Climate Change: An Inter-disciplinary Approach to Problem Solving (CLIMATE 480 // NRE 480)

1. Climate Change: An Inter-disciplinary Approach to Problem Solving(CLIMATE 480 // NRE 480) Richard B. Rood Cell: 301-526-8572 2525 Space Research Building (North Campus) rbrood@umich.edu http://clasp.engin.umich.edu/people/rbrood Winter 2017 March 16, 2017

2. Class Information and News • Canvas site: CLIMATE_480_001_W17 • Record of course • Rood’s Class MediaWiki Site • http://climateknowledge.org/classes/index.php/Climate_Change:_The_Move_to_Action • Rood’s Class Tumblr Site: http://openclimate.tumblr.com

3. Resources and Recommended Reading • Hegerl_Santer_Fingerprint_JClim_1996 • Santer_Attribution_Fingerprint_Nature_1996 • Throughout the presentation

4. Outline: Class 11, Winter 2017 • Attribution • Event attribution • Fingerprinting • Joint Attribution (end-to-end method) • Rosenzweig et al., Nature, 2008 • Focus on the Arctic • Rhetoric

5. Event Attribution • Barriopedro et al., Russian Heat Wave, Science, 2011 • Dole et al., Russian Heat Wave, GRL, 2011 • Rahmstorf, Increase of Extreme Events, PNAS, 2011 • Peterson_Stott_Attribution_2011_Extremes_BAMS_2011 • Shearer and Rood, Earthzine, 2011 • Hoerling, NOAA Brochure

6. Attribution

7. Signal to Noise From Leeds X-ray Imaging

8. Signal to Noise (perhaps more like climate) From social research methods .net

9. Signal to Noise (another example) Noise Signal Signal / Noise Ratio From astronomy and astrophysics .org

10. Some signal to noise issues • We have many sources of variability • Sun, volcanoes, etc. • El Niño, La Niña, etc. • Ice ages, Little Ice Age, Warm Periods, etc. • Land use changes, natural carbon dioxide variability, etc. • How do we detect a trend in temperature and attribute it to human released carbon dioxide?

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

12. Fingerprinting • Barnett_Santer_Ocean_Heat_Attribution_Science_2005 • Santer_Attribution_Fingerprint_Nature_1996 • Hegerl_Santer_Fingerprint_JClim_1996

13. Natural mechanisms influence climate • Changes in the Sun • Changes in the amount of volcanic dust in the atmosphere • Internal variability of the coupled atmosphere and ocean Natural mechanisms Thanks to Ben Santer for Content

14. Thanks to Ben Santer for Content 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)

15. Recent changes in carbon dioxide are largely human-induced Carbon dioxide is the most important greenhouse gas produced by human activities Atmospheric CO2 has increased from a pre-industrial value of about 280 parts per million (ppm) to 379390400 ppm in 20052010 2014 The atmospheric concentration of CO2 in 20052010 2014 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 CO2 since the pre-industrial period Thanks to Ben Santer for Content Source: IPCC AR4 (2007)

16. Thanks to Ben Santer for Content Multiple lines of evidence on which “discernible human influence” conclusions are based • “Basic physics” evidence • Physical understanding of the climate system and the heat-trapping properties of greenhouse gases • 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.) • Paleoclimate evidence • Temperature reconstructions enable us to place the warming of the 20th century in a longer-term context • Fingerprint evidence • Rigorous statistical comparisons between modeled and observed patterns of climate change

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

18. What is “climate fingerprinting”? • 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 Thanks to Ben Santer for Content

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

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

21. “Fingerprinting” with temperature changes in Earth’s atmosphere Model Changes: CO2 + Sulfate Aerosols + Stratospheric Ozone Pressure (hPa) Height (km) Observed Changes Pressure (hPa) Height (km) Temperature changes in oC Santeret al., Nature (1996)

22. Searching for fingerprints of human activities in the world’s oceans • Initial work by Syd Levitus and colleagues showed an increase in the heat content of the oceans over the second half of the 20th 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) Thanks to Ben Santer for Content

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

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

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

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

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

28. Joint Attribution • Rosenzweig et al., Nature, 2008

29. Summary from Rosenzweig et al., Nature, 2008 • shrinking glaciers in every continent • melting permafrost • shifts in the spring peak of river discharge associated with earlier snowmelt • lake and river warming with effects on thermal stratification, chemistry and freshwater organisms • increases in coastal erosion • shifts in spring events (for example, leaf unfolding, blooming date, migration and time of reproduction), species distributions and community structure • demonstrated changes in marine-ecosystem functioning and productivity, including shifts from cold-adapted to warm adapted communities, phenological changes and alterations in species interactions

30. Joint attribution • 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 • Joint Attribution • Documented statistical analysis • Process-level understanding

31. Joint attribution • Joint Attribution • Documented statistical analysis • Process-level understanding • Look to see for biological systems • Unlikely due entirely to natural variability • Consistent with estimated responses of physical or biological variables • Non consistent with alternative, plausible explanations • That are in regions where physical variables, esp. temperature, can also be attributed to climate change • Consistency with behavior of models run with and without carbon dioxide increase

32. Global distribution of changes sensitive to temperatureIPCC Technical Summary WG2

33. Let’s think about the Arctic for a while • WWF: Arctic Feedbacks Assessment • This assessment in 2009 discussed that numerous arctic climate feedbacks will make climate change more severe than indicated by other recent projections, including those of the Intergovernmental Panel on Climate Change Fourth Assessment report (IPCC 2007). • Some of these feedbacks may even interact with each other.

