Printed on 3/25/2015

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Lesson 301:

THE ATMOSPHERE A lesson covering the structure, composition, and properties of the Earth's atmosphere.

Fundamental Questions Attempting to give thorough and reasonable answers to the following questions will help you gauge your level of understanding this lesson. Students that can confidently answer these questions have mastered the concepts of this lesson.

1. Which layer of the atmosphere is most like the troposphere?

2. At what altitude does outer space begin? 3. What is the most important gas in our atmosphere? 4. Which is more important: the nitrogen cycle, the carbon

cycle, or the water cycle? 5. Will global warming increase or decrease the total

amount of water vapor in the atmosphere?

6. Why is mountain climbing in the Himalayas so dangerous?

7. Do hamburgers cause global warming? 8. How is the atmosphere similar to the interior of the

Earth? 9. Would air from the thermosphere feel hot or cold? 10. In what ways does the Greenhouse Effect help life to

survive?

Lesson Objectives At the end of this lesson, students should have mastered the objectives listed below.

1. List the components of the atmosphere and their relative percentages. 2. Compare and contrast the various layers of the atmosphere. 3. Describe the chemical components of air and explain the properties and importance of each component. 4. Understand that the composition and structure of the atmosphere varies with location and season. 5. Describe the relationship between temperature and altitude and explain why some layers of the atmosphere have a

temperature inversion. 6. Describe the basic steps of the nitrogen and carbon cycles and explain why they are important to life. 7. Describe the Greenhouse Effect. 8. Explain what the importance of ozone is to our atmosphere and describe what has happened to the ozone layer. 9. Understand that aerosols are responsible for vibrant sunrises/sunsets and help lower the atmosphere's temperature. 10. Appreciate the dangers of mountain climbing as they relate to the atmosphere. 11. Distinguish between the words weather and climate. 12. Understand the role fossil fuels play in escalating global warming. 13. Outline the stages in the formation of our atmosphere. 14. Describe the factors and components that lead to aurorae. 15. Describe the relationship between air pressure and altitude. 16. Draw a scaled model of the Earth that displays the relative thickness of the atmosphere.

Important Terms The following terms are some of the vocabulary that students should be familiar with in order to fully master this lesson.

1. aerosols 2. air 3. air pressure 4. ammonia 5. atmosphere 6. aurora australis 7. aurora borealis 8. aurorae 9. blue-green algae 10. carbon dioxide 11. catalyst 12. chlorofluorocarbons 13. climate

14. diatomic 15. environmental lapse rate 16. exosphere 17. Greenhouse Effect 18. greenhouse gas 19. inert gas 20. ionosphere 21. jet stream 22. mesopause 23. mesosphere 24. methane 25. monatomic 26. Mount Everest

27. nitrogen cycle 28. normal lapse rate 29. oxygen 30. ozone 31. stratopause 32. stratosphere 33. temperature inversion 34. thermosphere 35. tropopause 36. troposphere 37. ultraviolet radiation 38. water vapor 39. weather

Assessment Questions The following are examples of questions that students should be able to answer. These or similar questions are likely to appear on the exam.

1. What are the components of air in order of abundance?

2. Draw a pie chart of the components of air, labeling the percentage of each component.

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3. What is the most abundant gas in the atmosphere?

4. Describe the basic steps of the Nitrogen Cycle. 5. If humans inhale oxygen and exhale carbon

dioxide, how does mouth-to-mouth resuscitation work to jump start a person's respiration?

6. What are the differences between the oxygen we breathe and pure oxygen?

7. What role does Argon play in our atmosphere? 8. How much of the atmosphere consists of water

vapor? 9. List 5 ways that life on Earth benefits from trees? 10. Describe the basic steps of the Carbon Cycle. 11. Describe the Greenhouse Effect. 12. Where in the atmosphere is the ozone layer

located and why is it important to life on Earth? 13. Why is hydrogen mainly found in the upper

reaches of the atmosphere? 14. What is the thickest layer of the atmosphere? 15. In what layer of the atmosphere do satellites orbit

the Earth? 16. Why do temperatures in the thermosphere and

stratosphere increase with elevation? 17. Compare and contrast weather and climate. 18. Why is the amount of carbon dioxide in our

atmosphere increasing?

