Study shows rising CO2 levels mean bleak future for marine life
September 1st, 2010A study published in the September issue of the Journal of the Geological Society found that increasing CO2 levels are causing foram diversity to plummet:
A unique ‘natural laboratory’ in the Mediterranean Sea is revealing the effects of rising carbon dioxide levels on life in the oceans. The results show a bleak future for marine life as ocean acidity rises, and suggest that similar lowering of ocean pH levels may have been responsible for massive extinctions in the past.
Rising carbon dioxide levels acidify the ocean, which has a particularly devastating effect on organisms that have calcium carbonate shells, like Foraminifera.The study, published in the September issue of the Journal of the Geological Society, found that increasing CO2 levels caused foram diversity to fall from 24 species to only 4. The study found a tipping point occurs at mean pH 7.8, the pH level predicted for the end of this century.
Forams record past events in the geological record. The Paleocene-Eocene Thermal Maximum (PETM), 55 million years ago, was a period of massive carbon release and rapid warming, accompanied by extinctions in marine life.
This statement by study co-author Dr. Jason Hall-Spencer in the Geological Society’s press release is not optimistic:
Our natural laboratory provides a glimpse into the future of our oceans.
Joseph Romm at Climate Progress has posted this chart showing trends in ocean CO2 concentrations and pH at one sampling station off Hawaii.
Romm also points out that the disappearance of forams has grave implications for the rest of the food chain.
For an analysis of what that could mean, see 2009 Nature Geoscience study concludes ocean dead zones “devoid of fish and seafood” are poised to expand and “remain for thousands of years.”