Chapter 4- atmosphere/ocean circulations
Of the following statements about Ekman spiral and Ekman transport, which is true
Ekman transport is to the right of the wind direction in the Northern Hemisphere
Thermohaline circulation is wind-driven
false
Surface ocean currents
-form large rotating gyres in the major ocean basins -are driven by winds -are influenced by Coriolis effect
To produce a surface current of 1.6 knots in the open ocean, a steady wind of _ knots would be required
80
Which of the following statements is most accurate about tsunami hazards and the number of people at risk
A low tsunami hazard and a high number of people at risk are present along the coast of the eastern United States
Which of the following statements about earthquakes and tsunami hazards is most accurate
A relatively high number of earthquakes and the greatest tsunami hazard occur along the western coast of South America
A. Agulhas current B. Benguela current C. California current D. Canary current E. West Australian current
A. Agulhas current
A. California current B. Canary current C. Gulf Stream D. North Atlantic current E. North Equatorial current
A. California current
The arrangement of water masses in the southern Atlantic Ocean from the surface to the bottom is
Antarctic Intermediate Water, North Atlantic Deep Water, Antarctic Bottom Water
Which body of water is shown with the highest percentage of coastal pollution
Baltic Sea
Of the following currents, which one are parts of the south atlantic subtropical gyre
Benguela current
Which of the following is a western boundary current
Brazil current
A. thermohaline circulation B. density-driven circulation C. antarctic bottom water D. kuroshio current E. north atlantic deep water
D. kuroshio current
A current in the northwestern part of the North Atlantic Subtropical Gyre that transports warm water toward the North Atlantic is called the
Gulf Stream
One of the world's most powerful currents, located off the east coast of the United States, is the
Gulf Stream
Which of the following is not an eastern boundary current
Gulf Stream
Of the following gyres, which one flow in a counterclockwise direction
Indian ocean subtropical gyre
Identify the mismatched pair from the choices below
Labrador Current, Humboldt Current
The Gulf Stream transports warm water into the
North Atlantic
A deep and powerful southward subsurface current the flows under the Gulf Stream in the North Atlantic is the
North Atlantic Deep Water
Of the following surface currents, which one flow from south to north
Peru current
which of the following statements is true of surface ocean currents
Surface currents form the circular patterns in the major ocean basins called "gyres"
An eastern boundary current is generally narrow and swift
false
A doppler flow meter is a scientific instrument used to measure current flow rates
True
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
The thermocline is
a steep temperature gradient int eh ocean that separates deeper cold water from warmer upper water
During a strong El Nino event, the news media might be expected to cover
a tropical cyclone in Hawaii or Tahiti
Warm ocean currents
are warmer than surrounding water
Surface currents affect about 90% of the world's ocean water
false
When a meander from the Gulf Stream pinches off and isolates a body of water within the North Atlantic gyre , the body of water is called a
cod core ring
California Current
cold current, northern hemisphere, temperate latitudes
West Wind Drift
cold current, polar latitudes, southern hemisphere
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 or ring
The coastlines with the greatest tsunami hazard are most commonly associated with what type of plate boundary?
convergent
Downwelling can result from
converging surface currents
Of the following statements about deep ocean currents, which is true
deep ocean currents are important regulators of global climate
The loss of heat from the ocean surface, resulting in lowered temperature, causes ocean water to become
denser
Thermohaline circulation is driven by
density differences
Deep ocean currents are driven primarily by _ and modified by _
density differences; differences in salinity and temperature
The Gulf Stream moves water away from the equator; the Benguela Current moves some of this same water back toward the equator
false
Equatorial currents that are part of the subtropical gyres flow _. Equatorial counter currents between the gyres flow _
east to west; west to west
Which direction do ocean currents in the South Pacific move under El Nino conditions
eastward
Cool ocean currents
generally flow from high latitude towards the equator
Which type of current flow moves in a circular path around a subtropical convergence, reflecting Ekman transport, gravity, and the Coriolis effect
geostrophic circulation
Geostrophic circulation within a gyre driven by
gravity and the Coriolis effect
Deep-Water circulation brings dense, cold, oxygen-rich water from the surface to the deep ocean because of
greater dissolution of oxygen in colder water than warmer water
A large system of rotating ocean currents, usually driven by the major wind belts, is called
gyre
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
What is the overall effect of the stronger than normal trade winds typical of La Nina 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
Upwelling
movement of water from the bottom to the top of the water column
Ekman transport
net water movement to the left or right of the direction of the wind
Thermohaline circulation in the ocean is driven primarily by differences in _ and _ among the masses
temperature; salinity
Gulf Stream
northern hemisphere, temperate latitudes, warm current
The subtropical gyres
play a large role in climate
Deep ocean currents
result from changes in water density (due to temperature and salt content)
Records indicate that the ocean is warming faster in the Arctic polar regions than anywhere else. If that continues possible consequences could be
slowing of deep ocean circulation, resulting in lower oxygen levels in deep water
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
The El Nino souther Oscillation can be best described as
the relationship between sea surface temperature and changing atmospheric pressure
What is the Southern Oscillation
the swapping of high and low pressure zones in the South Pacific under El Nino conditions
Deep ocean water can be enriched in oxygen when it is mixed with surface water
true
Deep ocean water masses have characteristic temperatures and salinities
true
The circular movement of surface water currents driven by the major wind belts are called gyres
true
The five subtropical gyres exhibit geostrophic flow, related to pressure gradients, friction, and the Coriolis effect
true
The main current in Antarctic waters is the Antarctic Circumpolar Current, also called the West Wind Drift
true
Under which conditions are droughts and wildfires common in Australia
under El Nino conditions
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
Why does upwelling occur along the west coast of South America under normal conditions
winds moving westward int eh south pacific drive ocean currents toward the west; deep water rises to replace water driven westward
