Chapter 7 Oceanography
Deep ocean currents often move cold, dense water away from the poles.
True
downwelling
movement of water from the top to the bottom of the water column
An indirect method of measuring ocean current is the use of
radar altimeters
The Ekman spiral is caused by:
the wind and the Coriolis effect.
Surface ocean currents are driven primarily by ________ and modified by ________.
wind; the Coriolis effect and land
geostrophic current
water flow driven by gravity and modified by the Coriolis force
The densest ocean water is North Atlantic Deep Water.
False
Compared to western boundary currents, eastern boundary currents are:
broad and slow.
Of the following statements about subtropical gyres, which is/are true
1. Globally, there are five subtropical gyres. 2. The rotation of each subtropical gyre causes a "hill" of water to pile up within it. 3. The western boundary current of all subtropical gyres is intensified (it is fast, narrow, and deep). 4. There are four main surface currents in each subtropical gyre. 5. The centers of all subtropical gyres are associated with high atmospheric pressure.
Of the following conditions, which is/are related to strong El Niño events?
1. Increased abundance of hurricanes in the eastern Pacific Ocean 2. Higher sea levels in the eastern Pacific Ocean associated with warmer water 3. Increase in sea surface temperatures and destruction of coral reefs in the eastern Pacific Ocean
The West Wind Drift (Antarctic Circumpolar Current) is a part of which of the following subtropical gyres?
1. Indian Ocean Subtropical Gyre 2. South Atlantic Subtropical Gyre 3. South Pacific Subtropical Gyre
Of the following locations, where would upwelling be expected to occur?
1. Where there is a shallowly submerged sea floor obstruction, such as a table mount 2. In areas of diverging surface currents, such as along the equator 3. Where there is a sharp bend in a coastline 4. In areas of offshore winds
Western intensification causes:
1. equatorial countercurrents. 2. a steeper slope of surface water in the western section of the gyre as compare to the eastern section of the gyre. 3. very swift western boundary currents. 4. the center of the gyre to be shift to the west. 5.All of the above statements are the result of westward intensification.
Of the following surface currents, which one(s) flow generally from west to east?
1.Equatorial Counter Current 2. West Wind Drift 3. North Pacific Current
The actual movement of surface water due to Ekman transport in the Northern Hemisphere is about __________.
45° to the right of wind direction
Deep ocean water does not travel across the equator.
False
Surface ocean currents are vertical currents in the water column that are density-driven.
False
Surface or wind-driven currents move water primarily in a vertical direction in the ocean.
False
The West Wind Drift occurs at 60°N around the Arctic Circle.
False
Indian Ocean currents that are generated by seasonal changes in weather patterns are the __________ and __________ Currents.
Somali/Southwest Monsoon
Downwelling may be the result of winds blowing parallel to a coastline or the convergence of surface currents.
True
Dynamic topography can be used to determine current direction and velocity.
True
In the northern hemisphere, Ekman transport pushes surface water to the right of the wind direction.
True
Monsoons are seasonal pressure systems that develop at lower latitudes over continents, which cause changes in seasonal winds and precipitation patterns.
True
Western boundary currents such as the Gulf Stream transport warm water from the tropics towards higher latitudes
True
The largest of the great ocean surface currents is the __________.
West Wind Drift
Canary Current
cold current, northern hemisphere, temperate latitudes
Benguela Current
cold current, southern hemisphere, temperate latitudes
The worldwide effects of El Niño include all of the following except:
drought in the U.S. Gulf coastal states.
During winter months, monsoon winds over the Indian Ocean:
flow from land to sea and are dry.
Compared to Antarctic Bottom Water, North Atlantic Deep Water is:
lower in oxygen.
Kuroshio Current
northern hemisphere, temperate latitudes, warm current
Sources of deep water in the ocean include all of the following except:
subtropical convergences
All are true of the Antarctic Circumpolar Current except:
the Antarctic Circumpolar Current contributes to the development of Antarctic bottom water in the WEDDELL Sea.
Deep ocean current movement is also known as __________.
thermohaline flow
In the southern hemisphere, the direction of Ekman transport is always:
to the left of the wind direction.
Equatorial currents are driven by the:
trade winds.
Compared to an eastern boundary current in a gyre, which of the following statements is true for a western boundary current?
warmer water narrower current deeper current increased current velocity All of the above statements are true of western boundary currents.
Strong upwelling occurs in all of the following except:
where deep ocean water currents are formed.
