaline circulation (b) density-driven circulation (c) Antarctic Bottom Water (d) Kuroshio Current (e) North Atlantic Deep Water

D. Kuroshio Current

Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Choose the one option that does not fit the pattern. (a) Gulf Stream (b) Kuroshio Current (c) North Equatorial Current (d) Peru Current (e) Somali Current

E. Somali Current

Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Choose the one option that does not fit the pattern. (a) Australian drought (b) decreased fish stock in coastal Peru (c) flooding rains in southeastern U.S. (d) Peruvian upwelling stops (e) strong trade winds

E. Strong trade winds