Earth’s Changing Atmosphere CHAPTER NEW CHAPTER Earth’s Changing Atmosphere the BIG idea Earth’s atmosphere is a blanket of gases that supports and protects life. 15.1 Earth’s atmosphere supports life. 15.2 The Sun supplies the atmosphere’s energy. 15.3 Gases in the atmosphere absorb radiation. 15.4 Human activities affect the atmosphere. CHAPTER OUTLINE CHAPTER RESOURCES

Earth’s atmosphere supports life. 15.1 Earth’s atmosphere supports life. The atmosphere is a thin layer surrounding Earth. Gases in the atmosphere provide substances essential for living things. Natural cycles and sudden changes affect the atmosphere. atmosphere altitude density cycle Gases of Earth's Atmosphere click image to enlarge CHAPTER RESOURCES SECTION OUTLINE

The Sun supplies the atmosphere’s energy. 15.2 The Sun supplies the atmosphere’s energy. Energy from the Sun moves through Earth's atmosphere in three ways. radiation conduction Transfer of Energy Radiation, conduction, and convection move energy from place to place. convection CHAPTER RESOURCES SECTION OUTLINE

The Sun supplies the atmosphere’s energy. 15.2 The Sun supplies the atmosphere’s energy. Energy from the Sun moves through Earth's atmosphere in three ways. radiation conduction convection VISUALIZATION See radiation, conduction, and convection in action. CHAPTER RESOURCES SECTION OUTLINE

The Sun supplies the atmosphere’s energy. 15.2 The Sun supplies the atmosphere’s energy. Density and temperature change with altitude. The layers, from top to bottom, are radiation conduction • thermosphere convection • mesosphere • stratosphere • troposphere CHAPTER RESOURCES SECTION OUTLINE

Gases in the atmosphere absorb radiation. 15.3 Gases in the atmosphere absorb radiation. Ozone molecules in the stratosphere absorb harmful ultraviolet radiation. ultraviolet radiation infrared radiation ozone greenhouse effect greenhouse gas CHAPTER RESOURCES SECTION OUTLINE

Gases in the atmosphere absorb radiation. 15.3 Gases in the atmosphere absorb radiation. Greenhouse gases in the troposphere keep Earth warm by absorbing and emitting infrared radiation. ultraviolet radiation infrared radiation ozone greenhouse effect greenhouse gas CHAPTER RESOURCES SECTION OUTLINE

Gases in the atmosphere absorb radiation. 15.3 Gases in the atmosphere absorb radiation. Greenhouse gases in the troposphere keep Earth warm by absorbing and emitting infrared radiation. ultraviolet radiation infrared radiation ozone greenhouse effect greenhouse gas VISUALIZATION See how the greenhouse effect works. CLASSZONE.COM CHAPTER RESOURCES SECTION OUTLINE

Human activities affect the atmosphere. 15.4 Human activities affect the atmosphere. Human activities have added pollutants and ozone-destroying chemicals to the atmosphere. air pollution particulate fossil fuel Natural Sources • dust, pollen, soil, salt • volcanoes and forest fires: gases and particles Human Activities • fossil fuels: gases and particles • unburned fuels: smog • manufacturing: gases and particles • tractors/construction equipment: dust and soil • farming: fertilizers and pesticides smog CHAPTER RESOURCES SECTION OUTLINE

Human activities affect the atmosphere. 15.4 Human activities affect the atmosphere. The amounts of greenhouse gases have been increasing and global temperatures are rising. air pollution particulate fossil fuel smog CHAPTER RESOURCES SECTION OUTLINE

15.1 Earth’s atmosphere supports life. I. Earth’s atmosphere supports life. atmosphere A. The atmosphere makes life on Earth possible. altitude 1. Characteristics of the Atmosphere density 2. Materials in the Atmosphere cycle B. Natural processes modify the atmosphere. 1. Ongoing Processes 2. Sudden Changes CHAPTER RESOURCES KEY CONCEPT SUMMARY

15.2 The Sun supplies the atmosphere’s energy. II. The Sun supplies the atmosphere’s energy. radiation A. Energy from the Sun heats the atmosphere. conduction B. The atmosphere moves energy. convection C. The atmosphere has temperature layers. CHAPTER RESOURCES KEY CONCEPT SUMMARY

15.3 Gases in the atmosphere absorb radiation. III. Gases in the atmosphere absorb radiation. ultraviolet radiation A. Gases can absorb and give off radiation. infrared radiation B. The ozone layer protects life from harmful radiation. ozone greenhouse effect C. The greenhouse effect keeps Earth warm. greenhouse gas CHAPTER RESOURCES KEY CONCEPT SUMMARY

15.4 Human activities affect the atmosphere. IV. Human activities affect the atmosphere. air pollution A. Human activity can cause air pollution. particulate 1. Types of Pollution fossil fuel 2. Effects of Pollution smog 3. Controlling Pollution B. Human activities are increasing greenhouse gases. 1. Sources of Greenhouse Gases 2. Global Warming 3. Reducing Greenhouse Gases CHAPTER RESOURCES C. Human activities produce chemicals that destroy the ozone layer. KEY CONCEPT SUMMARY

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