1 / 30

GEOF236 CHEMICAL OCEANOGRAPHY (HØST 2012) Christoph Heinze

GEOF236 CHEMICAL OCEANOGRAPHY (HØST 2012) Christoph Heinze University of Bergen, Geophysical Institute and Bjerknes Centre for Climate Research Prof. in Global Carbon Cycle Modelling Allegaten 70, N-5007 Bergen, Norway Phone: +47 55 58 98 44 Fax: +47 55 58 98 83

thisbe
Download Presentation

GEOF236 CHEMICAL OCEANOGRAPHY (HØST 2012) Christoph Heinze

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. GEOF236 CHEMICAL OCEANOGRAPHY (HØST 2012) ChristophHeinze University of Bergen, Geophysical Institute and Bjerknes Centre for Climate Research Prof. in Global Carbon Cycle Modelling Allegaten 70, N-5007 Bergen, Norway Phone: +47 55 58 98 44 Fax: +47 55 58 98 83 Mobile phone: +47 975 57 119 Email: christoph.heinze@gfi.uib.no DEAR STUDENT AND COLLEAGUE: ”This presentation is for teaching/learning purposes only. Do not useany material ofthispresentation for any purpose outsidecourse GEOF236, ”Chemical Oceanography”, autumn 2012, Universityof Bergen. Thankyou for yourattention.”

  2. Sarmiento&Gruber 2006 Chapter 8: Carbon cycle, part 1

  3. Carbon diamond graphite Broecker, 1985 Degens et al., 1984

  4. The most common elements in sea water The major constituents have almost constant proportion (covary with salinity). changeable ions indicated by arrows From: Treatise in Geochemistry, Vol. 6, Elsevier, 2004

  5. Ocean is vital for governing atmospheric CO2: reservoir size! K.K. Liu et al., 2010 Reservoirs and fluxes in GtC resp. GtC/yr

  6. Global carbon cycle – pool sizes and fluxes IPCC AR4, ch. 7, 2007

  7. Carbon pool sizes and fluxes between the earth system reservoirs For carbon, reservoirs in Pg C, fluxes in Pg C yr-1. [Sundquist and Visser, in Treatise in Geochemistry, Vol. 8, Elsevier, 2004]

  8. Mean annual pCO2 difference surface ocean –atmosphere: Takahashi et al., 2002 Source: Sarmiento&Gruber (2006)

  9. The atmospheric CO2 concentration (past, present, future) Carbon in the Earth system (past glacial/interglacial) What caused these atmospheric CO2 changes ? Question raises a big attribution problem. Siegenthaler et al., 2005,Science CO2 global Tair local EPICA Dome C Taylor DomeVostok

  10. The atmospheric CO2 concentration (past, present) Mauna Loa and ice core curves on anthrop. pCO2 increase Historical atmospheric CO2 record from ice core, Siple Station, Antarctica Neftel, A., H. Friedli, E. Moor, H. Lötscher, H. Oeschger, U. Siegenthaler, and B. Stauffer. 1994. Historical CO2 record from the Siple Station ice core. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A

  11. The atmospheric CO2 concentration (past, present) Mauna Loa and ice core curves on anthrop. pCO2 increase Historical atmospheric CO2 record from ice core, Siple Station, Antarctica Neftel, A., H. Friedli, E. Moor, H. Lötscher, H. Oeschger, U. Siegenthaler, and B. Stauffer. 1994. Historical CO2 record from the Siple Station ice core. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A

  12. Preindustrial niveau 278 ppm

  13. Preindustrial niveau 278 ppm

  14. tropics

  15. Anthropogenic forcing Perturbation of Global Carbon Budget (1850-2006) 2000-2006 fossil fuel emissions 7.6 deforestation 1.5 CO2 flux (Pg C y-1) atmospheric CO2 4.1 land 2.8 ocean 2.2 Time (y) Le Quéré, unpublished; Canadell et al. 2007, PNAS

  16. Mean monthly pCO2 difference surface ocean –atmosphere: Reference year 2000 Takahashi, T., et al., 2009, Climatological mean and decadal change in surface ocean pCO2, and net sea–air CO2 flux over the global oceans, Deep-Sea Research II, 56, 554–577

  17. Mean annual CO2 flux across the air water interface Takahashi, T., et al., 2009, Climatological mean and decadal change in surface ocean pCO2, and net sea–air CO2 flux over the global oceans, Deep-Sea Research II, 56, 554–577

  18. Carbon in seawater – important variables: CO2 hydration 1st 2nd solution dissociation step dissociation step CO2gas + H2O ↔ H2CO3aq ↔ HCO3- + H+ ↔ CO32- + 2H+ carbonic bicarbonate proton carbonate acid ion ion total alkalinity, seawater property determining dissociation of weak acids Alk = [HCO3-] + 2[CO32-] + [B(OH)4-] + [OH-] – [H+] + small terms DIC =[CO2+H2CO3]+[HCO3-] + [CO32-] If 2 of the ”green” variables are known, all the others can be computed. Partial pressure of CO2: pCO2 x solubility = [CO2] dissolved inorganic carbon

  19. In the ocean CO2 is highly reactive due to the ability of seawater to disscociate weak acids: Sea water – buffer system! 1. Dissociation step: CO2 + H2O HCO3- + H+ CO2 + H2O + CO32-(1+x)HCO3- + (1-x)CO32- + (1-x)H+ 2. Dissociation step: CO32- + H+ HCO3- CO2 : HCO3- : CO32- 1 : 100 : 10 Zeebe & Wolf-Gladrow, 2001

  20. How can we quantify the different dissociation reactions? E.g. we would like to know how much [HCO3-], [CO32-], and [H+] would we have in seawater at a specific pCO2 (CO2 partial pressure). Black board

  21. After: Sarmiento&Gruber (2006)

  22. pCO2 pH Harvey, 1955, The chemistry and fertility of seawater, Cambridge University Press.

  23. Global mean dissolved inorganic carbon and alkalinity (horizontal averages): Source: Sarmiento&Gruber (2006)

  24. Dissolved inorganic carbon DIC and alkalinity Alk along the ocean conveyor belt (salinity normalised values): Source: Sarmiento&Gruber (2006)

  25. Property/property plot including DIC: Source: Sarmiento&Gruber (2006)

  26. After: Sarmiento&Gruber (2006)

  27. After: Sarmiento&Gruber (2006)

  28. Carbon pumps Heinze, C., 1990, PhD

More Related