Acidification may push already over-stressed oceans into the red

Rising C02 Concentrations Could Have Increasing Impacts on Key Fisheries and the Billions Depending Upon Them

The future impact of rising emissions on the health of seas and oceans may be far more wide-ranging and complex than was previously supposed, a new report released at the UN climate convention meeting in Mexico says.

The study, entitled the Environmental Consequences of Ocean Acidification, has brought together some of the latest scientific research on ‘ocean acidification’, a process triggered by increasing concentrations of dissolved C02 which is changing the sea’s chemistry by lowering the pH of the marine environment.

Launched by the United Nations Environment Programme (UNEP), the report confirms concerns that some organisms, such as corals and shellfish may find it increasingly difficult to form their skeletons in the decades to come making it harder to survive let alone thrive. It also shows that ocean acidification can react together with ocean warming so that animals such as crabs have a reduced range of temperatures they can thrive in.

Shifting ocean carbonate chemistry during the Eocene-Oligocene climate transition: Implications for deep-ocean Mg/Ca paleothermometry

To date, no conclusive evidence has been identified for intermediate or deep water cooling associated with the >1‰ benthic δ¹⁸O increase at the Eocene-Oligocene transition (EOT) when large permanent ice sheets first appeared on Antarctica. Interpretation of this isotopic shift as purely ice volume change necessitates bipolar glaciation in the early Oligocene approaching that of the Last Glacial Maximum. To test this hypothesis, it is necessary to have knowledge about deep water temperature, which previous studies have attempted to reconstruct using benthic foraminiferal Mg/Ca ratios. However, it appears likely that contemporaneous changes in ocean carbonate chemistry compromised the Mg/Ca temperature sensitivity of benthic foraminifera at deep sites. New geochemical proxy records from a relatively shallow core, ODP Site 1263 (estimated paleodepth of 2100 m on the Walvis Ridge), reveal that carbonate chemistry change across the EOT was not limited to deep sites but extended well above the lysocline, critically limiting our ability to obtain reliable estimates of deep-ocean cooling during that time. Benthic Li/Ca measurements, used as a proxy for [CO₃²⁻], suggest that [CO₃²⁻] increased by ∼29 μmol/kg at Site 1263 across the EOT and likely impacted benthic foraminiferal Mg/Ca. A [CO₃²⁻]–benthic Mg/Ca relationship is most apparent during the early EOT when the overall increase in [CO₃²⁻] is interrupted by an apparent dissolution event. Planktonic δ¹⁸O and Mg/Ca records suggest no change in thermocline temperature and a δ¹⁸O_seawater increase of up to 0.6‰ at this site across the EOT, consistent with previous estimates and supporting the absence of extensive bipolar glaciation in the early Oligocene.

Shellfish under threat from ocean acidification

Certain ocean organisms, particularly shellfish and corals, are losing their ability to form skeletons as a result of increasing “ocean acidification,” a marine environmental problem triggered by accumulating concentrations of dissolved carbon dioxide in the ocean, a new report said.

In turn, some marine species that are dependent or feed on shell-building organisms, including the clown fish, may find it harder to avoid their predators and to make their way home.

These findings were released by the United Nations Environment Program (UNEP) on Thursday at the United Nations Climate Change Conference in Cancun, Mexico.

UCSD scientists warn of ocean acidification in Cancún

Growing Threat To Health Of World’s Oceans

UCSD researchers say action is needed now to keep carbon dioxide from making the world’s oceans more acidic. The scientists are highlighting the problem at a climate summit in Cancún, Mexico.

Scripps Institution of Oceanography researchers say more acid in the ocean depletes calcium carbonate which is needed for corals, snails and other marine life to make their shells.

The director of the Scripps Institution of Oceanography is Tony Haymet.

Oceans threatened by rising acidity and overfishing

Emissions of CO2 don’t just have a negative effect on our climate. Oceans, which absorb a quarter of all carbon dioxide released, have become drastically more acidic in recent years. Should the trend continue, it could have dramatic effects on marine life.

