Long term & short term effects of climate

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Long term & short term effects of climate

  1. 1. Long Term & Short Term Effects of Climate Change<br />By: Sarah Ramanathan <br />Keiran Alam<br />Chantal Liu<br />Manal Rahim<br />
  2. 2. For the past millions of years, our climate has had many significant changes. <br />Changes in Earth's climate are triggered by changes in Earth's energy balance. <br />Long term changes:<br />- continental drift<br />- changes in Earth's orbit<br />Short term changes:<br />- Volcanic eruptions<br />- Air and Ocean Currents  <br />
  3. 3. Long Term Changes in climate(millions of years- hundreds of thousands of years)<br />Chantal & Manal<br />
  4. 4. Plate Tectonics = Theory of explaining slow movement of large plates of Earth's crust<br />Continental Drift - Theory that Earth's continents used to be one supercontinent named Pangaea.<br />225 Million years ago: Pangaea (Permian period)<br />Changes Due to Continental Drift<br />
  5. 5. 200 Million years ago: Laragia and Gondwanaland (Triassic period)<br />135 Million years ago: Jurassic period<br />65 Million years ago: Creations period.<br />
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  8. 8. Continents move = ocean currents and wind patterns change<br /> - Affects heat transfer<br />Affects distribution of land mass<br /> - Nothern Hemisphere (includes Canada) has most land mass.<br />
  9. 9. - Fewer large bodies of water = coldest winters & warmest summers<br /> - More large bodies of water in Southern hemisphere = more moderate climate<br /> - Temperatures weren't like this in Permian period<br />
  10. 10. More mountains (caused by movement of Earth's plates) affects Local & regional climates<br />Wearing of mountains over time can also cause regional climate change<br /> - These changes have occurred in Canada because we have new and old mountain regions such as the Rockies and Appalachians.<br />
  11. 11. Scientists have found that over time the energy the Sun produces over time can also change<br />Changes of area cause complications in production of CO2<br /> - CO2 porduced in volcanoes & mid-ocean trenches.<br /> -> Lost by slowly being absorbed into oceans<br /> -> Areas w/ high overall temperature most likely had greenhouse warming due to volcanic CO2 <br />
  12. 12. Long-Term Cycles in Climate<br />20 000 years ago, Earth had last ice age.<br /> - Temp was 10 degrees lower than today<br /> - Canada covered in ice sheet 3 km thick<br /> - Sea levels dropped as oceans froze over<br /> -> Land under oceans were exposed, revealing hidden bridges to continents<br />
  13. 13. -> Animals crossed over to new habitats<br />Major changes in temp happen in regular cycles (page 349 of textbook)<br /> -warm interglacial periods occur every 100 000 years<br />Interglacial Period - Time between ice ages when Earth warms up<br />
  14. 14. Changes That Occur Over Hundreds Of Thousands Of Years: The Recurrence of Interglacial Periods and Ice Ages<br />every 100,000 years, interglacial periods and ice ages occur<br />Ice age (glacial period): long term reduction of Earth’s temperature = glaciers and ice sheets covering Earth<br />
  15. 15. Interglacial periods: period of warmer temperature that separates periods of time in an ice age<br />Interglacial periods involve movements of glaciers<br />Causes temperatures to keep rising and falling depending on whether glaciers are advancing or retreating<br />
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  17. 17. Why these Interglacial Periods &Ice Ages Keep Happening? <br />Engineer/astronomer Milutin Milankovitch developed theory on reason for these climate changes <br />Earth’s orbit around sun changes on three main ways/cycles:<br />Eccentricity (changing shape) of Earth’s orbit<br />Earth’s Tilt<br />Direction (wobble) of tilt<br />
  18. 18. Eccentricity of the Earth’s orbit<br />Shape of Earth’s orbit around sun changes <br />Goes from almost circular to more elliptical (flattened circle/oval-like)<br />
  19. 19. Caused by Jupiter and Saturn’s gravities<br />Occurs approximately every 100,000 years<br />Earth’s current cycle is more elliptical (oval-like)<br />
