July 5, 2006

BOULDER - Worldwide emissions of carbon dioxide from fossil fuel burning are dramatically altering ocean chemistry and threatening marine organisms, including corals, that secrete skeletal structures and support oceanic biodiversity. A landmark report released today summarizes the known effects of increased atmospheric carbon dioxide on these organisms, known as marine calcifiers, and recommends future research for determining the extent of the impacts.

"It is clear that seawater chemistry will change in coming decades and centuries in ways that will dramatically alter marine life," says Joan Kleypas, the report's lead author and a scientist at the National Center for Atmospheric Research (NCAR) in Boulder. "But we are only beginning to understand the complex interactions between large-scale chemistry changes and marine ecology. It is vital to develop research strategies to better understand the long-term vulnerabilities of sensitive marine organisms to these changes."

The report, "Impacts of Ocean Acidification on Coral Reefs and Other Marine Calcifiers," warns that oceans worldwide absorbed approximately 118 billion metric tons of carbon between 1800 and 1994. Oceans are naturally alkaline, and they are expected to remain so, but the interaction with carbon dioxide is making them less alkaline and more acidic. The increased acidity lowers the concentration of carbonate ion, a building block of the calcium carbonate that many marine organisms use to grow their skeletons and create coral reef structures.

"This is leading to the most dramatic changes in marine chemistry in at least the past 650,000 years," says Richard Feely, one of the authors and an oceanographer at NOAA's Pacific Marine Environmental Laboratory (PMEL) in Seattle.

The report follows a workshop funded by the National Science Foundation and the National Oceanic and Atmospheric Administration, and hosted by the U.S. Geological Survey Integrated Science Center in St. Petersburg, Florida. [...]

Read the full article published on the University Corporation for Atomspheric Research website www.ucar.edu/news/releases/2006/acidification.shtml