34. Summary from Rosenzweig et al., Nature, 2008 • shrinking glaciers in every continent • melting permafrost • shifts in the spring peak of river discharge associated with earlier snowmelt • lake and river warming with effects on thermal stratification, chemistry and freshwater organisms • increases in coastal erosion • shifts in spring events (for example, leaf unfolding, blooming date, migration and time of reproduction), species distributions and community structure • demonstrated changes in marine-ecosystem functioning and productivity, including shifts from cold-adapted to warm adapted communities, phenological changes and alterations in species interactions

35. Projected Global Temperature Trends: 2100 2071-2100 temperatures relative to 1961-1990. Special Report on Emissions Scenarios Storyline B2 (middle of the road warming). IPCC 2001

36. Arctic Feedback • Atmospheric Circulation Feedbacks • Ocean Circulation • Ice Sheets and Sea-level Rise Feedbacks • Marine Carbon Cycle Feedbacks • Land Carbon Cycle Feedbacks • Methane Hydrate Feedbacks

37. Arctic Feedback • Land Carbon Cycle Feedbacks • Melting permafrost • Greening • Storage ~ 2 x Atmosphere • Methane Hydrate Feedbacks • Frozen methane at sea bed • Permafrost covered by ocean • ~ 13 x Atmosphere

38. Recent Permafrost News • National Geographic: Siberia • InsideClimateNews: Canada

39. NOAA: Arctic Report Card • Arctic Report Card: Landing Page • Arctic Report Card: 2016 • Arctic Report Card: Tundra Greening • Arctic Report Card: Land Carbon Cycle

40. NOAA: Arctic Report Card: Highlights 2016 • The average surface air temperaturefor the year ending September 2016 is by far the highest since 1900, and new monthly record highs were recorded for January, February, October and November 2016. • After only modest changes from 2013-2015, minimum sea ice extentat the end of summer 2016 tied with 2007 for the second lowest in the satellite record, which started in 1979. • Spring snow cover extentin the North American Arctic was the lowest in the satellite record, which started in 1967. • In 37 years of Greenland ice sheetobservations, only one year had earlier onset of spring melting than 2016. • The Arctic Ocean is especially prone to ocean acidification, due to water temperatures that are colder than those further south.  The short Arctic food chain leaves Arctic marine ecosystems vulnerable to ocean acidification events. • Thawing permafrost releases carbon into the atmosphere, whereas greening tundra absorbs atmospheric carbon.  Overall, tundra is presently releasing net carbon into the atmosphere. • Small Arctic mammals, such as shrews, and their parasites, serve as indicators for present and historical environmental variability. Newly acquired parasites indicate northward shifts of sub-Arctic species and increases in Arctic biodiversity.

41. Resources • International Permafrost Association • University of Sussex: Permafrost Lab • Canadian Permafrost Monitoring • USGS Alaskan Permafrost Monitoring • NIH: Permafrost Health • Review Paper: Schuur et al. Terrestrial Carbon and Climate Change, 2008

43. What about the Antarctic • Pine Island Glacier: Wikipedia • Pine Island Glacier: Irreversible • Rood Blog: No Way To Slow Down: 2016045

44. Arctic & Antarctic Takeaways? • When thinking of mitigation, a major goal is to keep the permafrost from melting, keeping the methane hydrates stable, and limiting the ice sheet melt. • Paris and 2 degrees? • Removing CO2 from atmosphere? • There is early melting in the Arctic as heat permeates the system. • Positive feedbacks, more warming, potentially very large • This should worry and motivate people

45. Communication & Rhetoric

46. Communication & Rhetoric Outline • Forms of Rhetoric and Argument • Argumentation • Communication

48. To analyze • Look at the form of argument • Use the principles of the scientific method • Remember the scientific method does not produce facts • Knowledge • Uncertainty (Uncertainty references)

49. Communication of Science-based knowledge • “ … in the case of some people, not even if we had the most accurate scientific knowledge, would it be easy to persuade them …” Aristotle, A Treatise on Rhetoric Important to know when rhetoric is being used as a tactic to achieve a goal.

50. Rhetoric and Form of Argument • Are attacks to discredit the person or field prominent: dishonesty, fraud, conflict of interest, conspiracy • Accusation that ignoring information • Labels: alarmists, warmists, denialists, uneducated, conservative, liberal • Moral levers of trust and distrust • Extract single pieces of information in absence of others and hold as contradiction • Reaching metaphors: The world was warmer and had more carbon dioxide when there dinosaurs and no humans