Class Notes (1,200,000)
CA (650,000)
UTSG (50,000)
Geography (500)
GGR100H1 (100)

Earth's energy balance

Course Code
Joseph Leydon

This preview shows half of the first page. to view the full 2 pages of the document.
Geography Lecture #3
January 18, 2011
Earths Energy Balance
the sun emits radiation in a spectrum- UV, infared, etc
different gasses absorb different types of radiation
clouds have the property of reflecting radiation to space- wave hits the
cloud and bounces back up to space, doesnt change wavelength, just
reflects back
white surfaces reflect whereas dark or black surfaces absorb
radiation can get scattered by particles and clouds that bend them
therefore a smaller amount of radiation makes it to the surface
the solar constant is the amount of solar radiation we receive at the top
of the atmosphere
Fate of incoming solar radiation (short wave)
scattering: gas molecules and dust change direction of radiation
without altering wavelength-> diffuse radiation
which is why a cloudy day still allows daylight to be seen
reflection: bounce back to space
we reflect 31% of the radiation [known as Albedo]
absorption: assimilation of radiation by molecules of matter, converted
into other forms of energy
earth is pretty bright in space because we are reflecting 31%
the moon reflects 6%
tiny droplets that reflect radiation
they are small particles that exist in the atompshere
we produce a lot of aerosols in our industrial activities
Overall energy balance
in the long run, incoming radiation= outgoing radiation
Heat transfer at the Earths surface
45% of incoming solar radiation reaches the Earths surface
You're Reading a Preview

Unlock to view full version