OCE 1001 chapter 7

Which of the following statements is/are true regarding surface ocean currents?

-Gyres in the Southern Hemisphere rotate counterclockwise. -Cold currents flow at high latitudes or from higher latitudes toward the equator.

Of the following statemen ts about subtropical gyres, which is/ are true

-The centers of all subtropical gyres are associated with high atmospheric pressure. -The rotation of each subtropical gyre causes a "hill" of water to pile up within it. -Globally, there are five subtropical gyres. -There are four main surface currents in each subtropical gyre. -The western boundary current of all subtropical gyres is intensified (it is fast, narrow, and deep).

graph

AABW NADW

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

Accidental spills from ocean containers.

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

Antarctic circumpolar

Compared to western boundary currents, eastern boundary currents are:

Broad and slow

Deep ocean currents are driven primarily by ________ .

Density differences

On a west coast in the Northern Hemisphere, what happens to surface waters when winds blow from the south?

Downwelling Waters move on shore

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

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

Humboldt Current

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

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

What is the Walker Circulation Cell?

It is the path that air takes as it moves from high to low pressure, and back to high pressure, in the South Pacific under normal conditions.

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

Kuroshio Current Brazil Current Gulf stream

Deep-water currents move ________ volumes of water and are much ________ than surface currents.

Larger; slower

Lowest density

MIW MADW

In the figure above, which of the following labeled currents is/are part of the South Atlantic Gyre?

N, M

The Gulf Stream transports warm water into the __________.

North atlantic

Why does the west coast of South Africa have high biological productivity?

Nutrients upwelling

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

Somali Current

The deepest and densest water mass in the world ocean is formed in the __________________.

Southern ocean

What would you expect weather to be like on the eastern coast of Australia if the western coast of South America were experiencing unusually warm, wet weather?

The eastern coast of Australia would be experiencing unusually dry weather.

Which of the following is true of surface water circulation near Antarctica?

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

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

Upwellign

On a west coast in the northern hemisphere, what happens to surface waters when winds blow from the north?

Upwelling Waters move off shore

The largest of the great ocean surface currents is the __________.

West Wind Drift

Which of the following currents goes all the way around the world without being interrupted by land?

West wind drift

The observation that one subtropical boundary current is faster, narrower, and deeper than its counterparts is an example of which of the following?

Western intensification

Which factor(s) below drive(s) and shape(s) the pattern of surface ocean currents?

Wind Coriolis effect shape of ocean basins

In the figure above, if this is a westernfacing coast of the northern hemisphere, which wind pattern would cause costal downwelling?

Wind C

In the figure above, of this a western-facing coast of the southern Hemisphere, which wind pattern would cause coastal upwelling?

Wind C

Why does upwelling occur along the west coast of South America under normal conditions?

Winds moving westward in the South Pacific drive ocean currents toward the west; deep water rises to replace water driven westward.

The thermocline is _________________.

a steep temperature gradient in the ocean that separates deeper cold water from warmer upper water

Part complete When a meander from the Gulf Stream pinches off into the warm water south of the current, the eddy is called a __________.

cold core/ eddy ring

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

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

doppler flow meters

Converging surface waters are areas of ________ and ________ productivity.

downwelling; low

Which of the following are western boundary currents?

east austrailia current Kurisho Brazil

Which direction do ocean currents in the South Pacific move under El Niño conditions?

eastward

Ocean frontal systems that spin off from currents such as the Gulf Stream, akin to atmospheric storms, are known as __________.

eddies

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

gravity and the Coriolis effect.

Deep-water circulation brings oxygen from the surface to the deep ocean because of:

greater dissolution of oxygen in colder water than warmer water.

Worlds most powerful current

gulf coast

What is the overall effect of the stronger than normal trade winds typical of La Niña conditions?

lowering of the South Pacific ocean temperature from normal conditions

Fluctuations in the flow of the Gulf Stream current result in curving loops of water known as __________.

meanders

Warm currents flowing ________ on the ________ sides of continents produce warm, humid conditions

poleward; eastern

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

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

subtropical convergence

Sources of deep water in the ocean include all of the following except:

subtropical convergences

In comparison to wind energy, ocean currents can generate more clean, renewable energy because __________.

the density of water is greater than that of air

The El Niño Southern Oscillation can best be described as:

the relationship between sea surface temperature and changing atmospheric pressure.

What is the southern ocilation

the swapping of high and low pressure zones in the South Pacific under El Niño conditions

Cold currents flowing ________ on the ________ sides of continents produce arid conditions.

toward the equator; western

Equatorial currents are driven by the:

trade winds

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

two

Under which conditions are droughts and wildfires common in Australia?

under el nino conditions

Diverging surface waters are areas of ________ and ________ productivity.

upwelling; high

Surface ocean currents are driven primarily by ________ and modified by ________.

wind; the Coriolis effect and land