19. Why are water vapor and dust important constituents of our atmosphere?

20. List the names of the atmospheric layers and their boundaries in order from lowest to highest.

21. Why are temperatures in the thermosphere incomparable to temperatures in the troposphere?

22. What causes auroral displays? 23. If the temperature at sea level were 23°C, what

would the air temperature be at a height of 2 kilometers under average conditions?

24. What is the approximate height and temperature of the stratopause?

25. At what altitude is the temperature of the atmosphere lowest and what is that temperature?

26. Where in the atmosphere is air pressure greatest?

27. What planet, besides Earth, is experiencing a runaway greenhouse effect?

28. On a spring day, Stoneham had a surface temperature of 10°C and a nearly constant environmental lapse rate of 6.5°C per kilometer. The temperature at the tropopause is -55°C. What is the height of the tropopause?

29. Draw a scaled model of the Earth that displays the relative thickness of the atmosphere. The radius of the Earth is 6378 kilometers.

Related Web Sites The following are some web sites that are related to this lesson. You are encouraged to check out these sites to obtain additional information.

1. http://www.windows2universe.org/earth/Atmosphere/overview.html 2. http://en.wikipedia.org/wiki/Atmosphere_of_Earth 3. http://www.ouramazingplanet.com/142-earth-atmosphere-layers-atmospheric-pressure-infographic.html 4. http://en.wikipedia.org/wiki/Mount_Everest 5. http://adventure.nationalgeographic.com/adventure/everest/

Related Book Pages The following are the pages from your book that correspond to this lesson.

Comprehensive E.S. Book Intensive/Honors E.S. Book Meteorology/GIS Book pp. 476-480 pp. 270-274 pp. 39-52

Massachusetts Standards The following are the Massachusetts Framework Standards that correspond to this lesson.

Earth Science Learning Standard(s) 2.2, 3.2, 3.3

What’s Next?

Notes

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The Atmosphere A. Atmosphere – the envelope of gases that surrounds a planet; the air we breathe;

protects us from energy and particles from the Sun; insulates us at night; interacts with the surface and space to produce weather. 1. Weather – the state of the atmosphere at a given time and place 2. Climate – a description of aggregate weather conditions; the sum of all statistical

weather information that helps describe the long-term pattern of weather in a location

B. Composition of Earth’s Atmosphere in Past 1. volcanic eruptions and possibly comet impacts likely produced atmosphere 2. originally consisted of mainly ammonia and methane (both deadly poisonous

gases) with some water vapor 3. Sunlight caused chemical reactions that changed composition of air, forming

carbon dioxide (CO2), nitrogen (N), and ozone (O3) a. without ozone “umbrella” shielding Earth’s surface from Sun’s ultraviolet

light, most life could not exist 4. diatomic oxygen (O2) was produced by blue-green algae and later by plants

a. At first, oxygen combined with iron to produce iron oxide (rust), but later the oxygen accumulated substantial quantities in the atmosphere

b. O2 and CO2 levels relatively stable as of 600 million years ago c. Pure oxygen (monatomic O) is rare in the lower atmosphere and is

flammable. C. Composition of Earth’s Atmosphere Now

1. The air you breathe is Earth’s most important natural resource 2. 78% nitrogen, 21% oxygen, 0.93% argon (an inert gas), 0.036% CO2, 0-4% water

vapor, 0.17% trace gases (neon, helium, krypton, xenon, methane, hydrogen, ozone)

a. the nitrogen cycle – bacteria in soil combine with nitrogen in air to form nitrates; plants use nitrates to produce proteins; proteins then used by living things to grow and repair body parts; when living things die and decay the nitrogen is returned to the air to be used again

b. CO2 (a greenhouse gas ) helps trap heat close to Earth’s surface, which is called the Greenhouse Effect . Plants use CO2 during photosynthesis and release oxygen into the air as a result. Respiration of animals and other life return CO2 to air, so CO2 levels used to remain fairly balanced. This process of recycling CO2 is called the carbon cycle .

• Today, burning of fossil fuels (gasoline, coal, etc.) is increasing the levels of CO2 at an alarming rate, causing an imbalance in the carbon cycle and global warming.

