Articles | Volume 18, issue 4
Biogeosciences, 18, 1407–1415, 2021
Biogeosciences, 18, 1407–1415, 2021
Technical note
24 Feb 2021
Technical note | 24 Feb 2021

Technical note: Interpreting pH changes

Andrea J. Fassbender et al.

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Cited articles

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Bates, N., Astor, Y., Church, M. J., Currie, K., Dore, J., Gonaález-Dávila, M., Lorenzoni, L., Muller-Karger, F., Olafsson, J., and Santana-Casiano, J. M.: A time-series view of changing ocean chemistry due to ocean uptake of anthropogenic CO2 and ocean acidification, Oceanography, 27, 126–141,, 2014. 
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Short summary
A decline in upper-ocean pH with time is typically ascribed to ocean acidification. A more quantitative interpretation is often confused by failing to recognize the implications of pH being a logarithmic transform of hydrogen ion concentration rather than an absolute measure. This can lead to an unwitting misinterpretation of pH data. We provide three real-world examples illustrating this and recommend the reporting of both hydrogen ion concentration and pH in studies of ocean chemical change.
Final-revised paper