2. What is it? What is it like inside and why?
Question of the Day
Question: Describe a greenhouse.
What is it? What is it like inside and why?
Answer: … … …
More than 25 types of elements
Turn In:
Air Pressure Lab
p. 605 CYU 2 - 7

3. The Greenhouse Effect

4. Approximately half the light that comes from the sun doesn’t make it to the surface of the earth.

5. X-rays, a lot of incoming IR and UV are absorbed before they reach the surface.

6. Some of the light that reaches the earth’s surface is changed to heat (IR) and is trapped by “Greenhouse Gases” in the atmosphere.

7. How does a Greenhouse work?
Draw this picture noting the difference in wavelength
What’s different about the two waves shown in the picture?
Different wavelengths
Visible light (from the sun)
Has shorter wavelengths
Can pass through glass/ greenhouse gases.
Infrared light (heat)
Has longer wavelengths.
Cannot pass through glass/ greenhouse gases and is reflected back.

8. The Greenhouse Effect on Earth
The greenhouse gases act just like the glass in a greenhouse.

9. The Greenhouse Effect is Good for Life on Earth
Without the Greenhouse Effect
Reflected IR radiation (heat) would be lost to space
Earth’s temperature could vary from about -380 to 250 oF during a day (like on the moon)

10. Greenhouse Gases
Don’t make up a very large percentage of the atmosphere, but have a significant warming effect.

11. Greenhouse Gases CO2 (carbon dioxide) CH4 (methane)
NOx (Nitrous oxides)
CFC’s (Chloroflourocarbons)
H2O (Water Vapor)

12. So What’s The Big Deal??
The human-caused enhancement of the greenhouse effect is called global warming and it’s bad because it’s associated with climate destabilization

13. Runaway Greenhouse Effect
Atmosphere of Venus is mostly CO2
Temperatures can reach
A. 300oF
B. 1000oF
C. 500oF
D. 860oF
Artist’s idea of what Venus’ surface might look like

14. Venus’ Atmosphere

15. CO2 Concentration on Earth
What is the trend of CO2 Concentration in earth’s atmosphere?

16. Global Warming/Climate Change
Even small increases in the amounts of CO2 in the atmosphere can increase our temperature AND change the climate!
Differentiate between weather and climate.

17. Where Does CO2 Come From? Combustion of Fossil Fuels in Power Plants
Cars
Factories

18. Where Does CH4 (methane) Come From?
Naturally occurring in swamps
Released as by-product of rice and cattle farming.

19. Where Does NOx Come From?
Burning of fossil fuels like gasoline, coal, and natural gas
breakdown of fertilizers in soil

20. CFC’s (Chlorofluorocarbons)
Also degrade ozone layer in addition to being a greenhouse gas
Come from
Spray cans (banned from USA spray cans in 1995)
Coolants in refrigeration systems and air conditioners
Solvents to clean electronic components
Blowing agents in the production of plastic foams like styrofoam

21. Where Does H2O (Water Vapor) Come From?
It’s all around us
most abundant greenhouse gas
not directly influenced by human activity (So we don’t worry too much about it!)

22. Which greenhouse gas is most responsible for global warming?
Methane
Water Vapor
CFCs
Carbon Dioxide

23. Effects of Global Warming
Which of the following are probable results of global warming due to excessive greenhouse gases?
thinning of polar ice caps
floods
Droughts/ water shortages
All of the above
 In addition to:
rising sea levels (threatening millions of people)
changing precipitation patterns
heat waves
disruptions of forests and agriculture
Yet we continue this uncontrolled, global experiment!

24. What Can We Do About It? Reduce Greenhouse Gases by:
Use alternative energy that doesn’t emit CO2
Conserve energy by turning off lights, riding bicycles, etc.
Reduce, Reuse & Recycle
And the list goes on!

25. What Can We Do About It?

26. GtC = Gigatons of Carbon emissions = 109 = 1 billion

27. Lab: The Greenhouse Effect

28. p. 605 CYU 2-7

29. p. 605 CYU 2-7
Identify which of the following gases is most abundant in Earth’s atmosphere today.
a. argon c. oxygen
b. nitrogen d. carbon dioxide
2. Nitrogen is most abundant in Earth’s atmosphere today.
More than 25 types of elements
3. Compare Earth’s early atmosphere with its present atmosphere.
3. Earth’s early atmosphere was composed of many gases that would be poisonous to us today. As life forms evolved and began to photosynthesize, oxygen was produced. Once animals adapted to breathing oxygen, they began to give off carbon dioxide, balancing the production of oxygen.

30. p. 605 CYU 2-7
Arrange the steps of the oxygen-carbon dioxide cycle in the correct order:
Animals breathe oxygen
Plants produce oxygen
Plants use carbon dioxide
Animals exhale carbon dioxide
4. The correct order is b, a, d, c.
b. Plants produce oxygen
a. Animals breathe oxygen
d. Animals exhale carbon dioxide
c. Plants use carbon dioxide
More than 25 types of elements

31. p. 605 CYU 2-7
5. Explain why the following statement is incorrect: global warming could cause oceans to rise, so the greenhouse effect must be eliminated completely. 5. If we were to eliminate the greenhouse effect completely, the world’s climate would become too cold for humans to survive.
More than 25 types of elements

32. p. 605 CYU 2-7
6. Predict how much colder it is at the top of Mount Everest, which is almost 9km above sea level, than it is at the Indian coastline. Consider only the difference in altitude. (Hint: the temperature in the troposphere decreases by 6°C/km)
6. The temperature at the top of Mount Everest is about 54°C colder.
9km x 6°C/km = 54°C
More than 25 types of elements

33. p. 605 CYU 2-7
7. In 1982, Larry Walters rose to an altitude of approximately 4900m (just over 3 miles) on a lawn chair attached to 45 helium-filled weather balloons. Give two reasons why Walters’s efforts were dangerous. 7. Walters’s efforts were dangerous because the oxygen content of the air is considerably lower at that altitude and the temperature is extremely cold.
More than 25 types of elements