Unit 5 - Lesson 4: Surface Currents

Unit 5: Oceanography
Lesson 4: Surface Currents

Current

•A current is a large stream of moving water that flows from one place to another. There are surface currents and deep water currents.

• warm waters move and bring warm weather

Weather & Climate

• helps ships, animals, and other things move around the globe

Movement

Two benefits include:

Surface Currents

Surface currents are movements of water flowing horizontally in the upper part of the ocean’s surface caused by winds. Surface currents affect the climate by moving cold and warm water around the globe.

Gyre

•Gyres are huge circular-moving current systems dominating the surfaces of the oceans bordering one or more continents. Gyres south of the equator move in a counterclockwise direction. Gyres north of the equator move clockwise.

Coriolis Effect

•As Earth rotates-spins on its axis-- the paths of the winds and currents curve. Winds curve to the right—clockwise--in the Northern hemisphere and curve to the left—counterclockwise--in the Southern hemisphere (lower half of the earth). This effect is called the Coriolis effect.

Example of surface current

•The fastest surface current keeps England ice-free in the winter is called the Gulf-Stream.

Multiple Choice

Benefits of currents includes all of the following, except what?

• moves ships around the world

• animals migrate to different parts

• warm weather gets brought to different parts of the world

• creates the seasons: fall, spring, winter, and summer

Multiple Choice

Surface currents affect what?

• the tides

• the climate on continents

• the ocean depth

• the ocean bottom

Multiple Choice

Gyres south of the equator move in what direction?

• direction same as the Southern Hemisphere

• clockwise

• counterclockwise

• depends on the climate

Multiple Choice

The large system of rotating ocean currents is called what?

• eddy or ring

• deep current

• gyre

• wave

Multiple Choice

If the world was not rotating (spinning on its axis) and basically still, then which direction would the wind and currents be going?

• in a straight line

• in a curved path

• clockwise

• counterclockwise