Teaching Earth’s Energy Balance to Students

1. Teaching Earth’s Energy Balance to Students Kim Trenbath Friday, June 11, 2010

2. Overview • My Research and How it Relates to Earth’s Energy Balance • Student Understanding Difficulties • Teaching Suggestions • Activities!

3. Overview • My Research and How it Relates to Earth’s Energy Balance • Student Understanding Difficulties • Teaching Suggestions • Activities!

4. Sun Greenhouse Gases Earth’s Energy Balance Output: Avg Temperature = Albedo

5. Research Methods Research Question 5 Big Picture Topics for Climate Change Understanding The difference between weather and climate, The greenhouse effect, The carbon cycle, Climate feedbacks in the Earth system, and Natural versus anthropogenic climate change. How do students’ climate change conceptions transform throughout a semester of ATOC 1060, a climate change course?

6. Sun 5. Natural versus anthropogenic climate forcings Greenhouse Gases Earth’s Energy Balance Output: Avg Temperature = The Greenhouse Effect The Carbon Cycle Albedo 1. Weather versus Climate. 4. Climate Feedbacks in the Earth System

7. Overview • My Research and How it Relates to Earth’s Energy Balance • Student Understanding Difficulties • Teaching Suggestions • Activities!

8. Possible Difficulties in Student Understanding • Math • The difference between weather and climate • Radiation • Where does the CO2 come from? • The difference between natural versus anthropogenic forcings • Understanding positive and negative climate feedbacks

9. Possible Difficulties in Student Understanding • Math • The difference between weather and climate • Radiation • Where does the CO2 come from? • The difference between natural versus anthropogenic forcings • Understanding positive and negative climate feedbacks

10. Average Yearly Temperatures in Colorado 1900-2009Colorado Climate Report 2008 Example from a 6th Grade Classroom

11. Average global temperatures have increased 0.74 degree C in 100 years* *Average global temperature have increased 0.74 degrees C from 1906 to 1995. (From IPCC 2007 Synthesis Report

12. What’s in YOUR wallet? Dollar Amount 5 3 1 Dollar Amount 2 4 + 6 Jason Rachel Mariah -3 Jason Rachel Mariah +1 +2 +3 + 12 9 9 3 Kim +3 12 3 = $3/person average = $4/person average

13. Average global temperatures have increased 0.74 degree C in 100 years* *Average global temperature have increased 0.74 degrees C from 1906 to 1995. (From IPCC 2007 Synthesis Report

21. El Nino: yr-to-yr variability Volcanoes: cooling (temporary, rare) Effects on temperature The Sun: 11-yr cycles, + drift Humans: lots of warming

22. We have warmed since 2000 We have warmed since 1999 We have cooledsince 1998 We have warmed since 1997 We have warmed since 1996

23. 1998: • Huge El Nino • No volcanoes • Medium sun • Lots of greenhouse gases Some factors that influence the Annual Average Temperature • What if we pick 1992?

24. 2000’s warmer than 1990’s AND: Long term average shows continued warming! 1998 = HUGE El Nino 1992 = volcano REMEMBER: Each year’s “weather” can vary, but the “climate” continues to warm.

25. Possible Difficulties in Student Understanding • Math • The difference between weather and climate • Radiation • Where does the CO2 come from? • The difference between natural versus anthropogenic forcings • Understanding positive and negative climate feedbacks

26. Weather Climate vs. Weather Climate A conceptual description of an area’s expected weather conditions and the extent to which those conditions vary over long time intervals. The state of the atmosphere at a particular time and location involving temperature, precipitation, humidity, and cloud cover.

27. Ski Vacation Define: Climate Beach Vacation

28. Define: Weather

29. Possible Difficulties in Student Understanding • Math • The difference between weather and climate • Radiation • Where does the CO2 come from? • The difference between natural versus anthropogenic forcings • Understanding positive and negative climate feedbacks

30. What is the greenhouse effect? Sun CO2 Visible Light from the Sun Absorbed by CO2 Pass through CO2 CO2 is a Selective Absorber Infrared Radiation from the Earth Emitted Emitted Absorbed by Earth Earth

31. Possible Difficulties in Student Understanding • Math • The difference between weather and climate • Radiation • Where does the CO2 come from? • The difference between natural versus anthropogenic forcings • Understanding positive and negative climate feedbacks

32. HC + O2→ CO2 + H2O + energy Fossil Fuel

34. CO2 concentration increasing NOAA’s Earth System Research Laboratory (http://www.esrl.noaa.gov/gmd/ccgg/iadv/)

35. Possible Difficulties in Student Understanding • Math • The difference between weather and climate • Radiation • Where does the CO2 come from? • The difference between natural versus anthropogenic forcings • Understanding positive and negative climate feedbacks

36. Credit: NASA Goddard Space Flight Center Image by RetoStöckli

37. CO2

38. Climate Forcings Human-Caused (Anthropogenic) Natural The Sun Volcanic eruptions Earth’s orbit around the sun Called Milankovitch cycles • Burning Fossil Fuels • Deforestation • Industrial aerosols • Agriculture • Refrigerants

39. Possible Difficulties in Student Understanding • Math • The difference between weather and climate • Radiation • Where does the CO2 come from? • The difference between natural versus anthropogenic forcings • Understanding positive and negative climate feedbacks

40. Positive Climate Feedback CO2 Ice Water

41. Positive Climate Feedback Ice Water

42. Negative Climate Feedback Visible Light from the Sun Condenses to Form Clouds Reflects Some Sunlight CO2 H2O Water evaporated into the atmosphere Absorbed by Earth

43. Overview • My Research and How it Relates to Earth’s Energy Balance • Student Understanding Difficulties • Teaching Suggestions • Activities!

44. Basic Teaching Suggestions • Link to the science standards. • Address general questions and present basic information up front. • Distinguish among science related information and “policy/economics/other” information. • Use Earth’s Energy Balance to explain climate change.

45. Colorado Academic Standards: Science

46. Address Big Picture First Address Basic Questions First Big Picture Topics First • Is climate change actually happening? • Is climate change completely natural? • How come global warming is not “good”? Earth’s Energy Balance Weather vs. Climate

47. Distinguish between Scientific Evidence and Other Information Science Policy/Economics Should humans mitigate climate change? Carbon Tax Implementing geoengineering. Cost of climate change mitigation and cost of climate change. • Intergovernmental Panel on Climate Change Synthesis Report 2007 • Earth’s energy balance • Average global temperature and precipitation and predicted changes.

48. Earth’s Energy Balance Teaching Suggestions • Teach the simplified model: albedo, greenhouse gases, and sun => average global temperature (affects climate) • What happens if one changes? (“Sensitivity analysis”) • Show how albedo affects temperature. • Emphasize the impact that humans can have on the climate system.

49. Modeling • Activity C: Modeling an Atmosphere’s Effect on a Planet’s Surface Temperature. More complicated models project future climates

50. Sensitivity Analysis Activity B: Experimenting with Computer Models