A scientist is warning excessive greenhouse gas emissions are making the oceans more acidic, putting at risk global fisheries.
Professor Tony Haymet, from the Scripps Institution of Oceanography in California, says organisms that make calcium carbonate shells are a pivotal part of the food chain for fish, and are being affected by the rising acidity.
He says recent research work on carbon dioxide sinks in the oceans indicates there’s a problem.
“We’re most concerned about fisheries, especially because a colleague scientist of ours did an experiment where he measured the acidity in many places off the west coast of North America and found very highly acidic water, about pH 7.75,” he says.
“That’s enough acidity to affect all kinds of parts of the foodweb and any organism in the ocean that makes a shell.
“With snails, that a lot of fish eat, we’re concerned that they won’t be able to excrete their shells anymore.”
[Comment from Jean-Pierre Gattuso: as is often the case, the terminology used in this web page is not right. The definition of “acidic” in the Oxford English dictionary is “having the properties of an acid; having a pH of less than 7”. This definition does not apply to seawater now nor in the foreseeable future. Hence the adjective “acidic” should not be used.]
ABC Rural, 19 August 2008. Article.
