Geochemistry of other trace
gases (non-C02 greenhouse
gase
12 340 Global Warming Science
March 20 2012
Dan Cziczo
Reading: Archer, Chapter 4 �
oday�s�Class
• recap the atmosphere and greenhouse concept he other greenhouse gases
•The case of CFCs Recap
�
All others
Argon
Early Atmosphere
Probably� 2 � e�
-�iieely�lost�to�space�early�
Carbon dioxide
Later Atmosphere
�-�lolcanic�out�gassing���
impacts� �� 20 �C02 �S02 �C0 �S2 �Cl2 �
N2 � 2 �N 3 �and�C 4��
Oxygen
Nitrogen
Life
�-�0��C02�balance�
�
Everything else
�11�1��
�
Image by MIT OpenCourseWare.
�
3
iutgens�and� arbuce �����
���������� ��th�editon�
Boundary to space
(1 - α)lsolar
lup, atmosphere
4
ldown, atmosphere
lup, 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
71
240
700
285
2600
Earth
33
251
295
303
1350
Mars
17
216
240
259
600
Image by MIT OpenCourseWare.
4
Modern CO2 This image has been removed due to copyright restrictions. Please see the image on
page http://commons.wikimedia.org/wiki/File:Mauna_Loa_Carbon_Dioxide.png.
5
�PCC�
Solar��rradiance���
1370�W�m2�
(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�
No�Models(�(oe �a�li�le�
modeling�
�
This image has been removed due to copyright restrictions. Please see Figure
6 on page http://onlinelibrary.wiley.com/doi/10.1029/2009JD01210S/full.
(more�in�iecture�17 18 1����
7
Murphy�et�al ��GR�200��
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�
This image has been removed due to copyright restrictions.
9
�PCC�
This image has been removed due to copyright restrictions. Please see the image
on page http://en.wikipedia.org/wiki/File:Greenhouse_Gas_by_Sector.png.
�0
e�
This image has been removed due to copyright restrictions.
11
�
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
What�s�Strange�ubout�methane��
This image has been removed due to copyright restrictions. Please see GEOPHYSICAL
RESEARCH LETTERS 35, L22805 (2008). doi: 10.1029/2008GLD36037.
�3
�4
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
What’s Special About Carbon Dioxide ? (1) CO2 + H2O <-> H+ + HCO3(2) CO2 + H2O + CO3
-2
<-> 2HCO3-
Initial step
~100,000 years
Archer (many papers); review in Solomon et al., PNAS, 2009; Revelle and Suess 1957
�6
Why��
-Climate
system lags (ocean heat uptake) -Nonlinear
spectroscopy for some,
where warming doesn’t
follow the
concentration decay
(CO2, CH4).
Image courtesy of Susan Solomon. Used with permission.
Bern 2.5CC EMIC runs - Solomon et al., PNAS, 2010.
�7
Emit until
2050, then
stop….
Lifetime of N2O ≈
110 years
Lifetime of CH4 ≈ 10
years
Warming due to CO2
persists for more
than 1000 years;
for N2O several
hundred years;
for methane many
decades.
Image courtesy of Susan Solomon. Used with permission.
Bern 2.5CC EMIC runs - Solomon et al., PNAS, 2010. �8
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
2010
2000
1990
1980
1970
1950
1960
100
2010
100
2000
200
1990
200
1980
300
1970
300
1960
400
400
300
Courtesy
This image has been removed due to copyright restrictions. Please see
the image in Solomon� S.� and �. �. Chanin� Science Diplomacy� 2012.
�
20
2010
2000
1990
1980
100
1970
200
1960
1950
400
40�
Gases destroy ozone here�
�
Altitude (km)�
Polar cloud surfaces lead to much
more ozone destruction, in the
heart of the layer�
HCl
20�
20�
Cl
Cl2
ClONO2
ClO Ozone
0�
Image courtesy of Susan Solomon. Used with permission.
Amount of ozone�
Sun+Cold: Both Needed
21
Activated
Reservoirs
for ozone loss
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
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.
Image by MIT OpenCourseWare.
Ramanathan, Science, 1975. Cross-Sections
(Cm2/molecule x 10-18)
Halocarbon Absorption Spectrum
5
4
3
2
1
0
4
6
8
10
12
Atmospheric 'Window'
Wavelength (µm)
HFC-134a
CFC-12
23
14
HCFC-22
Image by MIT OpenCourseWare.
Benefits of Montreal Protocol for Climate�
GWP - Weighted (missions
CO2 emissions
emissions (GtCO2-eq yr-1)
40
30
2.0
Magnitude of
Kyoto Protocol
reduction target
World avoided by the
Montreal Protocol?
20
Reduction Montreal Protocol of
~11 GtCO2-eq/yr
10
�5-6
times global Kyoto target
0
1960
1970
1980
1990
2000
2010
2020
Year
Baseline
CO2
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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RIWKH,QWHUJRYHUQPHQWDO3DQHORQ&OLPDWH&KDQJH7DEOH76&DPEULGJH8QLYHUVLW\3UHVV8VHGZLWKSHUPLVVLRQ
5
Montreal Sep 2007 adjustment: HCFC early phase-out�
Global ODS emissions
4
�
2.0
Emissions ( GtCO2 -eq yr-1)
3
Reducton�in�emissions �
C Cs� transiton��speedup�
2
Magnitude of Kyoto Protocol
reduction target for 2008-2012
1
12-15 GtCO2 -eq
0
1990
2000
2010
2020
2030
2040
2050
Year
Baseline
HCFC reduction
HCFC phase-out adjustment 2007
Image by MIT OpenCourseWare.
26
12-17�GtC02-e �potental�reducton�if�
replaced� ith�lo -GWP�alternatees�or�
reduced�through�consereaton�recycling �
Recap�of� oday�s�Class�
�recap�the�atmosphere�and�greenhouse�concept�
�
he�other�greenhouse�gases�
�
he�case�of�C Cs�
�
7
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� 3340 looaao Warming ccience
cpring 20�
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