1. CH. 15-2
Energy Transfer in
the Atmosphere

2. Energy from the Sun
 The Sun provides most of the
energy on Earth.
 Three things happen when
Earth receives the energy:
 Some is reflected back into
space by clouds, atmospheric
particles, & Earth’s surface.

3. Energy from the Sun
 Some energy is absorbed
by the atmosphere
 The rest is absorbed by
land and water on Earth’s
surface.

4. Energy from the Sun
 About 35% is reflected
back into space.
 6% by the atmosphere
 4% by Earth’s surface
 25% by clouds

5. Energy from the Sun
 The other 65% is absorbed.
 15% by the atmosphere
 50% directly or indirectly
by Earth’s surface

6. Heat
 Heat energy flows from
warm to cold.
 Heat energy is absorbed by
roads, rocks, water, & soil.
 Heat is transferred through
the atmosphere in 3 ways:

7. Heat
 Radiation
 Conduction
 Convection

8. Radiation
 Radiation – Energy from
the sun transferred in the
form of waves or rays.
 You feel the radiation when
the Sun warms your face or
skin.

9. Conduction
 Conduction – the transfer
of energy that occurs when
molecules bump into one
another.
 In other words, one object
comes into contact with
another….

11. Conduction
 Energy will travel from the
warmer object to the cooler
object.
 Earth’s surface conducts
energy to the atmosphere
by air moving over warm
land.

12. Convection
 Convection – is the
transfer of heat by the flow
of material.
 Convection circulates heat
throughout the
atmosphere. How?

13. Convection
 As air is warmed it
becomes less dense &
rises.
 Cooler air moves in to
replace the warm air.

15. Water Cycle
 Hydrosphere – all the water
on Earth’s surface.
 Evaporation – when water
changes from a liquid to gas.
 Condensation – when water
changes from a gas to a
liquid.

16. Water Cycle
 Water evaporates from
oceans, lakes & streams AND
transpiration from plants
 The water vapor (gas)
condensates forming clouds.
 The water in clouds falls to
Earth as precipitation