  20. 20. Earth’s Tilt<br />Earth’s current tilt = 23.5 degrees<br />Earth’s tilt is responsible for its changes in seasons<br />
  21. 21. Scientists believe that changes in Earth’s tilt are cause for glacial cycles occurring<br />When Earth’s tilt is larger (closer to its 24.5 degrees max):<br />Glaciations end<br />Causes warmer summers<br />Earth’s tilt currently decreasing<br />
  22. 22. In a cycle close to 42,000 years, Earth tilts back and forth on its axis from 22.1 degrees to 24.5 degrees<br />
  23. 23. Direction (wobble) of tilt (Axial Precession)<br />In order to grasp the idea, think of a spinning top<br />
  24. 24. As it spins, it wobbles around/changes direction while spinning on same point<br />Earth’s tilt is similar<br />As Earth’s spins on its axis, it slowly wobbles<br />The angle of its tilt remains approximately the same but its directions changes<br />Cycle of roughly 26,000 years<br />
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  26. 26. Short Term Changes in climate (decades-thousands of years)<br />Sarah & Keiran<br />
  27. 27. Volcanic Eruptions<br />Volcanic eruptions can cause Earth’s climate to change temporarily<br />rocks, dust, and gases are sent out high into atmosphere.<br />
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  30. 30. Suns energy reflects back out to space (from sulfur dioxide particles) <br />Earth’s surface shaded.<br />Amount of cooling depends on amount of dust put in air, and time of cooling-on size of particles. <br />
  31. 31. Ocean Currents<br />Uneven heating of Earth causes convection currents that create prevailing winds and ocean currents. <br />Ocean currents have a strong effect on climates of nearby land<br />Ocean currents can be caused by winds<br />Cold ocean currents cool air above <br />Warm ocean currents heat air above<br />
  32. 32. The global conveyor belt begins around the North Pole and then works its way down, traveling through all of the oceans before circling back<br />Ocean currents can have a major effect on the weather <br />
  33. 33. Air Currents<br />Air on Earth's surface is in constant motion called air currents<br />Air currents affect air quality and ocean currents, and weather conditions<br />Air currents caused by three main processes: <br /><ul><li>temperature change
  34. 34. Impurities
  35. 35. pressure. </li></li></ul><li>
  36. 36. Changes in Sun’s Radiation<br />suns radiation amount drops, Earth gets less energy<br />(less heat =Earth cools down)<br />suns radiation higher=more energy<br />No scientific reason yet why radiation <br /> and over shorter time scales. <br />
  37. 37. Thank You<br />
  38. 38. Bibliography<br />Nelson Science Perspectives 10<br />Nelson Education Ltd.<br />2010<br />Pages 348-353<br /><http://ircamera.as.arizona.edu/NatSci102/NatSci102/lectures/climate.htm>.<br />Windows to the Universe<br />2010 National Earth Science Teachers Association <br />200-2011<br />http://www.windows2universe.org/earth/climate/cli_seasons.html<br />Woods Hole Oceanographic Institution<br />Shelley Dawicki<br />March 28, 2005<br />http://www.whoi.edu/page.do?pid=9779&tid=282&cid=3638&ct=162<br />Long term climate<br />hypertext   G. H. Rieke<br />http://ircamera.as.arizona.edu/NatSci102/NatSci102/lectures/climate.htm<br />
  39. 39. Pictures:<br />Long term climate<br />hypertext   G. H. Rieke<br />http://ircamera.as.arizona.edu/NatSci102/NatSi102/lectures/climate.htm<br />http://www.phy6.org/stargcc/Sconcat2.htm<br />http://room106vjh2.blogspot.com/2010_09_01_archive.html<br />Black, Ken. "How does Ocean Temperature affect Air Temperature?" WiseGeek. Web. 10 Jan 2011. <br />Capital Regional District. "Global Ocean Currents.". Web. 10 Jan 2011. <br />Hayhoe, Christy, Douglas and Katharine. Energy Transfer within the Climate System: Air and Ocean Circulation. Perspectives 10. Canada: Nelson Eduacation Ltd, 2010. 344-348. Print.<br />Exploring the environment<br />Wheeling Jesuit University/NASA-supported Classroom of the Future<br />September 30, 2010<br />http://www.cotf.edu/ete/modules/volcanoes/vclimate.html<br />

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