Heating
the Earth
Heat
transfer in the atmosphere
"The sun's energy that is absorbed by the Earth is
spread throughout the
atmosphere in 3 basic ways:
conduction, convection,
and radiation."
Conduction
* The direct transfer of
heat energy from one
substance to
another
* As air above the surface
comes in contact with the
warm ground,
the air is warmed
- temperatures close to
ground are usually
warmest
* soil, water, and air are
poor conductors of heat
- conduction only plays a
minor role in warming
the land,
ocean, and atmosphere
Convection
* The transfer of heat
energy in a fluid- gas or liquid
- Air is a fluid
* Gas/liquid expands when
heated
Density then
decreases
Less
dense material rises causing currents that
transfer heat ; cold air sinks
Radiation
* Transfer of energy, such
as heat, that does not
require
the presence of matter
- energy transferred by wave motion
- can travel through space
* Make up electromagnetic
spectrum
- infrared radiation IR
released by warm/hot objects
- satellites use this to
take heat pictures of the
Earth