Global declines in coral reef calcium carbonate production under ocean acidification and warming

Authors

Christopher E. Cornwall, Victoria University of Wellington
Steeve Comeau, The University of Western Australia
Niklas A. Kornder, Institute for Biodiversity and Ecosystem Dynamics - Amsterdam
Chris T. Perry, University of Exeter
Ruben van Hooidonk, Rosenstiel School of Marine and Atmospheric Science
Thomas M. DeCarlo, The University of Western Australia
Morgan S. Pratchett, James Cook University
Kristen D. Anderson, James Cook University
Nicola Browne, Curtin University
Robert Carpenter, California State University, Northridge
Guillermo Diaz-Pulido, Griffith University
Juan P. D’Olivo, The University of Western Australia
Steve S. Doo, California State University, Northridge
Joana Figueiredo, Nova Southeastern UniversityFollow
Sofia A.V. Fortunato, James Cook University
Emma Kennedy, Griffith University
Coulson A. Lantz, Southern Cross University
Malcolm T. McCulloch, The University of Western Australia
Manuel González-Rivero, Australian Institute of Marine Science
Verena Schoepf, The University of Western Australia
Scott G. Smithers, James Cook University
Ryan J. Lowe, The University of Western Australia

ORCID

0000-0001-6597-0268

Document Type

Article

Publication Title

Proceedings of the National Academy of Sciences of the United States of America

ISSN

00278424

Publication Date

5-25-2021

Keywords

calcification, Carbonate production, climate change, corals

Abstract

Ocean warming and acidification threaten the future growth of coral reefs. This is because the calcifying coral reef taxa that construct the calcium carbonate frameworks and cement the reef together are highly sensitive to ocean warming and acidification. However, the global-scale effects of ocean warming and acidification on rates of coral reef net carbonate production remain poorly constrained despite a wealth of studies assessing their effects on the calcification of individual organisms. Here, we present global estimates of projected future changes in coral reef net carbonate production under ocean warming and acidification. We apply a meta-analysis of responses of coral reef taxa calcification and bioerosion rates to predicted changes in coral cover driven by climate change to estimate the net carbonate production rates of 183 reefs worldwide by 2050 and 2100. We forecast mean global reef net carbonate production under representative concentration pathways (RCP) 2.6, 4.5, and 8.5 will decline by 76, 149, and 156%, respectively, by 2100. While 63% of reefs are projected to continue to accrete by 2100 under RCP2.6, 94% will be eroding by 2050 under RCP8.5, and no reefs will continue to accrete at rates matching projected sea level rise under RCP4.5 or 8.5 by 2100. Projected reduced coral cover due to bleaching events predominately drives these declines rather than the direct physiological impacts of ocean warming and acidification on calcification or bioerosion. Presently degraded reefs were also more sensitive in our analysis. These findings highlight the low likelihood that the world’s coral reefs will maintain their functional roles without near-term stabilization of atmospheric CO2 emissions.

DOI

10.1073/pnas.2015265118

Volume

118

Issue

21

NSUWorks Citation

Christopher E. Cornwall, Steeve Comeau, Niklas A. Kornder, Chris T. Perry, Ruben van Hooidonk, Thomas M. DeCarlo, Morgan S. Pratchett, Kristen D. Anderson, Nicola Browne, Robert Carpenter, Guillermo Diaz-Pulido, Juan P. D’Olivo, Steve S. Doo, Joana Figueiredo, Sofia A.V. Fortunato, Emma Kennedy, Coulson A. Lantz, Malcolm T. McCulloch, Manuel González-Rivero, Verena Schoepf, Scott G. Smithers, and Ryan J. Lowe. 2021. Global declines in coral reef calcium carbonate production under ocean acidification and warming .Proceedings of the National Academy of Sciences of the United States of America , (21) . https://nsuworks.nova.edu/occ_facarticles/1202.