Unit 12 Study GuideThe Earth’s Atmosphere

A. Words to Know

Atmosphere: The air that surrounds our planetAtmospheric pressure: When molecules are more densely packed together closer to Earth’s surface because of the mass of gasses pressing down on themCarbon dioxide (CO₂): This gas is released into the atmosphere by natural and human causesChlorofluorocarbons (CFC’s): Some chemicals that are being blamed for the destruction of the ozone layer Deforestation: Destroying and cutting down of treesExosphere: Merges into our outerspaceGlobal warming: Rise in the average global surface temperaturesGreenhouse effect: Natural heating process of Earth caused by gases trapping heat in the atmosphereGreenhouse gases: The gases that absorb some of the sun’s heat and radiate it back toward EarthIonosphere: Layer in mesosphere where radio waves/radiation can travelNitrogen: This is the most common gas found in Earth’s atmosphereOzone layer: An atmospheric layer of oxygen that protects Earth from the sun’s harmful rays Smog: Caused when pollutants mix with oxygen and chemicalsUltraviolet (UV) radiation: This type of energy comes from the sun and gets absorbed by the ozone layer B. The Composition of Earth’s Air

- Fill in the table using the information in the circle graph.

Water = 0%-4%Other gases = Trace amounts

C. The Layers of the Atmosphere

- Label the 4 main layers of the atmosphere. #4 is closest to the Earth and #1 is farthest away. (pgs. 17-18)

- Be able to answer questions about this graph on the test. To practice, trace your finger along the line and ask yourself “What is the temperature like?” as you go up in altitude through each atmospheric layer.

D. The Greenhouse Effect

Explain how the Sun, atmosphere, and Earth interact in the greenhouse effect to keep us warm. Draw a diagram to help explain your answer. (pg. 21)

E. Also Know…

What causes the atmosphere to be split into different layers? (pg. 17)

Temperature causes the atmosphere to be split into layers (Tropshere: Cooler, Stratosphere: WarmerMesosphere: Cooler, Thermosphere: HOT, Exosphere: Warm

What is the relationship between the greenhouse effect and global warming? (pgs. 3, 21)

The Greenhouse effect traps heat, and in turn the heat warms earth’s surface and causes Earth’s temperature to increase

What are some natural causes of greenhouse gases being cycled through the atmosphere? (pg. 3)

Respiration, Volcanic Eruptions, Water Cycle,

What are some human causes of greenhouse gases being increasingly cycled through the atmosphere? (pg. 3)

Burning Fossil Fuels, Deforestation, Land-use Changes (Burning Coal, Gas, etc Nonrenewable)

What can we do to reduce the amount of CO₂ in the atmosphere? (pg 3)

Use Solar and Wind energy, Reduce amount of renewable energy sources, increase renewable

How do CFC molecules destroy ozone molecules? (You can draw pictures if that helps.)[Pg. 96 in the textbook]