Ocean Acidification – the evil twin of global warming

Oceans slow down global warming but at the cost of “their health”. The oceans absorb approximately 30% of the total CO2 emissions from human activities[1]. However, this CO2 absorption produces a variety of chemical changes in seawater, collectively known as ocean acidification. But Ocean acidification has been labeled as the evil twin of global warming because of its harmful consequences for marine life.

The increased seawater acidity (i.e. pH reduction) produced by the CO2 absorption reduces the concentration of carbonate ions in the ocean. These are the building blocks for marine organisms with shells such as corals (hotspots of biodiversity that support 25% of marine live), shellfish (food sources), and microalgae (base of food webs). As the concentration of carbonate ions decreases, these organisms struggle to build their shells. And, if the decrease in the concentration of carbonate ions is large enough, marine shells can start to dissolve. But should we worry about ocean acidification or can the Earth’s natural processes restore the equilibrium prior to human perturbation?

Last time our planet experienced such fast change in atmospheric CO2 was 252 million years ago, and it took around 10,000 years for natural processes to restore equilibrium[2]. At that time, 90% of all marine species and 70% of all terrestrial species disappeared. It was the largest mass extinction event ever recorded, known as the Permo–Triassic Boundary mass extinction event. Ocean acidification was one of the main players of the extinction of the marine species, and the rate of CO2 released by volcanic eruptions was similar to modern anthropogenic emissions[2]. This fast rate of CO2 release was a critical factor driving ocean acidification[3].

We can prevent the worst-case scenario by reducing CO2 emissions. Industry, governments and citizens must work together to reduce emissions. Oceanic uptake of atmospheric CO2 might reduce global warming, but the resulting ocean acidification is far from positive. Ocean acidification is a global threat that could have dreadful consequences. Everyone can help to maintain a healthy ocean and a healthy planet for our generations and for generations to come. Together we can defeat the EVIL TWIN!

Ocean acidification © bird and moon comics

[1] C. Le Quéré, R. Andrew, P. Friedlingstein, S. Sitch, J. Pongratz, A. Manning, J. Korsbakken, G. Peters, J. Canadell, R. Jackson, T. Boden, P. Tans, O. Andrews, V. Arora, D. Bakker, L. Barbero, M. Becker, R.A. Betts, L. Bopp, F. Chevallier, L.P. Chini, P. Ciais, C.E. Cosca, J. Cross, K. Currie, T. Gasser, I. Harris, J. Hauck, V. Haverd, R.A. Houghton, C.W. Hunt, G. Hurtt, T. Ilyina, A.K. Jain, E. Kato, M. Kautz, R.F. Keeling, K. Klein Goldewijk, A. Körtzinger, P. Landschützer, N. Lefèvre, A. Lenton, S. Lienert, I. Lima, D. Lombardozzi, N. Metzl, F. Millero, P.M.S. Monteiro, D.R. Munro, J.E.M.S. Nabel, S.-I. Nakaoka, Y. Nojiri, X.A. Padín, A. Peregon, B. Pfeil, D. Pierrot, B. Poulter, G. Rehder, J. Reimer, C. Rödenbeck, J. Schwinger, R. Séférian, I. Skjelvan, B.D. Stocker, H. Tian, B. Tilbrook, I.T. van der Laan-Luijkx, G.R. van der Werf, S. van Heuven, N. Viovy, N. Vuichard, A.P. Walker, A.J. Watson, A.J. Wiltshire, S. Zaehle, D. Zhu, «Global Carbon Budget 2017», Earth Syst. Sci. Data Discuss., in review, doi:10.5194/essd-2017-123, 2017.
[2] M. Clarkson, S. Kasemann, R. Wood, T. Lenton, S. Daines, S. Richoz, F. Ohnemueller, A. Meixner, S. Poulton, E. Tippers, «Ocean acidification and the Permo-Triassic mass extinction», Science, 348, 229-232, doi:10.1126/science.aaa0193, 2015.
[3] B. Hönisch, A. Ridgwell, D. Schmidt, E. Thomas, S. Gibbs, A. Sluijs, R. Zeebe, L. Kump, R. Martindale, S. Greene, W. Kiessling, J. Ries, J. Zachos, D. Royer, S. Barker, T. Marchitto Jr., R. Moyer, C. Pelejero, P. Ziveri, G.L. Foster, B. Williams, «The Geological Record of Ocean Acidification», Science, 335, 1058-1063, doi:10.1126/science.1208277, 2012.

Share on Facebook0Tweet about this on TwitterShare on LinkedIn0Share on Tumblr0Share on Google+0Pin on Pinterest0Share on Reddit0

Maribel I. García-Ibáñez

I am a postdoc researcher at Uni Research Climate and the Bjerknes Centre for Climate Research. My main research interests are water masses and the CO2 seawater system in the North Atlantic and Arctic Oceans.I am a postdoc researcher at Uni Research Climate and the Bjerknes Centre for Climate Research. My main research interests are water masses and the CO2 seawater system in the North Atlantic and Arctic Oceans.

Latest posts by Maribel I. García-Ibáñez (see all)

  • Alex

    The main greenhouse gases are CO2, CH4 and N2O. Only the first one can effect on water acidity. A great part of absorbed carbon dioxide is consumed by phytoplankton. Dissolved carbon dioxide is less than 1% of total dissolved inorganic carbon (carbonate and bicarbonate ions). A very small part of dissolved CO2 (about 1/1000) converts to carbonic acid that is a weak acid and produces a small amount of hydrogen ions determining acidity (calculations available). So, where is the proof of CO2 determining role in ocean acidification? Such proof is absent both in the article and in the references.

SciSnack Disclaimer: We write in SciSnack to improve our skills in the art of scientific communication. We therefore welcome comments concerning the clarity, focus, language, structure and flow of our articles. We only accept constructive feedback. All comments are manually approved and anything slightly nasty will not be accepted.