Clarion Call For Marine Life

The new climate-change treaty being negotiated this year must cut carbon dioxide emissions enough to protect oceans from increasing acidity, says the Interacademy Panel on International Issues, a global network of scientific academies.

The panel, which includes the U.S. National Academy of Sciences, says the only practical way to limit the increasing acidity of oceans is to curb atmospheric CO₂, a key greenhouse gas. The panel is calling for global CO₂ emissions to be lowered to at least 50% of 1990 levels by 2050 and continued reductions thereafter.

The cuts the panel is advocating are close to what some industrialized countries have proposed. For instance, President Barack Obama wants to lower U.S. emissions to approximately 83% below 2005 levels by 2050.

Oceans absorb about a quarter of the CO₂ produced by human activity. Rising CO₂ emissions since the Industrial Revolution have lowered the pH of the world's oceans from about 8.2 to 8.1. The falling pH, the panel says, can have profound consequences for marine life, especially those that need calcium carbonate to grow—such as coral and mollusks—and species that feed on them, including fish.

Computer models suggest that the world's coral reefs and polar ecosystems will be seriously harmed by ocean acidification by 2050 if CO₂ emissions are not curtailed, the panel says.