Ch 7 hw ??

Which of the following are western boundary currents?

-East Australia Current -Kuroshio Current -Brazil Current

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

-Surface waters move offshore. -Upwelling occurs.

Which current below would be expected to have a width on the order of 300 kilometers (186.4 miles) and a speed on the order of 17 kilometers (10.6 miles) per day?

Benguela Current

Why do the lengths of the arrows in the Ekman spiral get shorter and shorter as you move deeper into the water column?

Deeper water moves at a slower speed due to friction.

Why is Antarctic Bottom Water so dense?

It is cold and salty.

What common household item is used in this video to demonstrate the Ekman spiral?

a deck of playing cards

Which ocean current is the strongest and fastest ocean current in the world?

the gulf stream

Palm trees associated with the subtropics can be found at the northern tip of the British Isles in Scotland. This is due to the transfer of heat from _________________

the north atlantic current

What is the Southern Oscillation?

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

What factor(s) drive(s) Ekman transport?

the wind and the Coriolis effect.

____________ is caused by density changes near the poles and equator.

thermohaline circulation

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.

Surface ocean currents ___.

-are influenced by Coriolis effect -are driven by winds -form large rotating gyres in the major ocean basins

Which force(s) drive(s) water circulation in the deep ocean?

-differences in water density -differences in water salinity -differences in water temperature

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

-downwelling occurs -Surface waters move onshore.

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

-lots of coastal upwelling -high concentrations of nutrients in the surface water

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

-shape of the ocean basins -Coriolis effect -winds

In which direction does the surface current move in relation to the wind in the Southern Hemisphere?

45 degrees to the left

Why are western boundary currents intensified compared to eastern boundary currents?

Earth rotates from west to east, pushing water more strongly toward the west.

Which current that flows along the equator is driven by a difference in sea level caused by ocean circulation patterns?

Equatorial Countercurrent in the Pacific Ocean

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 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.

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

To what depth in the ocean does the Ekman spiral extend?

about 100 meters (330 feet)

Waters along the California coast are colder than those along the mid-Atlantic shore of the U.S. because ___________ occurs as surface waters move away from the coast.

costal upwelling

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

eastward

Freezing seawater at _________ leads to increases in salinity and density.

high latitudes

Which process causes downwelling off the coast of Antarctica?

ice formation

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

In the Northern Hemisphere, the Ekman spiral moves layers of water to the _____ of the wind direction and Ekman transport (the overall direction of water movement) is to the _____.

right; right

Under which conditions are droughts and wildfires common in Australia?

under El Niño conditions

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

west wind drift