1. Convection Currents and the Mantle
Heat Transfer
Convection Currents and the Mantle

2. Heat Transfer
Earth’s molten outer core is nearly as hot as the surface of the sun.
Heat is transferred from the core to the surface of the Earth through liquids and solids.

3. Heat Transfer
Heat Transfer – is the movement of energy from a warmer object to a cooler object.
What heat transfer?

4. There are three types of heat transfer:
What are the types of heat transfer?
There are three types of heat transfer:
Radiation
Conduction
Convection

5. Radiation: is the transfer of energy through empty space.
What is radiation?
Radiation: is the transfer of energy through empty space.

6. Radiation
Example:
Sunlight is radiation that warms the Earth’s surface
Heat you feel from around an open flame or fire
Radiation

7. Conduction: is heat transfer by direct contact of particles of matter.
What is conduction?
Conduction: is heat transfer by direct contact of particles of matter.

8. Conduction
Example:
Heat is transferred from the hot soup and the pot to the particles that make up the spoon.
Heat transferred to the particles of the spoon from the pot and hot water

9. Convection What is convection?
Convection: is heat transfer by the movement of a heated fluid
During convection heated particles of fluid begin to flow. Transferring heat energy from one part of the fluid to another.

10. What causes convection?
Heat transfer by convection is caused by differences of temperature and density within a fluid.
Density - Is a measure of how much mass there is in a volume of a substance.
What is density?

11. Convection Current
A constant flow begins as the cooler fluid continually sinks to the bottom of the pot and the warmer fluid rises.
Convection Current – is the flow that transfers heat within a fluid
What is a convection current?

12. Convection

13. Convection Current
What sets convection currents in motion?
The heating and cooling of the fluid, changes in the fluid’s density and the force of gravity combine to set convection currents in motion.

14. Convection and the Earth’s Mantle
Earth’s mantle responds to heat.
Convection currents flow in the Asthenosphere.
The heat source for these currents come from the Earth’s core and from the mantle itself.
Where does the heat source for the Earth’s currents come from?

15. Convection and the Earth’s Mantle

16. Convection and the Earth’s Mantle