1. EARTH’S ENERGY

2. Energy from the Sun Nearly all of Earth’s atmosphere energy comes from the sun as electromagnetic waves. Most of the energy comes from the sun reaches Earth in the form of visible light and infrared radiation, and a small amount of ultraviolet radiation.

3. Visible Light Visible light is a mixture of all of the colors that you see: red, orange, yellow, green, blue, and violet. Different colors are a result of different wavelengths. Red and orange have long wavelengths while blue and violet have shorter wavelengths.

4. Infrared Radiation Wavelengths are longer than red light. It is not visible, but it can be felt as heat.

5. Ultraviolet Radiation Wavelengths are shorter than violet light. Can cause sunburns as well as skin cancer and eye damage.

7. Energy in the Atmosphere Most of the energy that keeps Earth warm comes from the sun. Some of the energy is reflected and absorbed in the atmosphere. The rest of the energy reaches Earth’s surface, where it is reflected or absorbed.

9. Energy at Earth’s Surface When Earth’s surface is heated, it radiates some of the energy back into the atmosphere as infrared radiation. The energy from the absorbed radiation heats the gases in the air. These gases form a “blanket” around Earth that holds heat in the atmosphere, which is called the greenhouse effect.

10. Heat Transfer Some energy is transferred from the surface to the atmosphere in the form of heat. Temperature- is the average amount of energy of motion of each molecules of a substance. The energy transferred from a hotter object to a cooler object is referred to as heat. Heat transfers in three ways: radiation, conduction, and convection.

11. Radiation Transfer of energy by electromagnetic waves. You can not actually see the heat but you can feel it through infrared radiation.

12. Conduction The direct transfer of heat from one substance to another substance that it is touching. Ex. Walking on hot sand. Conduction works well in some solids, such as metal, but not as well in liquids and gases. Air and water do not conduct heat very well.

13. Convection The transfer of heat by the movement of fluids. In fluids (gases and liquids), molecules can move from place to place. As the molecules move, they take their heat along with them.

15. Radiation, conduction, and convection work together to heat the troposphere. Air near Earth’s surface is warmed by radiation and conduction of heat from the surface to the air. Convection causes most of the heating of the troposphere