Ocean Acidification Threatens Biosphere Collapse

While the world’s attention is focused on the upcoming Copenhagen Summit on climate change, marine scientists say the increasing acidification of the world’s oceans poses an even greater threat to the health of the planet.

“In my opinion, acidification is a bigger problem than warming,” said University of Maine professor Robert Steneck in an interview with the Portland Press Herald. “You’re talking about the complete collapse of our biosphere.” And he’s not alone. “Ocean acidification is one of the big environmental threats to marine ecosystems,” said marine scientist Adreas J. Andersson in an interview with Bermuda’s Royal Gazette. He said he hopes the topic will come up at the Copenhagen summit. Scientists have known about the problem for some time, but it has generally received less public attention than global warming. Part of the reason for that may be because the effects are less obvious, and a belief that the ocean’s ability to absorb carbon dioxide will help to control levels of the gas in the atmosphere. Ironically, it is this ability that is leading to the sharp rise in acid levels. Scientists say that the acidity of the oceans had been steady for millions of years, but then suddenly increased by about 30 percent over the past 20 years, resulting in significant changes to the chemistry of the marine environment. Testifying before a congressional committee in 2008, Scott Doney, a senior scientist at the Woods Hole Oceanographic Institute, explained that ocean waters absorb nearly half of the world’s human-generated greenhouse gas emissions. This, in turn, causes a chemical reaction which converts these gases into acids. Most directly affected will be shellfish and coral reefs. Whereas ocean water has been relatively alkaline, enabling formation of calcium deposits needed to build up shells and coral, a more acidic ocean will be more corrosive, hampering the calcium buildup. Moreover, and perhaps more seriously, populations of zooplankton and marine algae will also be affected, disrupting the food chain for many ocean fish and other species. In his remarks, Doney called a for a “balanced approach” to ocean management, one that takes into consideration both the need to control greenhouse gas emissions and ocean acidifications.