GLOBAL: Ocean acidification: "the other CO2 problem"

More than 150 marine scientists from universities and research institutes in 26 nations have warned the world's governments to act quickly to reduce the level of carbon dioxide in the ocean, describing the issue as "the other CO2 problem".

The scientists launched the "Monaco Declaration" at the end of January, calling for immediate action to reduce CO2 emissions sharply in order to avoid widespread and severe damage to marine ecosystems from ocean acidification.

The declaration follows last year's international symposium on The Ocean in a High-CO2 World and warned that ocean acidification was already detectable and was accelerating.

"The chemistry is so fundamental and changes are so rapid and severe that impacts on organisms appear unavoidable," said James Orr of the Marine Environment Laboratories and chairman of the symposium. "The questions are now how bad will it be and how soon will it happen."

The declaration said the surface ocean absorbed about one-quarter of the CO2 emitted to the atmosphere from human activities. "As this CO2 dissolves in seawater, it forms carbonic acid, increasing ocean acidity. Since industrialisation began in the 18th century, surface-ocean acidity has increased by 30%," it said.

The declaration warned ocean acidification would damage coral reefs and corrode the shells of sea life:

"This ongoing ocean acidification is decreasing the ability of many marine organisms to build their shells and skeletal structure. Increasing acidity and related changes in seawater chemistry also affect reproduction, behaviour, and general physiological functions of some marine organisms, such as oysters, sea urchins, and squid."

But despite a seemingly bleak outlook, there remained hope, the declaration said: "We have a choice, and there is still time to act if serious and sustained actions are initiated without further delay. First and foremost, policymakers need to realise that ocean acidification is not a peripheral issue.

"It is the other CO2 problem that must be grappled with alongside climate change. Reining in this double threat, caused by our dependence on fossil fuels, is the challenge of the century."

The declaration is available here