The concentration of carbon dioxide in the atmosphere is rapidly increasing as we burn fossil fuels. Nobody doubts this. One of the emerging global consequences of this activity is Ocean Acidification (OA); approximately 30% of the CO2 that we emit into the atmosphere is dissolved into the oceans, forming carbonic acid and reducing the pH of the seawater. This is basic chemistry and can already be measured in many marine waters of the world.
The biological and ecological consequences of OA are, however, more complex to understand. Therefore, over the past two decades there has been a dramatic increase in the number of scientific studies investigating the effects of OA. Last week, a review of over 465 of these studies, written by Christopher Cornwall and Catriona Hurd, was published in the ICES Journal of Marine Science. They assessed a number of different scientific methods for rigour and concluded that overall OA science is well designed and executed, and provides useful insights into a complex problem.
There has been some good coverage of Cornwall and Hurd’s paper (e.g. in the journal Nature). Unfortunately, some media outlets misrepresent the findings of the paper. This is of great concern, as the inaccurate and sloppy journalism threatens an essential branch of marine science. I asked Cornwall to write something for this post:
Recently the Daily Mail reported that climate scientists are doom-mongering because their work is flawed. This report is misleading and only serves to introduce misinformation into the public arena.
The Daily Mail quotes an article in Nature by Cressey (2015) that highlights research by Cornwall and Hurd (2015). Science is always evolving, and its aim is to improve both methods and theory in any given field, to be better equipped to answer the most complex of questions. Cornwall and Hurd was merely a call for improvement in only one aspect of research amongst a multitude of methods. The report in the Daily Mail misrepresents our findings. There is overwhelming evidence that the effects of ocean acidification will impact our oceans through reductions in the growth and calcification rates of calcified organisms (e.g. shellfish, corals, etc., that make calcium carbonate ‘skeletons’), and an alteration of the behaviour of other marine invertebrates and fish. This fact is unequivocal. Rather than being “flawed”, the majority of ocean acidification studies have been carried out carefully, using a multitude of methods, and most provide extremely useful and insightful data on this complex problem.
Certainly, the consequences of OA are complex and modified by interactions with other stressors (e.g. nutrient pollution, global warming) and biotic interactions such as herbivory, competition and habitat complexity. This does not mean that the OA science to date is flawed, it simply means that we have more research to do to understand the future impacts. We need to understand all of the effects of OA, from the physiology of single organisms, through population dynamics and up to ecosystem-level interactions. This pattern of discovery is across all of science. For example, Einstein’s theory of relativity is complex. Physicists are making great discoveries but still have research to do. Ocean Acidification is no different.