Warming worries for cod

(Curr. Biol. 16, R474–R475), and from the shift in the chemical equilibria involving the carbonate ion. Wootton's work also highlights the complex dynamics of pH and carbonate changes over time. A lot more research is needed to understand in detail how these changes will play out and how they will interact with wildlife and with the changes in the atmosphere. For instance, it is not at all clear whether the uptake of carbon dioxide by the oceans will provide efficient carbon sequestration in the long term. If calcifying species are severely affected, there will be smaller amounts of carbonate shells going into the sediments, thus the capacity for efficient sequestration may be reduced. Ocean acidification is yet another important reason to do something about the carbon cycle sooner rather than later On the other hand, the time available to find out about these developments is much shorter than researchers previously thought. " Our data show that declining ocean pH is a more urgent problem than has previously been suggested, " Wootton says. " Changing ocean pH should be taken as a serious threat to ocean ecosystems, and its ecological impacts merit increased study. " Described as " the other carbon dioxide problem " by the organisers of the recent meeting at Monaco, ocean acidification is yet another important reason to do something about the carbon cycle sooner rather than later. " Our new results point to irreversible and detrimental impacts to Southern Ocean marine calcifying organisms if atmospheric carbon dioxide exceeds 450 parts per million, " says McNeil. " It provides additional and direct scientific evidence for the world to do everything in its power to limit carbon dioxide concentrations to 450 parts per million in order to avoid the irreversible consequences associated with ocean acidification. " Michael Gross is a science writer based at Oxford. He can be contacted via his web page at www.michaelgross.co.uk While bluefin tuna in the eastern Atlantic and Mediterranean now appear to be under serious threat from overfishing (see page R1110), the populations of cod in the Atlantic have been under threat of collapse for many years, again from overfishing. While some measures have been taken in an effort to restore stocks, the future of the fishery generally remains gloomy. And cod have another problem; some populations may be susceptible to ocean warming that may occur as a result of climate change. It has …