Energy in Earth
Processes
It’s All About Work
Energy
The ability to do work.
 Everything that is done in the universe
involves the use or transfer of energy.
 ***Energy from the sun drives most Earth
surface processes.***

Electromagnetic Energy
Transverse waves radiated by the sun.
 Transverse waves vibrate at right angles to
the direction of movement.
 Most familiar is visible light.
 ***Different types distinguished by
wavelength.***
 See page 14 of ESRT.

Electromagnetic Spectrum
Microwaves
Electromagnetic Spectrum
On the chart – Longer wavelength to the
right, shorter wavelength to the left.
 ***Visible light is the only part that can be
seen with the human eye.***
 ***Heat is given off as infrared
radiation.***

What happens when
electromagnetic energy comes in
contact with a material?
It can be refracted
or bent.
 The direction of
the waves are
changed.


It can be reflected or bounced off.

Transmitted or passed through.

Absorbed or taken into the material.
– Dark colors absorb more than light colors.
– Rough texture absorbs more than smooth.
– ***Thus, dark, rough objects are the best absorbers
of the sun’s energy.***
Energy Transfer
Energy (heat) moves from an area of high
concentration (source) to an area of low
concentration (sink).
 This will continue until the energy
between the source and the sink are even
(dynamic equilibrium).

3 Methods of Transfer

Conduction, convection and radiation
Conduction – transfer of heat energy from atom
to atom or molecule to molecule. Ex. Hot pot
handle.
 Convection – transfer of heat by movement in
fluids, liquids and gasses. Convection currents
transfer heat throughout Earth’s atmosphere,
hydrosphere and mantle. Ex. Smoke rising from
a campfire.
 Radiation – heat transferred via electromagnetic
waves. Can go across empty space. Fastest –
travels at the speed of light.

Heat & Temperature
Temperature – average kinetic energy of
particles in a substance.
 Heat – total kinetic energy of particles in a
substance.
 Heat always flows from higher energy to lower
energy.

Calorie
Different substances heat up at different
rates.
 Unit for measuring heat quantity is the
calorie.
 Defined as the quantity of heat needed to
raise the temperature of 1 gram of water
1 degree Celsius.

Specific Heat
The quantity of heat required to raise the
temperature of 1 gram of a substance 1
degree Celsius.
 Every substance has its own specific heat,
and it is different from all other
substances.
 Liquid water is the highest at 1.0 cal/goC.
 Page 1 ESRT.

In simple terms specific heat is the
resistance of a substance to heating up or
cooling off.
 ***Large bodies of water have a major
moderating effect on weather and climate
because water has the highest specific
heat of any natural substance.***

Heat Energy and Changes of State
Melting – solid to liquid
 Solidification or freezing – liquid to solid
 Evaporation or vaporization – liquid to gas
 Condensation – gas to liquid
 Sublimation – solid to gas

Stored Heat and Changes of State
When a material is in one of the 3 states,
its temperature rises as heat is added to it.
 If the material is in the process of
changing state, its temperature remains
the same.
