Ocean acidification and climate change: advances in ecology and evolution

• Published in: Philosophical Transactions of the Royal Society B: Biological Sciences
• Main Authors: Godbold, J.A., Calosi, P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2013
• Subjects: Ocean acidification
• Online Access: https://eprints.soton.ac.uk/359357/; https://eprints.soton.ac.uk/359357/1/Godbold%2520%2520Calosi_PhilTransRSoc%25202013.pdf

Atmospheric CO2 concentration [CO2] has increased from a pre-industrial level of approximately 280 ppm to approximately 385 ppm, with further increases (700–1000 ppm) anticipated by the end of the twenty-first century [1]. Over the past three decades, changes in [CO2] have increased global average temperatures (approx. 0.2°C decade?1 [2]), with much of the additional energy absorbed by the world's oceans causing a 0.8°C rise in sea surface temperature over the past century. The rapid uptake of heat energy and CO2 by the ocean results in a series of concomitant changes in seawater carbonate chemistry, including reductions in pH and carbonate saturation state, as well as increases in dissolved CO2 and bicarbonate ions [3]: a phenomenon defined as ocean acidification. Time-series and survey measurements [4–6] over the past 20 years have shown that surface ocean pH has reduced by 0.1 pH unit relative to pre-industrial levels, equating to a 26% increase in ocean acidity [3]. Reductions of 0.4–0.5 pH units are projected to occur by the end of the twenty-first century [1] and, while atmospheric [CO2] has consistently fluctuated by 100–200 ppm over the past 800 000 years [7], the recent and anticipated rates of change are unprecedented [8].