If the idea of acidic oceans sounds problematic, it should. The carbon emissions that trap heat in the atmosphere also wind up in the ocean, where they dissolve and turn the water acidic. This lowering of the pH of seawater — already underway — threatens coral reefs, shellfish, and the vast food chains to which they belong.

Today 155 scientists issued a report on the rising danger of ocean acidification, saying swift and drastic emissions cuts are needed to curb the problem. The Monaco Declaration [PDF] is based on the work of the Second International Symposium on the Ocean in a High-CO2 World, held in Monaco last October. It’s not the first warning scientists have issued about ocean acidification, though the call to action from scientists from 26 countries is unusually strongly worded:

Ocean acidification could affect marine food webs and lead to substantial changes in commercial fish stocks, threatening protein supply and food security for millions of people as well as the multi-billion dollar fishing industry by mid-century, ocean acidification may render most regions chemically inhospitable to coral reefs. These and other acidification-related changes could affect a wealth of marine goods and services, such as our ability to use the ocean to manage waste, to provide chemicals to make new medicines, and to benefit from its natural capacity to regulate climate.

The report aims to reposition ocean acidification from a peripheral environmental issue to “the other CO2 problem that must be grappled with alongside climate change.” Additionally, as the pH of seawater falls, the process reduces the ocean’s ability to absorb more carbon. Oceans currently absorb one quarter of the CO2 emitted by human activities, the report says.

The solution to acidification is essentially the same as that for climate change — reduce carbon emissions. The declaration’s action points are quite predictable: More research, bring policymakers and economists on board, and enact a global carbon emissions plan. Acidification doesn’t require a separate plan as much as it provides another reason for an aggressive global climate treaty. From the declaration:

Solving this problem will require a monumental worldwide effort. All countries must contribute, and developed countries must lead by example and by engineering new technologies to help solve the problem. Promoting these technologies will be rewarded economically, and prevention of severe environmental degradation will be far less costly for all nations than would be trying to live with the consequences of the present approach where CO2 emissions and atmospheric CO2 concentrations continue to increase, year after year.

The International Geosphere-Biosphere Programme, which helped organize the October summit, didn’t explain its timing on the declaration, though it’s a safe bet the release is designed to build on the momentum of new U.S. leadership. Not only has President Obama declared a return of science to the executive branch, he’s also a bodysurfer from Hawaii who may be inclined to pay attention to oceanic issues. He’s nominated ocean-protection superstar (at least in marine biology circles) Jane Lubchenco to lead the National Oceanic and Atmosphere Administration, though she won’t be confirmed until a commerce secretary is first nominated and confirmed (thank you very much, Bill Richardson).

It’s not clear how scientists involved in acidification research intend to make a broader public-message push this year, though the declaration acknowledges the issue has a lot riding on the COP-15 climate talks in Copenhagen this December.