1. Convection Currents and the Mantle

2. Convection Currents and the Mantle
Heat Transfer
Heat can transfer in 3 ways
1. Radiation
Transfer of
heat energy by
electromagnetic
radiation
Example: waves on
the EMS scale
2. Conduction
Transfer of heat
By direct
Contact
Example: touching
a metal spoon
In a pot of
Boiling water
3. Convection
Heat transfer
By the movement
Of heated liquids
And gasses
Example: Hot
Air rises

3. Heat Transfer

4. Convection Currents and the Mantle
Changing temperature causes the density to change:
Hot liquid is less dense, moves up to the top
Cool liquid is more dense, moves down to the bottom

5. Convection Currents and the Mantle
Video
The upper mantle is a soft liquid and experiences convection currents
As the fluid close to the core heats, it rises to the top (near the lithosphere) and cools, causing it to cycle back down

6. Convection Currents and the Mantle
Convention currents in the mantle, cause the lithosphere (bottom of the crust) to move
This causes the crust of the earth to move around

7. Draw both pictures below in your notes
Heat
Becomes
cool
Heat
rising
Coolness
sinking
Heat
source