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Global Warming

By: AF. Global Warming. Outline. What is Global Warming? Causes How does it effect us? Slow down Global warming Conclusion. What is Global Warming?. Heating of the Earth Natural and Human Influences . Causes. Natural Natural cycles Milankovitch Cycle Greenhouse effect Humans

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Global Warming

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  1. By: AF Global Warming

  2. Outline What is Global Warming? Causes How does it effect us? Slow down Global warming Conclusion

  3. What is Global Warming? • Heating of the Earth • Natural and Human Influences

  4. Causes • Natural • Natural cycles • Milankovitch Cycle • Greenhouse effect • Humans • Enhanced greenhouse effect

  5. Natural Cycles • Caused by Milankovitch Cycles • Data has been recorded from over past 1 million years • One cycle is 100,000 years • Two parts 80-90% in one, 10-20% in the other • “Ice Age” is 80-90,000 years • “Warming Period” is 10-20,000 years • Current warming is part of the natural cycle • If humans had not had the industrial revolution, we would be in the cooling period

  6. Milankovitch Cycles • Orbit of the Earth • Causes ice ages and warm periods • Ice ages occur every 100,000 years • 3 general factors determine the period • Eccentricity  changes in the orbit around the sun • Obliquity  tilt of the Earth’s axis • Precession  wobble of the Earth’s axis

  7. Milankovitch Cycles Cont. • Two ways the Earth can “sit” • Perihelion  tilt and wobble make the northern hemisphere closer to the sun and causes warming • Aphelion  tilt and wobble make the northern hemisphere farther away from the sun and causes cooling • Eccentricity Cycle • Longest cycle • 100,000 years long • During the cycle, spend less time close to the sun

  8. Milankovitch Cycles Cont. • Obliquity Cycle • Axis stays about 23 ½ degrees, varies 22-24 ½ • Increased obliquity causes hotter summers and cooler winters • Only take a few thousand years for all ice to melt • Decreased obliquity causes cooler summers • Precession Cycle • Wobble is driven by tidal forces which is influenced by the moon • Causes different types of seasons • Hemisphere closest to sun has warm summers and cool winters • Hemisphere away from sun has warm winters and cool summers

  9. Greenhouse Effect • Natural Greenhouse Effect • Garden Greenhouse • Sun passes as light, energy is absorbed, then converted into heat, this warms the greenhouse and the glass traps the heat • 31% incoming radiation reflects back to space • 20% absorbed by the atmosphere • Rest is absorbed into oceans and land • Earth would be 33C colder making the average temperature -18C instead of 15C

  10. Greenhouse Effect Cont. • Human Enhanced Greenhouse Effect • Burning of fossil fuels • CO2, methane, nitrous oxide • From 1990, emissions increased +20% since industrialization • More gases are being produced than can be naturally dealt with • World increase by 1.9% annually between 2001-2025 • Developing countries increase 2.7% annually • Expected to pass first world use by 2018

  11. Greenland Glaciers • 85% of Greenland is covered by a massive ice sheet • Area of 1,736,000 km2, thickness of 1,500 meters, volume of 2,600,000 km3 • If it was to all melt, it would raise sea levels by 6.4 meters • Dr. William Krabill used an airborne laser to survey the altitude of the ice sheet in 1993-1994 and again in 1998-1999 • 51 m3 was lost in between the two tests • Greenland appeared to melting!

  12. Effects Six Degrees Warmer

  13. Slow Down Global Warming

  14. Conclusion • Cannot prevent Global Warming • Do our part to keep Global Warming as natural as it can be

  15. Video Links • http://www.youtube.com/watch?v=ROZJmX73FF4 • http://www.youtube.com/watch?v=oJAbATJCugs • http://www.youtube.com/watch?NR=1&feature=fvwp&v=P-0_gDXqYeQ • http://www.youtube.com/watch?v=6rdLu7wiZOE&feature=fvwp&NR=1 • http://www.youtube.com/watch?NR=1&feature=fvwp&v=skFrR3g4BRQ • http://www.youtube.com/watch?v=7nRf2RTqANg&feature=endscreen&NR=1 • http://www.youtube.com/watch?NR=1&feature=fvwp&v=O8qmaAMK4cM • http://www.youtube.com/user/NationalGeographic?feature=watch#p/search/28/mX3pHD7NH58 • http://www.youtube.com/user/NationalGeographic?feature=watch#p/search/17/7lgZIR-OM48 • http://www.youtube.com/watch?v=7lgZIR-OM48&lr=1&feature=watch If you want to watch these videos, you must copy and paste the link.

  16. Picture Citations • http://live-the-solution.com/mindmaps/ • http://byclive.blogspot.ca/2011/12/global-warming-to-save-mother-earth-or.html • http://geap.wordpress.com/ • http://green4u.wordpress.com/2012/04/18/finally-23-of-american-believe-global-warming/ • http://climate.nasa.gov/kids/bigQuestions/greenhouseEffect/ • http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Greenhouse.shtml • http://www.eia.gov/oiaf/1605/ggccebro/chapter1.html • Not in order of appearance

  17. Bibliographies • Global Warming Natural Cycle. (n.d.). In OSS. Retrieved May 13, 2012, from http://ossfoundation.us/projects/environment/global-warming/natural-cycle • Milankovitch Cycles. (n.d.). In OSS. Retrieved May 13, 2012, from http://ossfoundation.us/projects/environment/global-warming/milankovitch-cycles • Earth's Fidgeting Climate. (n.d.). In NASA Science | Science News. Retrieved May 13, 2012, from http://science.nasa.gov/science-news/science-at-nasa/2000/ast20oct_1/ • Greenhouse Gases. (n.d.). In EIA. Retrieved May 13, 2012, from http://www.eia.gov/oiaf/1605/ggccebro/chapter1.html • Causes of Global Warming. (n.d.). In National Geographic. Retrieved May 13, 2012, from http://environment.nationalgeographic.com/environment/global-warming/gw-causes • The Greeenhouse Effect. (n.d.). In Canada's Action on Climate Change. Retrieved May 13, 2012, from http://www.climatechange.gc.ca/default.asp?lang=En&n=1A0305D5-1 • Climate change 101. (n.d.). In Canada's Action on Climate Change. Retrieved May 13, 2012, from http://www.climatechange.gc.ca/default.asp?lang=En&n=65CD73F4-1

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