ch 6
Of the following statements about Ekman spiral and Ekman transport, which is/are true?
- Ekman transport is to the right of the wind direction in the Northern hemisphere the Northern Hemisphere. - Within the Ekman spiral, deeper water can move in a direction exactly opposite of the wind direction. -Connecting the arrows of water movement from the surface into deeper waters shows the spiral pattern. - The two factors that affect the Ekman spiral are the wind direction and the Coriolis effect. - Because of the Coriolis effect, surface waters move at an angle to the wind direction.
Surface ocean currents ___.
-form large rotating gyres in the major ocean basins -are influenced by Coriolis effect -are driven by winds
Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Please identify the word and/or phrase that does NOT fit the pattern. Enter only the letter of the answer (caps, no period, and not the full entry) in the field below. A. Agulhas Current B. Benguela Current C. California Current D. Canary Current E. West Australian Current
Agulhas current
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.
Examine the five words and/or phrases and determine the relationship among the majority of words/phrases. Please identify the word and/or phrase that does NOT fit the pattern. Enter only the letter of the answer (caps, no period, and not the full entry) in the field below. 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
Strong trade winds
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.
Of the following statements about subtropical gyres, which is/are true? Choose all that apply.
The western boundary current of all subtropical gyres is intensified (it is fast, narrow, and deep). The centers of all subtropical gyres are associated with high atmospheric pressure. Globally, there are five subtropical gyres. There are four main surface currents in each subtropical gyre. The rotation of each subtropical gyre causes a "hill" of water to pile up within it.
The main current in Antarctic waters is the Antarctic Circumpolar Current, also called the West Wind Drift.
True
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
Warm ocean currents ___.
are warmer than the surrounding water
The loss of heat from the ocean surface, resulting in a lowered temperature, causes ocean water to become __________.
denser The cooling of water at the ocean surface causes the temperature to decrease, which, in turn, causes the water molecules to become more compacted (denser) and potentially sink.
Equatorial currents that are part of the subtropical gyres flow ___. Equatorial counter currents between the gyres flow ___ .
east to west; west to east
Which direction do ocean currents in the South Pacific move under El Nino conditions
eastward
Surface ocean currents are vertical currents in the water column that are density-driven.
false
Thermohaline circulation is wind-driven.
false
Cool ocean currents ___.
generally flow from high latitudes towards the equator
The current in the northwestern part of the North Atlantic Subtropical Gyre that transports warm water toward the North Atlantic is called the __________.
gulf stream the Gulf Stream is a western boundary current in the North Atlantic Subtropical Gyre, and transports warm water away from the tropics.
A large system of rotating ocean currents, usually driven by the major wind belts, is called a(n) __________.
gyre An ocean gyre is any large system of rotating ocean currents. In the surface layer of the world ocean, there are five subtropical gyres and several smaller gyres.
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
A deep and powerful southward subsurface current that flows under the Gulf Stream in the North Atlantic is the __________.
north atlantic deep water The North Atlantic Deep Water is a subsurface current that forms as a result of the sinking of cooler, denser water in the North Atlantic.
Match the term or person with the appropriate phrase. Gulf Stream
northern hemisphere, temperate latitudes, warm current
Thermohaline circulation in the ocean is driven primarily by differences in __________ and __________ among water masses.
temp and salinity The term thermohaline (thermo = heat, haline = salt) refers to density differences among water masses mostly influenced by temperature and salinity.
Of the following surface currents, which one(s) flow from south to north?
the Gulf Stream,Peru Current and Kuroshio Current The Gulf Stream flows from south to north along the East Coast of the United States. The Kuroshio Current flows from south to north along Japan.
What is the Southern Oscillation?
the swapping of high and low pressure zones in the South Pacific under El Niño conditions
Western boundary currents such as the Gulf Stream transport warm water from the tropics towards higher latitudes.
true
Under which conditions are droughts and wildfires common in Australia?
under el nino conditions
Surface ocean currents are driven primarily by ________ and modified by ________.
wind; the Coriolis effect and land
The subtropical gyres ___.
play a large role in climate
Deep ocean currents ___.
result from changes in water density (due to temperature and salt content)
