How does rising atmospheric CO2 affect marine organisms?

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Australia's Great Barrier Reef: Resurrecting Itself, Again and Again and Again
Webster, J.M. and Davies, P.J. 2003. Coral variation in two deep drill cores: significance for the Pleistocene development of the Great Barrier Reef. Sedimentary Geology 159: 61-80.

What was done
Analyses of variations in lithology and coral assemblages of long drill cores made in the northern Great Barrier Reef by the International Consortium for Great Barrier Reef Drilling (Alexander et al., 2001) - one from an inner-shelf reef (Boulder Reef) and one from an outer-shelf reef (Ribbon Reef 5) located 5 and 49 km east of Cooktown on the northeast coast of Australia, respectively - were used to characterize the nature of the Great Barrier Reef throughout the Pleistocene.

What was learned
In the words of the authors, "the repeated occurrence of similar coral assemblages in both drill cores suggests that the Great Barrier Reef has been able to re-establish itself and produce reefs of similar composition again and again over hundreds of thousands of years, despite major environmental fluctuations (i.e. sea-level and temperature changes)."

What it means
These data forcefully demonstrate the ability of coral reefs to reestablish themselves, essentially as originally constituted, even after climatic perturbations as dramatic as those experienced in transitioning from interglacial to ice age to interglacial, again and again and again, and in spite of experiencing long periods of global temperatures more than 2C warmer than those of the present (Petit et al., 1999).

Alexander, I., Andres, M.S., Braithwaite, C.J.R., Braga, J.C., Davies, P.J., Elderfield, H., Gilmour, M.A., Kay, R.L., Kroon, D., McKenzie, J.A., Montaggioni, L.F., Skinner, A., Thompson, R., Vasconcelos, C., Webster, J.M. and Wilson, P.A. 2001. New constraints on the origin of the Australian Great Barrier Reef: results from an international project of deep coring. Geology 29: 483-486.

Petit, J.R., Jouzel, J., Raynaud, D., Barkov, N.I., Barnola, J.-M., Basile, I., Bender, M., Chappellaz, J., Davis, M.., Delaygue, G., Delmotte, M., Kotlyakov, V.M., Legrand, M., Lipenkov, V.Y., Lorius, C., Pepin, L., Ritz, C., Saltzman, E. and Stievenard, M. 1999. Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica. Nature 399: 429-436.

Reviewed 25 February 2004