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Useful vocabulary

Useful vocabulary. Paleo – old or ancient Paleo proxies - preserved physical characteristics of the past that provide information on Earth’s past such as from tree rings, ice cores, fossil pollen, ocean sediments, corals Paleoclimatology – the study of Earth‘s ancient climate.

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Useful vocabulary

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  1. Useful vocabulary • Paleo – old or ancient • Paleo proxies - preserved physical characteristics of the past that provide information on Earth’s past such as from tree rings, ice cores, fossil pollen, ocean sediments, corals • Paleoclimatology – the study of Earth‘s ancient climate.

  2. Climate Change: what you need to know • Describe the difference between climate and weather • Describe basic changes in Earth’s past climate • Discuss basic reasons for Earth’s past climate changes: sunspot cycles and Milankovitch Theory • Discuss how scientists study climate change and how they gather evidence of climate change both past and present • Discuss how current climate change is different from past climate changes

  3. Weather & Climate • Whatisthedifferencebetweenweatherandclimate? • Whataresomefactorsthatdeterminewhattheweather will be? • Whatclimate do you live in? • Write down the questions and take 5 minutes to work with your group to come up with ideas for the answer. • Watch the video • Check your answers http://www.youtube.com/watch?v=wUiwtVSkUwQ

  4. Has Earth’s climate changed in the past – YES! • How many ice ages have occurred? Did humans ever experience an ice age? Explain how you know. • How many warming trends? • Which period are we in now: warming or ice age?

  5. With your group - Make a list of what may have caused Earth’s climate to change in the past.

  6. What caused Earth’s climate to change in the past? • The Earth’s climate is a dynamic interaction between • changes in the amount of energy coming from the sun (sunspot cycles) • the distance and tilt of the Earth to the sun (Milankovitch Theory) • the position and height of the continents • ocean circulation • composition of the atmosphere – the greenhouse gases

  7. The number of sunspots cycles from many to few every 11 years due to the Sun’s changing magnetic field. last solar minimum was 1996 and we entered a period of solar last year (2013). During solar maximums there is a small increase in the energy output from the Sun, and a small increase in global temperatures on Earth and a change in rainfall patterns Our Sun Sunspot = the size of the Earth The Sun on 26 September 2013

  8. Milankovitch Theory • Earth’s tilt changes between 22 - 25 degrees on a cycle of about 41,000 years affects weather: more "tilt" means more severe seasons - warmer summers and colder winters. We are heading to minimum. • The shapeof Earth'sorbit around the sun changesevery 100,000 years with an additional cycle every 400,000 years; Currently Earth’s orbit is closer to being circular. Orbit changes primarily due to the gravitational interaction between Earth, Jupiter, and Saturn. • The precession (wobbles like a top) of Earth’s closest approach to the sun changes on a cycle of about 23,000 years. Currently the closest approach occurs in January, making northern hemisphere winters slightly milder. 11,000 years ago, the closest approach occurred in July, making the seasons more severe than today. Precession occurs primarily due to the gravitational interaction between Earth, Sun, and Moon. http://channel.nationalgeographic.com/channel/videos/ice-age-cycles/ (watch this one) http://www.youtube.com/watch?v=ZD8THEz18gc

  9. How do we know the Earth’s climate has changed in the past and is changing now? – What is the evidence? • Make a list of data scientists might collect how they could study changes in the climate

  10. Evidence of climate change comes from: • Ice Cores: http://www.nhm.ac.uk/nature-online/environmental-change/measuring-climate-change/ice-cores/ • Layers in lake and ocean sediments: http://www.youtube.com/watch?v=oRa-yvQVLrs (start at 2:43) • Temperature records • Sea levels • Glacier Melt: http://www.ted.com/talks/james_balog_time_lapse_proof_of_extreme_ice_loss.html (11:10 - 17:49) • Tree rings http://www.youtube.com/watch?v=Ck5yfj8hOQE • Coral Reefshttps://spark.ucar.edu/coral-studying-past-climate-movie

  11. Has the Earth ever been this warm or CO2 levels this high? • “Modern-day levels of carbon dioxide were last reached about 15 million years ago," Tripati says, when sea levels were at least 25 meters higher and temperatures were at least 3 degrees C warmer on average. Carbon dioxide levels were at values similar to what they are today [330 to 500 ppm], there was substantially less ice at the poles, and the distribution of rainfall was very different.“ (Biello, 2009) Describe what is so different about current climate changes.

