1. March 2008 Davidson | Dan Yakir, Environmental Sciences Ma Bo’er?

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4. March 2008 Davidson | Stefan Boltzman’s Law: B (Wm -2 )=  T 4

5. March 2008 Davidson | Black body temp -62˚C ! Black body temp -42˚C ! Black body temp -18˚C !

6. March 2008 Davidson | CO2 declined over geological time as…

7. March 2008 Davidson | …our current mild climate was shaped

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10. March 2008 Davidson | 2 ppm/y vs 100 pm/my X20,000 natural rate !

11. March 2008 Davidson | Trajectory of Global Fossil Fuel Emissions Raupach et al. 2007, PNAS 50-year constant growth rates to 2050 B1 1.1%, A1B 1.7%, A2 1.8% A1FI 2.4% Observed 2000-2006 3.3% 2006 2005

12. 19601970198019902000 310 320 340 360 370 380 Carbon Dioxide Concentration (ppmv) 2007 330 350 390

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15. March 2008 Davidson | The temperature/CO2 sensitivity question 10C /100ppm in Antarctica ~5C/100ppm global ~1C/100ppm IPPC IPCC==> ~3C in a century

16. March 2008 Davidson | 19922005 2003-2005

17. March 2008 Davidson | 2005 Larsen Ice shelf collapse

18. March 2008 Davidson | 2005 Larsen Ice shelf collapse

19. March 2008 Davidson | McCarty Glacier, Alaska

20. Sea-level rise

21. March 2008 Davidson | Greenland = West Antarctica = Total for 6m rise = ~ 6 m sea level ~235milion people

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23. Florida’s coast if Greenland OR the West Antarctic Ice Sheet Melted

24. March 2008 Davidson | Alaska beach, 2107? Question of timing… Beetle “fire”…

25. March 2008 Davidson | The turnover time issue: fast in, slow out… (of the atmosphere) 500 ppm CO2 = Different planet Decay of pulse CO2: 100 years => 33% 500 years => 22% 1000 years => 19%

26. March 2008 Davidson | Ma Bo’er? 500 ppm CO2 = Different planet ! Decay of pulse CO2: 100 years => 33% 500 years => 22% 1000 years => 19%

27. March 2008 Davidson | 4.0 + Atmosphere 1.9 + Ocean 2.4 Land 8.3 = Emission The current budget: 50% discount: Things can move much faster… All in billion tons of carbon (Gt C or 10 15 g C)

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29. March 2008 Davidson | Fluxnet: A global project: Dry sites, such as Yatir, are greatly under represented in the network…

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31. March 2008 Davidson | The Yatir Forest

32. March 2008 Davidson | Rain (mm)Carbon (t/ha) Yatir forest: 2902.3 (up to 3.5) Fluxnet (global): ~800 (500-2000) 2.6 t/ha

33. March 2008 Davidson | 13 C derived WUE: feedback from high CO 2 ? ~25% increase in WUE, in dry sites

34. March 2008 Davidson | Below ground… The microbes and the N Back in the lab Pioneer Stable isotopes Ecophysiology ISF, EU, BMBF, MOE, KKL… Where is the water Tree rings Running the show Peace of mind

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37. March 2008 Davidson | … No escape

38. What can you do?

39. March 2008 Davidson | PAR top  PAR top  SWR top  LWR top  Net radiometer top SWR top  PAR t Diffuse radiation

40. March 2008 Davidson | Habitat loss Species extinction Coral bleaching