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c. Water vapor • Plays key role in warming of the atmosphere and influencing

weather. Water is also a greenhouse gas. • Amount of water vapor in air varies for place and season.

d. Aerosols - solid and liquid particles suspended in air; consist of dust, sea salt, smoke, volcanic ash, microorganisms, and other small particles; cause red and orange skies during sunsets/sunrises

• Provide a surface on which water vapor can condense • Can absorb or reflect incoming solar radiation which can lower

Earth’s temperature • Help scatter sunlight to create vibrant sunrises/sunsets

e. Ozone – a form of oxygen that is made up of three oxygen atoms chemically bonded together (O3)

• Not the same as the oxygen we breathe • Smells pungent • Very small amount in the atmosphere • Distributed unevenly • Concentrated in the stratosphere, between 6 and 31 miles up • Requires a single atom of oxygen (O) to combine with diatomic

oxygen (O2) in the presence of a catalyst. This happens more easily in the stratosphere because ultraviolet light from the sun creates single atoms of oxygen

• Ozone protects us from the sun’s ultraviolet (UV) radiation • Holes have opened up in the ozone layer due to the chemical

reactions between ozone and chlorofluorocarbons (CFC’s). CFC’s are a manmade chemical that are now mostly outlawed. The largest ozone hole is found over Antarctica because ice crystals in the atmosphere there helped the CFC’s to deplete the ozone

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D. Structure of the Atmosphere

1. Atmosphere held close to Earth by gravity a. Air pressure – downward push of atmosphere due to gravity pulling air

toward Earth’s surface b. 99% of atmosphere’s mass is below an altitude of 32 kilometers (19

miles) • Half of the atmosphere lies below an altitude of 5.6 kilometers (3.5

miles) • At an altitude of 100 Km (62 miles), the air is so thin that the density

is less than that found in an artificial vacuum at the surface of Earth • There is no precise boundary for the end of the atmosphere.

Spacecraft which orbit Earth are technically still in the atmosphere. c. Air pressure greatest at surface due to pressure from overlying layers of

atmosphere • At sea level, the weight of a column of air would be 14.7 pounds per

square inch 2. Atmosphere divided into layers according to major changes in its temperature

a. Troposphere • lowest layer of atmosphere; touches surface where we live • most weather occurs here • height varies between about 17 Km at equator and about 7 Km at

poles • Temperature decreases with increasing altitude because of lower air

density and this is called the environmental lapse rate. Temperature drops about 6.5°C for every Km above su rface, which is called the normal lapse rate . However, the environmental lapse rate varies by season and location so the normal lapse rate is not always present

• Some locations experience a temperature inversion , which means that temperatures increase with height rather than decrease

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• tropopause – area where air temperatures remain fairly constant; boundary between troposphere and stratosphere

b. Stratosphere • extends from tropopause to about 50 Km • Air temp. in lower stratosphere is constantly very cold (–60°C) • Jet stream – very strong winds that blow horizontally eastward in

lower stratosphere around Earth • Ozone (O3) present between 16 and 60 Km above sea level; ozone

absorbs harmful UV light causing temp. increase with altitude increase

• Stratopause – zone in stratosphere where temp. is highest; boundary between stratosphere and mesosphere

c. Mesosphere • Extends from about 50 Km to 80 Km • Temp. decreases with increasing altitude • Coldest region of atmosphere (temp. drops to –90°C ) • Mesopause – boundary of the mesosphere

d. Thermosphere • Extends from 80 Km into space • N2, O2, and O absorb UV light and temps. Reach as high as 2000°C • Very few gas particles present (a lot of space between particles) so

air does not “feel” hot • Ionosphere – lower thermosphere; extends from 80 Km to 550 Km;

gases change to ions (electrically charged atoms) by absorbing UV light and X-rays; important for reflecting radio wave transmissions, but ionic storms can also disrupt communications; energized gases called aurorae occur in this layer

• Exosphere – upper thermosphere extends thousands of Km’s into space; satellites orbit Earth here; very thin air

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The Fix

This has been the warmest winter on record,except in the most politically important partof the world

By By Philip BumpPhilip Bump March 19March 19

This map, showing deviation from normal temperatures by part of the world in February, is stunning. And for advocates ofThis map, showing deviation from normal temperatures by part of the world in February, is stunning. And for advocates of

taking strong action on climate change, probably a little depressing.taking strong action on climate change, probably a little depressing.

