Currents

Currents

6SC.A.3.e: analyze and interpret data to create graphic representations of the causes and effects of waves, currents, and tides in Earth's systems

What are currents?

• Currents are large streams of moving water that flow through the oceans.

• There are two types of currents: surface currents and deep currents.

Surface Currents

• Caused by: Global wind patterns, the shapes of the continents, and the Coriolis Effect.

• Effects: Surface currents directly affect climate by moving warm or cold water around the world, heating or cooling the air above.

Surface Currents: the Coriolis Effect

Deep Currents

• Caused By: Convection, where more dense (colder and more salty) water sinks and less dense, (warmer and less salty) water rises.

• Effects: Deep currents do not affect climate, but they do attract fish by stirring up nutrients that have settled on the ocean floor.

How is heat transferred from Earth’s oceans to land areas?

• Warm Surface Currents

• Example: The Gulf Stream & North Atlantic Drift

What is El Niño?

An abnormal climate event that occurs every 2 to 7 years in the Pacific Ocean, causing changes in winds, currents, and weather patterns that can lead to dramatic climate changes. 

Multiple Choice

Where might you find a gyre?

• Moving in a circle in the South Atlantic Ocean, between South America and Africa

• Moving in a straight line in the North Atlantic from North America to Europe

• Moving in a triangular pattern 500 meters beneath the surface of the South Pacific Ocean

• Moving in one long loop through all of the world's oceans

Multiple Choice

Surface currents are mainly caused by prevailing winds. What is the best synonym for "prevailing?"

• Gentle

• Fierce

• Permanent

• Shifting

Multiple Choice

What effect does the earth's rotation have on surface currents?

• It causes clockwise motion in the northern hemisphere, and counterclockwise in the southern hemisphere.

• It causes counterclockwise motion in the northern hemisphere, and clockwise in the southern hemisphere.

• It causes north-south movement in the northern hemisphere, and south-north movement in the southern hemisphere.

• It causes south-north movement in the northern hemisphere, and north-south movement in the southern hemisphere.

Multiple Choice

What is one effect of the Gulf Stream?

• Winters in Iceland are colder than winters in Georgia.

• Summers in Florida are hotter than summers in

  Sweden.

• Winter days are shorter in England than in New

  Jersey.

• Summers in Spain are hotter than summers in Maine.

Multiple Choice

Hawaii's climate is moderated

by:

• Warm water from the Equator.

• Cold water from the Arctic.

• Cold water from Antarctica.

• Warm water from southern California.

Multiple Choice

What can you infer about the water at the surface of

the ocean, compared to the water hundreds of meters

below?

• Surface water tends to be saltier.

• Surface water tends to be denser.

• Surface water tends to be warmer.

• Surface water tends to be calmer.

Multiple Choice

Which word describes the speed at which the

"global conveyor belt" moves?

• Rapid

• Supersonic

• Gradual

• Variable

Multiple Choice

In the movie, Tim and Moby's raft is probably being

moved by:

• Surface currents

• The global conveyor belt

• The Coriolis Effect

• The Antarctic circumpolar current

Multiple Choice

How does warm water at the surface of the ocean

become colder?

• Icebergs from polar regions melt in it.

• It radiates heat into the atmosphere.

• Snow, hail, and sleet fall into it in polar regions.

• Colder water from below bubbles up and cools it off.

Multiple Choice

What is the relationship between the Gulf Stream

and the global conveyor belt?

• They are unrelated, since the Gulf Stream is a

  surface current and the conveyor belt is a deep-water

  current

• The Gulf Stream is the largest part of the global

  conveyor belt

• The Gulf Stream is the only part of the global

  conveyor belt located in the northern hemisphere

• The Gulf Stream is one segment of the global

  conveyor belt

Multiple Choice

What is the driving force behind surface currents?

• density

• salinity

• wind

• temperature

Multiple Choice

What is the driving force behind deep currents?

• convection

• wind

Multiple Choice

The Coriolis Effect is caused by the ____________ of the Earth.

• shape

• size

• temperature

• rotation

Multiple Choice

Where is ocean water the most dense?

• The surface

• The middle

• The bottom

• Lake Lanier

Multiple Choice

The two types of currents are

• local and global

• sea and land

• surface and deep

• warm and cold

Multiple Choice

Temperature and salinity differences in ocean water cause

• mid-ocean ridges

• deep currents

• surface currents

• high tide and low tide

Multiple Choice

The Gulf stream carries _____________ water from the east coast of The United States to the West coast of Europe.

• cold

• warm

• freezing

• fresh

Multiple Choice

As you go deeper into the ocean, the water is colder and less salty.

• true

• false

Multiple Choice

Due to the Coriolis Effect, water in the northern hemisphere moves

• clockwise

• counter clockwise

• both

• neither

Multiple Choice

Warm ocean currents generally come from

• The North Pole

• The South Pole

• The Equator

• Both A and B

Multiple Choice

A horizontal movement of ocean water that is caused by wind and that occurs at or near the ocean's surface.

• Gulf Stream

• Global Conveyer Belt

• Surface Current

• Gyre

Multiple Choice

What process brings the deep cold ocean currents up to the surface?

• Conduction

• Global Wind Patterns

• Convection Currents

• Temperature and salinity

Multiple Choice

Why are surface currents at the surface of the ocean?

• colder temperature

• colder temperature & more salinity

• warmer temperature & less salinity

• less salinity

Multiple Choice

Ocean water is denser than fresh water at the same temperature due to differences in:

• Wind patterns

• Currents

• Salinity

• Lifeforms