CK12 Earth Science

Table 15.2: (continued)

Greenhouse Gas Where It Comes From

Methane Decompositionofplantmaterialundersome

conditions, biochemical reactions in stom-

achs

Nitrous oxides Produced by bacteria

Ozone Atmospheric processes

Chlorofluorocarbons Not naturally occurring; made by humans

The greenhouse effect is very important for another reason. If greenhouse gases in the
atmosphere increase, they trap more heat and warm the atmosphere. If greenhouse gases
in the atmosphere decrease, less heat is trapped and the atmosphere cools. The increase or
decrease of greenhouse gases in the atmosphere affect climate and weather the world over.

Lesson Summary

• Allmaterialscontainenergy,whichcanradiatethroughspaceaselectromagneticwaves.
  The wavelengths of energy that come from the Sun include visible light, which appears
  white but can be broken up into many colors.


• Ultraviolet waves are very high energy. The highest energy UV, UVC and some UVB,
  gets filtered out of incoming sunlight by ozone.


• Moresolarenergyreachesthelowlatitudesandtheredistributionofheatbyconvection
  drives the planet’s air currents.

Review Questions

1. What is the difference between temperature and heat?


2. Give a complete description of these three categories of energy relative to each other
   in terms of their wavelengths and energy: infrared, visible light, and ultraviolet.


3. Why do the polar regions have high albedo?


4. Give an example of the saying “energy can’t be created or destroyed.


5. Describe what happens to the temperature of a pot of water and to the state of the
   water as the dial on the stove is changed from no heat to the highest heat.


6. Describe where the Sun is relative to the Earth on summer solstice, autumnal equinox,
   winter solstice and spring equinox. How much sunlight is the North pole getting on
   June 21? How much is the South pole getting on that same day?


7. What is the difference between conduction and convection?


8. What is a planet’s heat budget? Is Earth’s heat budget balanced or not?


9. On a map of average annual temperature, why are the lower latitudes so much warmer
   than the higher latitudes?