1. Climate Change: The Move to Action (AOSS 480 // NRE 480) Richard B. Rood 734-647-3530 2525 Space Research Building (North Campus) rbrood@umich.edu http://aoss.engin.umich.edu/people/rbrood Winter 2010 March 18, 2010

2. Class News Ctools site: AOSS 480 001 W10AOSS 480 001 W10 On Line: 2008 Class2008 Class –Reference list from courseReference list from course Rood Blog Data Base –Series “Getting Ready for Spring” –Series “The Sun”

3. Make Up Class / Opportunity Make up Class on March 22, Rackham Auditorium, 5:00 –John Holdren, President's Science AdvisorJohn Holdren, President's Science Advisor –Please consider this a regular class and make it a priority to attend. Pencil onto calendar on April 6, Jim Hansen, time TBD.

4. Readings on Local Servers Assigned –McCarty: Ecological Consequences of Climate ChangeMcCarty: Ecological Consequences of Climate Change –Walther: Ecological Response to Climate ChangeWalther: Ecological Response to Climate Change Of Interest –Osborn: Spatial Extent of Current WarmingOsborn: Spatial Extent of Current Warming –Francis: Sea Ice and Water Vapor FeedbackFrancis: Sea Ice and Water Vapor Feedback –Anderson: Little Ice Age/Baffin IslandAnderson: Little Ice Age/Baffin Island

5. Next Readings on Local Servers Assigned –Brooks: Framework for Understanding Vulnerability and Adaptive AbilityBrooks: Framework for Understanding Vulnerability and Adaptive Ability Of Interest –Eakin: Building Adaptive CapacityEakin: Building Adaptive Capacity A basic reference –Millennium Ecosystem Assessment Web PortalMillennium Ecosystem Assessment

6. Summary Points: Science Theory / Empirical Evidence CO 2 and Water Vapor Hold Heat Near Surface Correlated Observations CO 2 and Temperature Observed to be strongly related on long time scales (> 100 years) CO 2 and Temperature not Observed to be strongly related on short time scales (< 10 years) Observations CO 2 is Increasing due to Burning Fossil Fuels Theory / Conservation Principle Mass and Energy Budgets  Concept of “Forcing” Prediction Earth Will Warm Validation Consequences Land Use / Land Change Other Greenhouse Gases Aerosols Internal Variability Feedbacks Air Quality “Abrupt” Climate Change

7. Question Madden and Ramanathan Predicted in 1980 would be discernable in 2000. What would you do to evaluate the theory and predictions of global warming? –Surface of planet will warm –Sea level will rise –Weather will change Think about Measurements Feedbacks Correlative behavior Impacts

8. CLOUD-WORLD The Earth System ATMOSPHERE LAND OCEAN ICE (cryosphere) SUN

9. Physical Climate System Last lecture: From Observations –Temperature Surface Upper Atmosphere (cooling) Day – night Record Highs versus Record Lows –Water vapor –Precipitation Intensity –Heat content of ocean –Snow cover –Ice sheets Decreasing Increasing –Sea Ice

10. NCDC Information National Climatic Data Center Weather and Climate Events Research and Monitoring Climate Monitoring Latest Report

11. January 2010

12. IPCC Snow Cover Rood Blog 2 Rood Blog 3

13. IPCC Sea Ice What is happening here?

14. Ice Shelf Collapse January 31, 2002 March 5, 2002

15. Some Icy Link Snow and Ice Data Center State of the Cryosphere

16. Edges “Edges” are places where we really might be able to see things definitively. What are the edges? –Ice (Phase transition) –Deserts –Seasons

17. There is an accumulation of observations Physical and biological impacts correlated with temperature increase and dryer conditions. –What is the relationship between warming and surface dryness? –Strongly correlated with population and where we have looked.

18. Project Budburst A community science activity collect observations of the onset of spring –Project BudburstProject Budburst How to observe the onset of spring –National Phenology NetworkNational Phenology Network

19. Project of Trees A community science activity to collect observations on types of trees –Canadian Plant Hardiness SiteCanadian Plant Hardiness Site

20. How would these changes be revealed?  Changes in vegetation activity can be characterized through 1. changes in growing season 2. changes in “productivity” Increases in Productiviy Increases in growing season JanDecJul Aug Increase NDVI JanDecJul Aug earlier spring delayed fall NDVI From Compton J. Tucker, NASA Goddard

21. Interestingly significant news story

22. Hardiness Map Arbor Day Foundation Maps of Hardiness Zones.Arbor Day Foundation Maps of Hardiness Zones

23. Table 1 from Walther et al. (2002)Walther et al. (2002) Walther, G. R., et al., Ecological Response to Recent Climate Change, Nature, 416, 389-395, 2002Ecological Response to Recent Climate Change

24. Table 2 from Walther et al. (2002)Walther et al. (2002)

25. Spring is coming earlier From Walther et al, 2002Walther et al, 2002

26. Global distribution of changes sensitive to temperature IPCC Technical Summary WG2

27. Can we get a global perspective from satellites? NDVI: Normalized Difference Vegetation Index –Looks at radiative budgets, measurements, and the absorption of photosynthetically active radiation, relative to the rest of the radiation.

28. How would these changes be revealed?  Changes in vegetation activity can be characterized through 1. changes in growing season 2. changes in seasonal NDVI magnitude Increases in NDVI magnitude Increases in growing season JanDecJul Aug Increase NDVI JanDecJul Aug earlier spring delayed fall NDVI From Compton J. Tucker, NASA Goddard

29. Northern Hemisphere May-September NDVI Changes 1992-19991982-1999 From Compton J. Tucker, NASA Goddard

30. From Kirsten de BeuresKirsten de Beures

31. Length of Growing Season From Ranga B. Myneni, Boston University

32. Changes in the Amplitude of the Keeling Curve (Keeling et al, 1996) Amplitude has increased 20% in Hawaii Amplitude has increased 40% in Alaska, Canada The phase, start of the decrease, start of the growing season, has moved forward 7 days.

