Geochemistry of other trace gases (non-c02 greenhouse gase Global Warming Science March Dan Cziczo Reading: Archer, Chapter 4

Transcription

1 Geochemistry of other trace gases (non-c02 greenhouse gase Global Warming Science March Dan Cziczo Reading: Archer, Chapter 4

2 oday s Class recap the atmosphere and greenhouse concept he other greenhouse gases The case of CFCs

3 Recap All others Argon Carbon dioxide Early Atmosphere Probably 2 e - iieely lost to space early Oxygen Later Atmosphere - lolcanic out gassing impacts 2 0 C0 2 S0 2 C0 S 2 Cl 2 N 2 2 N 3 and C 4 Nitrogen Image by MIT OpenCourseWare. 3 Life - 0 C0 2 balance Everything else 11 1 iutgens and arbuce th editon

4 Boundary to space (1 - α)l solar 4 l up, atmosphere l down, atmosphere l up, ground Earth Without Greenhouse Gases We Wouldn't Be Here! Planet α (%) T T observed T 1 layer l solar (K) 5 (K) (K) (Wm -2 ) Venus Earth Mars Image by MIT OpenCourseWare. 4

5 Modern CO2 This image has been removed due to copyright restrictions. Please see the image on page 5

6 PCC Solar rradiance 1370 W m 2 (more in iecture 17 Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, FAQ 2.1, Figure 2. Cambridge University Press. Used with permission. 6 PCC

7 No Models( (oe a li le modeling This image has been removed due to copyright restrictions. Please see Figure 6 on page (more in iecture Murphy et al GR 200

8 Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Figure 6.4. Cambridge University Press. Used with permission. 8 PCC

9 This image has been removed due to copyright restrictions. 9 PCC

10 This image has been removed due to copyright restrictions. Please see the image on page 0 e

11 This image has been removed due to copyright restrictions. 11

12 Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Figure 2.5. Cambridge University Press. Used with permission. 12

13 What s Strange ubout methane This image has been removed due to copyright restrictions. Please see GEOPHYSICAL RESEARCH LETTERS 35, L22805 (2008). doi: /2008GLD

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15 Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Table TS.3. Cambridge University Press. Used with permission. 5

16 What s Special About Carbon Dioxide? (1) CO 2 + H 2 O <-> H + + HCO - 3 Initial step (2) CO 2 + H 2 O + CO -2 3 <-> 2HCO - 3 ~100,000 years Archer (many papers); review in Solomon et al., PNAS, 2009; Revelle and Suess

17 Why -Climate system lags (ocean heat uptake) -Nonlinear spectroscopy for some, where warming doesn t follow the concentration decay (CO 2, CH 4 ). Image courtesy of Susan Solomon. Used with permission. Bern 2.5CC EMIC runs - Solomon et al., PNAS,

18 Lifetime of N 2 O 110 years Lifetime of CH 4 10 years Emit until 2050, then stop. Warming due to CO 2 persists for more than 1000 years; for N 2 O several hundred years; for methane many decades. Image courtesy of Susan Solomon. Used with permission. Bern 2.5CC EMIC runs - Solomon et al., PNAS,

19 Chlorofuorocarbon C C C 0riginally used as a gre gghtng material (replacement of o ygen later used in foam a refrigerant soleent and aerosol propellant!anned due to ozone destructon Image courtesy of Susan Solomon. Used with permission. 9

20 Courtesy This image has been removed due to copyright restrictions. Please see the image in Solomon S. and.. Chanin Science Diplomacy

21 40 Gases destroy ozone here Polar cloud surfaces lead to much more ozone destruction, in the heart of the layer Altitude (km) HCl Cl Cl 2 ClONO 2 ClO Ozone 0 Image courtesy of Susan Solomon. Used with permission. Amount of ozone Activated Reservoirs Sun+Cold: Both Needed for ozone loss 21

22 C Cs and Cs Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Figure 2.6. Cambridge University Press. Used with permission. 22

23 CFCs are strong absorbers of infrared light, and directly contribute to global warming {CFC physics} Greenhouse Effect Due to Chlorofluorocarbons: Climatic Implications Abstract - The infrared bands of chlorofluorocarbons and chlorocarbons enhance the atmospheric greenhouse effect. This enhancement may lead to an appreciable increase in the global surface temperature if the atmospheric concentrations of these compounds reach values of the order of 2 parts per billion. Ramanathan, Science, Halocarbon Absorption Spectrum Image by MIT OpenCourseWare. - S e c ti o n s -18 l e x 1 0 u e )5 4 c3 C ros s /m ol 2 (Cm Wavelength (µm) Atmospheric 'Window' HFC-134a CFC-12 HCFC Image by MIT OpenCourseWare.

24 Benefits of Montreal Protocol for Climate 40 GWP - Weighted missions CO 2 emissions emissions (GtCO 2 -eq yr -1 ) Magnitude of Kyoto Protocol reduction target World avoided by the Montreal Protocol? Reduction Montreal Protocol of ~11 GtCO 2 -eq/yr times global Kyoto target Baseline CO 2 Year Without Montreal Protocol Image by MIT OpenCourseWare. 24 Role of ozone depletion cooling due to CFCs? Could reduce this by perhaps a third but.

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26 Montreal Sep 2007 adjustment: HCFC early phase-out Global ODS emissions 4 Reducton in emissions C Cs transiton speedup GtCO 2 -eq yr -1 ) Emissions ( Magnitude of Kyoto Protocol reduction target for GtC0 2 -e potental reducton if replaced ith lo -GWP alternatees or reduced through consereaton recycling GtCO 2 -eq Year Baseline HCFC reduction HCFC phase-out adjustment 2007 Image by MIT OpenCourseWare. 26

27 Recap of oday s Class recap the atmosphere and greenhouse concept he other greenhouse gases he case of C Cs 7

28 MIT OpenCourseWare looaao Warming ccience cpring 20 For information aaout citing these materiaos or our Terms of Use, visit: