Beilman C Cycle GuestLecture Geog401 - University of...
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1/26/2015 1 Geog 401 Climate Change SP15 Carbon Cycle 22 Jan 2015 Dave Beilman, UHM Geography [email protected] Carbon is an important elemental biogeochemical cycle Why should we know or care about carbon and its pools and fluxes? 12 C – stable carbon (light) 13 C – stable carbon (heavy) 14 C – radioactive carbon (even heavier and decays over time) ‘Natural processes [affecting carbon dynamics] are linked to physical conditions, chemical reactions, and biological transformations and they respond themselves to perturbed atmospheric composition and climate change. Therefore, the physical climate system and the biogeochemical cycles of CO 2 , CH 4 and N 2 O are coupled.’ Take home message IPCC 2013 Long-term atmospheric CO 2 from Antarctic ice Luthi et al. 2008. Nature 453: 379 2874 m GEOG 411 – Past Global Change
Transcript of Beilman C Cycle GuestLecture Geog401 - University of...
1/26/2015
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Geog 401 Climate Change SP15Carbon Cycle 22 Jan 2015
Dave Beilman, UHM [email protected]
Carbon is an important elemental biogeochemical cycle
Why should we know or care about carbon and its pools and fluxes?
12C – stable carbon (light)13C – stable carbon (heavy)14C – radioactive carbon (even heavier and decays over time)
‘Natural processes [affecting carbon dynamics] are linked to physical conditions, chemical reactions, and biological transformations and they respond themselves to perturbed atmospheric composition and climate change. Therefore, the physical climate system and the biogeochemical cycles of CO2, CH4 and N2O are coupled.’
Take home message
IPCC 2013
Long-term atmospheric CO2 from Antarctic ice
Luthiet al. 2008. N
ature 453: 379
2874 m
GEOG 411 – Past Global Change
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Fletcher’s (2013) six C cycle processes:
1. Limestone formation in the ocean traps CO2
2CO2 + 2H2O 2HCO3‐ + 2H+
2HCO3‐ + Ca2+ CaCO3 + CO2 + H20
2. Limestone formation in freshwater traps CO2
3. Limestone weathering consumes CO2
CaCO3 + CO2 + H2O Ca2+ + 2HCO3
‐
4. Silicate rock weathering consumes CO2
CaSiO3 + 2CO2 + H2O Ca2+ 2HCO3
‐ + SiO2
5. Photosynthesizing organisms trap CO2and convert it to organic C6CO2 + 6 H2O C6H12O6 + O2
6. Respiration and decomposition or organic C releases CO2
C6H12O6 + O2 6CO2 + 6H2O
Global carbon cycle – pools and fluxes
Inverse relationship between size of pool and flux rate
Fast exchanges with atmosphere, e.g. vegetation
Big, slow exchanges with atmosphere important on long timescales, e.g. rocks
Rud
dim
an E
arth
’s C
limat
e F
ig 3
-3
OM is a complex and varied mixture of organic substancesAll organic substances contain C, ~ ½ of OM is C
Global vegetation: 350-550 Gt CGlobal soils: 1500 -2400 Gt C[Atmosphere: 800 Gt C]
Organic matter and organic C Atmospheric CO2 concentration
scrippsco2.ecsd.edu
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Atmospheric 13CO2 values
scrippsco2.ecsd.edu
…see Fletcher’s Chapter 2 ‘Fingerprint #1’…
Forcings of climate change
The largest contributor to the uptake in energy by the climate system clearly is the increase in atmospheric CO2 concentration since 1750
IPC
C A
R5
(2
013
)
The global carbon cycle
IPC
C A
R5
(2
01
3)
A global balance in fluxes between reservoirs – today’s atmosphere is out of balance owing to anthropogenic C emissions
Black – pre Industrial EraRed – post IE
Case study: impacts of invasive species in Hawai‘i on C dynamics
Is invasion by Sphagnum palustre impacting ecosystem C processes on Ka‘ala?
Partner: O‘ahu Army Natural Resource Program
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Case study: impacts of invasive species in Hawai‘i on C dynamics
Is invasion by Sphagnum palustre impacting ecosystem C processes on Ka‘ala?
What’s next?
Case study: Antarctic terrestrial ecosystem project
Litchfield Island February 2014
Case study: Antarctic terrestrial ecosystem project
atmospheric bomb C
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Case study: Antarctic terrestrial ecosystem project
Galindez Island February 2014
How is plant growth responding to recent rapid warming of the Antarctic Peninsula?
Mahalo!
Additional readingSchlesinger, W.H. 2013. Biogeochemistry: An Analysis of Global Change. 3rd
Edition. Elsevier.
Intergovernmental Panel on Climate Change, Working Group 1. 2013. Chapter 6: Carbon and Other Biogeochemical Cycles.