33. Geographical extent of warming Osborn Spatial Extent of Warming

34. Coherent and Convergent? There is evidence in both the physical climate system and ecosystems of systematic global warming. This evidence shows correlated behavior through many systems. Taken independently each piece could be challenged. Taken together the evidence converges. –Consistent with human-related forcing

35. Coherent and Convergent? Taken independently each piece could be challenged. Taken together the evidence converges. –Consistent with human-related forcing Consistent with human-related forcing –Really?

36. Attribution The physical climate and ecological observations in the previous are consistent with the planet is warming. How do we decide that this is consistent with human-induced warming?

37. Natural mechanisms influence climate Changes in the Sun Changes in the amount of volcanic dust in the atmosphere Internal variability of the coupled atmosphere-ocean system Natural mechanisms Thanks to Ben Santer for Content!Ben Santer

38. Human factors also influence climate Non-natural mechanisms Changes in atmospheric concentrations of greenhouse gases Changes in aerosol particles from burning fossil fuels and biomass Changes in the reflectivity (albedo) of the Earth’s surface Smoke from fires in Guatemala and Mexico (May 14, 1998) Thanks to Ben Santer for Content!Ben Santer

39. Carbon dioxide is the most important greenhouse gas produced by human activities Atmospheric CO 2 has increased from a pre- industrial value of about 280 parts per million (ppm) to 379 ppm in 2005 The atmospheric concentration of CO 2 in 2005 exceeds by far the natural range (180 to 300 ppm) over the last 650,000 years Fossil fuel use is the primary source of the increased concentration of CO 2 since the pre- industrial period Recent changes in carbon dioxide are largely human-induced Source: IPCC AR4 (2007) Thanks to Ben Santer for Content!Ben Santer

40. 1.“Basic physics” evidence –Physical understanding of the climate system and the heat-trapping properties of greenhouse gases 2.Circumstantial evidence –Qualitative agreement between observed climate changes and model predictions of human-caused climate changes (warming of oceans, land surface, and troposphere, stratospheric cooling, water vapor increases, etc.) 3.Paleoclimate evidence –Temperature reconstructions enable us to place the warming of the 20th century in a longer-term context 4.Fingerprint evidence –Rigorous statistical comparisons between modeled and observed patterns of climate change Multiple lines of evidence on which “discernible human influence” conclusions are based Thanks to Ben Santer for Content!Ben Santer

41. Models can perform the “control experiment” that we can’t do in the real world Meehl et al., J. Climate (2004) Average surface temperature change (°C)

42. Strategy: Search for a computer model-predicted pattern of climate change (the “fingerprint”) in observed climate records Assumption:Each factor that influences climate has a different characteristic signature in climate records Method:Standard signal processing techniques Advantage:Fingerprinting allows researchers to make rigorous tests of competing hypotheses regarding the causes of recent climate change What is “climate fingerprinting”? Thanks to Ben Santer for Content!Ben Santer

43. IPCC Temperature Observations Note: It gets smoother away from the surface.

44. Different factors that influence climate have different “fingerprints” 1. Solar 3. Well-mixed greenhouse gases 5. Sulfate aerosol particles 2. Volcanoes 4. Ozone 6. 1 st five factors combined Height (km) Pressure (hPa) °C/century Santer et al., CCSP, 2007

45. “Fingerprinting” with temperature changes in Earth’s atmosphere Model Changes: CO 2 + Sulfate Aerosols + Stratospheric Ozone Height (km) Pressure (hPa) Observed Changes Temperature changes in o C Santer et al., Nature (1996)

46. Ocean Heat Content Ocean Cooling Correction -Outgoing Energy -Sea level rise -Direct comparisons with other observations

47. Initial work by Syd Levitus and colleagues showed an increase in the heat content of the oceans over the second half of the 20 th century (Levitus et al., 2001, Science) Subsequent research by Tim Barnett and colleagues identified a human fingerprint in the observed ocean heat content changes (Barnett et al., 2001, Science) Searching for fingerprints of human activities in the world’s oceans Thanks to Ben Santer for Content!Ben Santer

48. “Fingerprinting” in the ocean: Warming of the North Atlantic over 1955-99 Barnett et al., Science (2005) Thanks to Ben Santer for Content!Ben Santer

49. “Fingerprinting” in the ocean: Warming of the world’s oceans over 1955-99 Barnett et al., Science (2005) Thanks to Ben Santer for Content!Ben Santer

50. Fingerprint detection explained pictorially…. Time-varying observed patternsTime-varying control run patterns t=1 t=2 t=3 t=4 t=n t=1 t=2 t=3 t=4 t=n Projection onto model fingerprint Signal and noise time series Signal-to-noise ratios Projection onto model fingerprint Model fingerprint Thanks to Ben Santer for Content!Ben Santer

51. Human-caused fingerprints have been identified in many different aspects of the climate system Tropospheric temperatures Tropopause height Stratospheric temperaturesSurface specific humidity Ocean temperatures Zonal-mean rainfall Near-surface temperature Sea-level pressure Water vapor over oceans Continental runoff Atmospheric temperature Thanks to Ben Santer for Content!Ben Santer

52. Continental warming likely shows a significant anthropogenic contribution over the past 50 years Key results of IPCC AR4: We are now able to identify human influences on climate at continental scales Thanks to Ben Santer for Content!Ben Santer