Attributing ocean acidification to major carbon producers

© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Licker, R.; Ekwurzel, B.; Doney, S. C.; Cooley, S. R.; Lima, I. D.; Heede, R.; Frumhoff, P. C. Attributing ocean acidification to major carbon producers. Environmental Research Letters. 14(12), (2019): 124060, doi:10.1088/1748-9326/ab5abc.Recent research has quantified the contributions of CO2 and CH4 emissions traced to the products of major fossil fuel companies and cement manufacturers to global atmospheric CO2, surface temperature, and sea level rise. This work has informed societal considerations of the climate responsibilities of these major industrial carbon producers. Here, we extend this work to historical (1880–2015) and recent (1965–2015) acidification of the world's ocean. Using an energy balance carbon-cycle model, we find that emissions traced to the 88 largest industrial carbon producers from 1880–2015 and 1965–2015 have contributed ~55% and ~51%, respectively, of the historical 1880–2015 decline in surface ocean pH. As ocean acidification is not spatially uniform, we employ a three-dimensional ocean model and identify five marine regions with large declines in surface water pH and aragonite saturation state over similar historical (average 1850–1859 to average 2000–2009) and recent (average 1960–1969 to average of 2000–2009) time periods. We characterize the biological and socioeconomic systems in these regions facing loss and damage from ocean acidification in the context of climate change and other stressors. Such analysis can inform societal consideration of carbon producer responsibility for current and near-term risks of further loss and damage to human communities dependent on marine ecosystems and fisheries vulnerable to ocean acidification.The approach of using equation (1) benefited from discussions with Myles R Allen (University of Oxford) and Inez Fung (University of California, Berkeley). M W Dalton provided insights for the incorporation of the updated carbon producers data. Chloe Ames provided support for references. S Doney acknowledges support from the US National Science Foundation and the University of Virginia Environmental Resilience Institute. R Licker, B Ekwurzel and P C Frumhoff acknowledge the support of the Grantham Foundation for the Protection of the Environment, Wallace Global Fund, and Rockefeller Family Fund to the Union of Concerned Scientists. R Heede gratefully acknowledges the financial support of Wallace Global Fund, Rockefeller Brothers Fund, and Union of Concerned Scientists. We thank two anonymous reviewers for their helpful comments, which greatly improved our manuscript