When the National Oceanic and Atmospheric Administration announced that When the National Oceanic and Atmospheric Administration announced that 2014 was the warmest year on record2014 was the warmest year on record, we, we

couldn't help but notice that the Eastern United States was among the places that recorded their coldest temperatures lastcouldn't help but notice that the Eastern United States was among the places that recorded their coldest temperatures last

year. The year-end map was the minor league version of the map above, which shows a giant blue blanket over half of theyear. The year-end map was the minor league version of the map above, which shows a giant blue blanket over half of the

country -- despite this being the warmest winter on record.country -- despite this being the warmest winter on record.

That eastern half, of course, is where most of America's residents live and all of its federal legislators work. Which is why weThat eastern half, of course, is where most of America's residents live and all of its federal legislators work. Which is why we

get things like Sen. Jim Inhofe (R-Okla.) get things like Sen. Jim Inhofe (R-Okla.) bringing a snowballbringing a snowball to the Senate floor for show-and-tell. Inhofe was right in one to the Senate floor for show-and-tell. Inhofe was right in one

sense: February did end up being colder than usual. And for those who insist that cold weather disproves the idea of asense: February did end up being colder than usual. And for those who insist that cold weather disproves the idea of a

warming climate (which warming climate (which it obviously doesn'tit obviously doesn't), that was just more fodder.), that was just more fodder.

The most powerful parts of the world were, on the whole, significantly less warm during the record-setting February.The most powerful parts of the world were, on the whole, significantly less warm during the record-setting February.

Compare the map at the top of the page with the ones below, contrasting population (using data from Compare the map at the top of the page with the ones below, contrasting population (using data from NASANASA) and, to) and, to

measure relative power, economics (from measure relative power, economics (from the World Fact Bookthe World Fact Book) across the planet. Western Europe and the Eastern United) across the planet. Western Europe and the Eastern United

States were colder than many places -- and disproportionately economically powerful.States were colder than many places -- and disproportionately economically powerful.

PopulationWealth times population

Quick explanation: The darker the color, the higher the value relative to the rest of the world. "Wealth times population"Quick explanation: The darker the color, the higher the value relative to the rest of the world. "Wealth times population"

is simply the average income in each location (based on country) times the population in that location. Each map isis simply the average income in each location (based on country) times the population in that location. Each map is

broken down into one-degree latitude/longitude blocks. View large versions: broken down into one-degree latitude/longitude blocks. View large versions: populationpopulation; ; incomeincome..

And it's economics that often motivates opposition to taking action on climate change, as we And it's economics that often motivates opposition to taking action on climate change, as we pointed outpointed out earlier this week. earlier this week.

There is an up-front cost to addressing climate change, which is why Senate Majority Leader Mitch McConnell (R-Ky.)There is an up-front cost to addressing climate change, which is why Senate Majority Leader Mitch McConnell (R-Ky.)

suggestedsuggested that power generators simply ignore a federal mandate to clean up emissions. (The emissions from power that power generators simply ignore a federal mandate to clean up emissions. (The emissions from power

production are among the largest contributors to the atmospheric gases that are warming the planet.)production are among the largest contributors to the atmospheric gases that are warming the planet.)

There's some psychology at play, too. People are less willing to accept findings that the climate is warming There's some psychology at play, too. People are less willing to accept findings that the climate is warming when it's coldwhen it's cold

outsideoutside. Which is sort of logical, and sort of not. But it means that trying to address climate change during a record cold. Which is sort of logical, and sort of not. But it means that trying to address climate change during a record cold

snap is an uphill battle.snap is an uphill battle.

On Thursday, President Obama On Thursday, President Obama will sign an orderwill sign an order cutting greenhouse gas emissions from the federal government. It will cutting greenhouse gas emissions from the federal government. It will

spur the now-expected response from opponents to such action. Some of them will almost certainly point to the weather inspur the now-expected response from opponents to such action. Some of them will almost certainly point to the weather in

doing so. doing so. It's cold out! How can the climate be warming?It's cold out! How can the climate be warming? The answer: Last month, it was warming dramatically in the least The answer: Last month, it was warming dramatically in the least

politically convenient locations for advocates of moves like Obama's.politically convenient locations for advocates of moves like Obama's.

This has been the warmest winter on record, except in the most politicall... http://www.washingtonpost.com/blogs/the-fix/wp/2015/03/19/this-has-b...

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