  12. How is the current change different? • Average Global Temperatures are rising faster • “In the past century alone, the temperature has climbed 0.7 degrees Celsius, roughly ten times faster than the average rate of ice-age-recovery warming.” (How Is Today’s Warming Different from the Past). • Global CO2 levels are rising faster • "at no time in the last 20 million years have levels of carbon dioxide increased as rapidly as at present," Tripati adds; CO2 concentrations have climbed from 280 ppm to 387 ppm in the past 200 years.(Biello, 2009)

  13. Why? • Human activity and addition to the Greenhouse Gases in our atmosphere: carbon dioxide, methane, nitrous oxide, and chlorofluorcarbons (CFC‘s) “In the Fourth Assessment Report, the Intergovernmental Panel on Climate Change, a group of 1,300 independent scientific experts from countries all over the world under the auspices of the United Nations, concluded there's a more than 90 percent probability that human activities over the past 250 years have warmed our planet.” (Causes) http://www.smithsonianmag.com/video/Climate-Change-101-With-Bill-Nye-the-Science-Guy.html

  14. Further Questions??? • Make a list of questions you still have about climate change and lobal warming

  15. Quizzes to try later • http://www.ecokids.ca/pub/eco_info/topics/climate/quiz/quiz4.cfm (Quiz on climate change) • http://www.ecokids.ca/pub/eco_info/topics/climate/quiz/quiz3.cfm (another quiz)

  16. Resources • Balog, James. "James Balog: Time-lapse Proof of Extreme Ice Loss." TED: Ideas worth Spreading, Sept. 2009. Web. 26 Sept. 2013. <http://www.ted.com/talks/james_balog_time_lapse_proof_of_extreme_ice_loss.html>. • Biello, David. "Just How Sensitive Is Earth's Climate to Atmospheric Carbon Dioxide?" Scientific American. Science, 8 Oct. 2009. Web. 26 Sept. 2013. <http://www.scientificamerican.com/article.cfm?id=how-sensitive-is-climate-to-carbon-dioxide>. • Black, Richard. "Gulf Stream 'is Not Slowing Down'" BBC News. BBC, 29 Mar. 2010. Web. 29 Aug. 2012. <http://news.bbc.co.uk/2/hi/8589512.stm>. • "Causes." Global Climate Change. Ed. Amber Jenkins. NASA, n.d. Web. 26 Sept. 2013. <http://climate.nasa.gov/causes>. • Gardiner, Lisa. "How Do We Investigate Climates of the Past?" Windows to the Universe, 15 June 2009. Web. 26 Sept. 2013. <http://www.windows2universe.org/earth/climate/CDcourses_investigate_climate.html>. • Harms, Nicole. "How to Know If a Website Is Reputable or Not." EHow. Demand Media, 02 Jan. 2010. Web. 28 Aug. 2012. <http://www.ehow.com/how_5824500_website-reputable-not.html>. • Hollowell, Karen. "How to Use Notes to Organize Writing for a Research Paper." EHow. Demand Media, 08 June 2010. Web. 28 Aug. 2012. <http://www.ehow.com/how_6604680_use-organize-writing-research-paper.html>. • "How Is Today’s Warming Different from the Past?" Global Warming : Feature Articles. Ed. Paul Przyborski. Earth Observatory, n.d. Web. 26 Sept. 2013. <http://earthobservatory.nasa.gov/Features/GlobalWarming/page3.php>. • Montecino, Virginia. "Helpful Hints to Help You Evaluate the Credibility of WebResources." Helpful Hints to Help You Evaluate the Credibility of WebResources. N.p., n.d. Web. 28 Aug. 2012. <http://mason.gmu.edu/~montecin/web-eval-sites.htm>. • Powerhouse Museum. "How Do Scientists Measure Climate Change?" Ecologic Powerhouse Museum, n.d. Web. 26 Sept. 2013. <http://www.powerhousemuseum.com/ecologic/the-exhibition/climate-change/how-do-scientists-measure-climate-change/>.

  17. And finally.... • Work on lab reports • Revise for unit test

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