1. Coral Growth in Response to Increased Atmospheric CO 2 Jim Billingsley Biology 881 University of Nebraska, Kearney

2. Introduction Overview Coral Structure Seawater Chemistry Affects of CO 2 on Seawater Conclusions

3. Overview –CO 2 emissions –Physiology of marine organisms.  CO 2  CO 3 2-

4. Overview Photosynthesis and calcification problems Sealevel rise Faster growing algae Boring organisms and storm damage

5. Trends in Atmospheric CO 2 Mauna Loa, Hawaii and Law Dome, Antarctica (Etheridge et al, 1998); (Keeling and Whorf, 2001) Vostok, Antarctica Ice Core Atmospheric CO 2 Record (Petit, et al, 1999)

6. Global Emission of CO 2 (Marland, Boden and Andres 2001)

7. Coral Structure Polyps Colony Nematocysts

8. Coral Structure Animal Calcium carbonate skeleton Symbiotic plant

9. Zooxanthellae Dinoflaggellate Photosynthetic Pigments

10. Seawater Chemistry H 2 O + CO 2 (aq)  H 2 CO 3  HCO 3 - + H +

11. Dissolution of calcium carbonate Temperature, pressure and partial pressure of carbon dioxide CaCO 3 + H 2 0 + CO 2  Ca 2+ + 2HCO 3 - Higher pressures and cooler temperatures Corrosive

12. CO 2 Emissions and Calcification in the Oceans Rising atmospheric CO 2 Carbonate equilibrium Decrease in alkalinity Reduces the CaCO 3 saturation Harder for coral reefs to grow 1880 Present Future – Double CO 2

13. Calculated changes seawater carbonate chemistry ( assuming S=35, TA=3.5 meq/L)  arag CO 2 aq

14. Observations at the Hawaii Ocean Times Series Station

15. Chemical treatments n weeks pCO 2  atm HCO 3 -  mol kg -1 CO 3 2-  mol kg -1 pH sws 29 225  291546  70310  288.23  0.04 47 371  551696  76226  258.05  0.06 43 741  991954  45149  187.81  0.06

16. Effect of CO 2 on community calcification

17. Coral Response (Marubini et al., 2001) 200  atm 700  atm Porites compressa

18. Effect of a doubling in CO 2 (350-700) on calcification, (% decrease) Calcareous macroalgae Amphiroa foliacea-36 Borowitzka, 1981 Porolithon gardineri-16 Agegian, 1985 Corallina pilulifera-44 Gao et al., 1993 Corals Stylophora pistillata -3 Gattuso et al., 1998 Porites porites-16 Marubini & Thake, 1999 Porites compressa-27 Marubini et al., 2001 Acropora sp.-37 Schneider & Erez, 2000 Porites/Montipora-50 Langdon & Atkinson, in prep. Coccolithophorids Emiliania huxleyi -10 Riebesell et al., 2000 Gephyrocapsa oceanica -29 “ “ Natural pop. (N. Pac.) -38 “ “ Emiliania huxleyi -17 Zondervan et al., 2001 Gephyrocapsa oceanica –29 “ “ Community Biosphere 2 -40 Langdon et al., 2000 Monaco mesocosm -21 Leclercq et al., 2000 Bahama Bank -30 Broecker & Takahashi, 1966

19. Future pH Changes Burn all known stocks of fossil fuels –Atmospheric CO 2 would exceed 1,900 parts per million around the year 2300 pH reduction at the ocean surface –Calcium carbonate skeletons Unabated CO 2 emissions – Changes in ocean pH

20. Conclusions  CO 2  Calcification for 200 to 280  atm pCO 2  Calcif.  34% for 350 to 700  atm pCO 2  Calcif.  58%

21. Conclusions Saturation state (  ) controls calcification Consequences of reduced calcification –Space and light –Sealevel rise –Erosion and damage Decomposition of Calcium Carbonate

22. Literature Cited Barker, S., Higgins, J.A., and Elderfield, H. 2003. The future of the carbon cycle: review,calcification response, ballast and feedback on atmospheric CO2. Philosophical Transaction of the Royal Society, 361, 1977–1999. Caldeira, K. and Wickett, M.E. 2003 Oceanography: anthropogenic carbon and ocean pH. Nature, 425, 365. Etheridge, D.M.,,Steele, L.P., R.L. Langenfelds, Francey, R.J., Barnola, J.M., and Morgan, V.I.. 1998. Historical CO 2 records from the Law Dome DE08, DE08-2, and DSS ice cores. 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. Gattuso, J.-P., Allemand, D., and Frankigoulle, M. 1999. Photosynthesis and Calcification at Cellular, Organismal and Community Levels in Coral Reefs: A Review on Interactions and Control by Carbonate Chemistry. American Zoological Society, 39, 160-183. Gerin, F. & Edmunds, B. 2001. Mechanisms of interaction between macroalgae and scleractinians on a coral reef in Jamaica. Journal of Experimental Marine Biology and Ecology, 261, 159–172.

23. Literature Cited Keeling, C.D. and Whorf, T.P. 2005. Atmospheric CO 2 records from sites in the SIO air sampling network. 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. Langdon, C. 2001. Overview of experimental evidence for effects of CO2 on calcification of reef builders. Proceedings of the 9 th International Coral Reef Symposium, Oct 23.27, 2000, Bali Indonesia. Marland, G., Boden, T.A., and Andres, R.J. 2006. Global, Regional, and National Fossil Fuel CO 2 Emissions. 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. Marubini, H., Barnett, C., Langdon, M., and Atkinson, M.J. 2001. Dependence of calcification on light and carbonate ion concentration for the hermatypic coralPorites compressa. Marine Ecology Progress Series, 220, 153–162. Marubini, F., Ferrier-Pages, C., and Cuif, J.-P. 2003. Suppression of skeletal growth in scleractinian corals by decreasing ambient carbonate-ion concentration: a cross-family comparison. Proceedings of the Royal Society of London B, 270, 179–184. Petit, R., Jouzel, J., and Raynaud, D. 1999. Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399, 429-436.