M008785 Map of ocean gyres

M008785 Map of ocean gyres

Description

This is a colour map showing the Earth's main ocean gyres - mounded circular currents - and the Antarctic circumpolar current. Segments of each gyre are colour-coded to show cold and warm currents.

Acknowledgements: Copyright Education Services Australia Ltd.

Educational value
Mounds of circulating water in the Pacific, Indian and Atlantic oceans are known as 'subtropical gyres'. Ocean currents circulate around the gyres, clockwise in the Northern Hemisphere and anticlockwise in the Southern Hemisphere. The ocean surface at the centres of these gyres is up to a metre above mean sea level.
Ocean surface current systems are driven by winds. Friction between wind and the water surface sets the upper layer of ocean into motion. The subtropical gyres are driven mainly by easterly trade winds near the equator and westerly winds at higher latitudes.
Warm boundary currents, such as the East Australian current, flow polewards on the western boundaries of the major oceans. These currents are among the fastest and deepest of the ocean currents, and distribute heat to the polar regions. The cool currents flowing towards the equator on the eastern sides of the oceans are wider, shallower and slow moving.
The cold Antarctic circumpolar current, driven by westerly winds, circles Antarctica. This current extends deeply, carrying more water than any of the other currents, and is the only current to flow around the globe. It has an important role in distributing water and heat between the Indian, Pacific and Atlantic oceans.
Year level
5; 6; 7; 8; 9
Topics
Ocean currents
Antarctica
Learning area
Geography
Science
Strand
Geography/Science
Rights
© Education Services Australia Ltd 2011 (except where otherwise indicated). You may copy, communicate and adapt this metadata for non-commercial educational purposes provided you retain all acknowledgements associated with the material.