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. Air pressure as you move in the atmosphere. Just as air pressure with altitude, so does the density of air. atmosphere altitude density cycle CHAPTER RESOURCES SECTION OUTLINE

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. atmosphere altitude Gases of Earth's Atmosphere density cycle CHAPTER RESOURCES SECTION OUTLINE

Earth’s atmosphere supports life. 15.1 Earth’s atmosphere supports life. Three of the most important cycles that affect the atmosphere are the water cycle, the carbon cycle, and the nitrogen cycle. The Water Cycle Different forms of water (H2O) cycle between Earth's surface and the atmosphere. For example, • Liquid water from oceans and lakes evaporates into gas and enters the atmosphere (plants can also release water vapor from their leaves called transpiration). • Water vapor condenses on small particles in the atmosphere until they become too heavy. • Precipitation atmosphere altitude density cycle CHAPTER RESOURCES SECTION OUTLINE

Earth’s atmosphere supports life. 15.1 Earth’s atmosphere supports life. The Carbon Cycle Carbon dioxide (CO2) and oxygen (O2) gases constantly circulate, or cycle, among plants, animals, and the atmosphere. For example, • Animals inhale air, use some of its oxygen, and exhale air that has less oxygen but more carbon dioxide and water • Plants take in carbon dioxide and release oxygen as they make food in the process of photosynthesis Another photo of the carbon cycle. atmosphere altitude density cycle CHAPTER RESOURCES SECTION OUTLINE

Earth’s atmosphere supports life. 15.1 Earth’s atmosphere supports life. The Nitrogen Cycle Different forms of nitrogen cycle among the atmosphere, the soil, and living organisms. For example, • Tiny organisms remove nitrogen gas (N2) from the air and transform it into other chemicals, which then enter the soil • Plants and animals use solids and liquids that contain nitrogen, which returns to the soil when the organisms die and decay • The soil slowly releases nitrogen back into the air as nitrogen gas atmosphere altitude density cycle CHAPTER RESOURCES SECTION OUTLINE

Earth’s atmosphere supports life. 15.1 Earth’s atmosphere supports life. When sudden events occur, it takes time before the atmosphere is able to restore balance. • Volcanic Eruptions Volcanoes -shoot gases and huge amounts of ash up -gases can produce a haze that may affect the air for many months and lower temperatures worldwide. atmosphere altitude density cycle • Forest Fires - the carbon from trees combines with oxygen making carbon dioxide - wood ash also enters the atmosphere. CHAPTER RESOURCES SECTION OUTLINE

Earth’s atmosphere supports life. 15.1 Earth’s atmosphere supports life. • Dust Storms -Wind, water, or drought can loosen soil. -Powerful windstorms may then raise clouds of this eroded soil adding huge amounts of particles to the air for a time. atmosphere altitude density cycle CHAPTER RESOURCES SECTION OUTLINE

The Sun supplies the atmosphere’s energy. 15.2 The Sun supplies the atmosphere’s energy. The Sun supplies the atmosphere's energy. radiation 70% = 50% absorbed by the Earth’s surface + 20% absorbed by clouds and the atmosphere conduction 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.visualization example radiation conduction Transfer of Energy Radiation, conduction, and convection move energy from place to place. convection CHAPTER RESOURCES SECTION OUTLINE

15.2 radiation conduction convection 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: The last layer before outer space. temperature increases as you rise. convection • mesosphere: air is thin (less than 0.1%) most meteors burn up here temperature decreases as you rise You can use the word parts to help you recall the temperature layers. tropo–"turning" strato–"spreading out" meso–"middle" thermo–"heat" • stratosphere: clear, dry layer ozone temperature increases as you rise • troposphere a: contains about 80% of the total mass of the atmosphere almost all of the water vapor temperature decreases as you rise Vocab flip cards: http://www.classzone.com/books/ml_science_share/con_review_06/launchCR_06.htm CHAPTER RESOURCES SECTION OUTLINE

Gases in the atmosphere absorb radiation. 15.3 Gases in the atmosphere absorb radiation. Gases can absorb and give off radiation. ultraviolet radiation -The atmosphere can affect light in four ways. 1. It can absorb light 2. reflect it 3. let it pass through 4. Air can also emit, or give off, light infrared radiation ozone greenhouse effect greenhouse gas Although air does not emit much visible light, certain gases absorb and emit radiation that is similar to visible light. CHAPTER RESOURCES SECTION OUTLINE

Gases in the atmosphere absorb radiation. 15.3 Gases in the atmosphere absorb radiation. The ozone layer protects life from harmful radiation when the 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. 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 different types of pollution 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. Human activities put chlorine and other ozone-destroying chemicals in the stratosphere that break down our ozone. air pollution particulate fossil fuel 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

Human activities affect the atmosphere. 15.4 Human activities affect the atmosphere. What is global warming? Do you believe it is happening? How can we make a difference? 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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