Melting glaciers. Disappearing coastlines. Extreme weather. Climate scientists have been warning for years about the possible effects of global warming — and have a long list of future horrors in store for mankind.

Some effects of climate change, however, are more difficult to see. And with representatives from around the world currently gathered in Cancun, Mexico in yet another attempt to forge an international agreement on how best to tackle the climate problem, the United Nations on Thursday released a study pointing to one of those less visible catastrophes: the state of the world’s oceans.

According to the report, released by the UN Environmental Program (UNEP), the chemistry of the oceans is changing at a rate not seen for 65 million years. Should the rate of change continue unaltered, our oceans could be 150 percent more acidic by the end of this century, the study says.

Jellyfish are taking over the oceans: Population surge as rising acidity of world’s seas kills predators

Britain’s beaches could soon be inundated with records numbers of jellyfish, marine experts warned today.

Scientists say the number of jellyfish are on the rise thanks to the increasing acidity of the world’s oceans.

The warning comes in a new report into ocean acidification – an often overlooked side effect of burning fossil fuel.

Studies have shown that higher levels of carbon dioxide in the atmosphere doesn’t just trigger climate change but can make the oceans more acid.

Since the start of the industrial revolution, acidity levels of the oceans have gone up 30 per cent, marine biologists say.

The new report, published by the UN Environment Programme during the Climate Change talks in Cancun, Mexico, warns that the acidification of oceans makes it harder for coral reefs and shellfish to form skeletons – threatening larger creatures that depend on them for food.

Cancun climate summit: Britain’s salmon at risk from ocean acidification

Britain’s famous salmon runs are in danger from ocean acidification caused by climate change, scientists have warned.

The species rely on tiny shellfish when they go out to sea and feed before returning to rivers like the Tay in Scotland or the Test in Hampshire.

However these sea snails are in danger from ocean acidification.

A United Nations report by the University of Plymouth has warned that fish higher up the food chain like salmon may suffer as a result.

Since the industrial revolution oceans have become 30 per cent more acidic as the water absorbs carbon dioxide and the situation is set to get worse as greenhouse gases increase.

The process, known as ‘ocean acidification’ makes it difficult for shellfish to build their calcium carbonate shells.

Dr Carol Turley, a senior scientist at the UK Ocean Acidification Research Programme at Plymouth University, said studies already show shell fish are struggling to grow.

Climate: UN report highlights ocean acidification

Carbon emissions from fossil fuels may bear a greater risk for the marine environment than thought, with wide-ranging impacts on reproduction, biodiversity richness and fisheries, a report at the UN climate talks here on Thursday said.

Each year, billions of tonnes of carbon dioxide (CO2), the principal greenhouse gas, are absorbed by the sea and are very gradually turning the water more acidic, according to the study launched by the UN Environment Program (UNEP).

In the coming decades, the consequences are likely to be felt throughout the marine food chain, it said.

Rising acidity levels have an impact on calcium-based lifeforms, ranging from tiny organisms called ptetropods that are the primary food source, to crabs, fish, lobsters and coral, it said.

The report was compiled by scientists from Plymouth Marine Laboratory and the National Oceanography Centre in Britain, and the Intergovernmental Oceanographic Commission, part of the UN Educational, Scientific and Cultural Organisation (UNESCO).

Oceans failing the acid test, U.N. says

The chemistry of the world’s oceans is changing at a rate not seen for 65 million years, with far-reaching implications for marine biodiversity and food security, according to a new United Nations study released Thursday.

“Environmental Consequences of Ocean Acidification,” published by the U.N. Environmental Program (UNEP),” warns that some sea organisms including coral and shellfish will find it increasingly difficult to survive, as acidification shrinks the minerals needed to form their skeletons.

Lead author of the report Carol Turley, from the UK’s Plymouth Marine Laboratory said in a statement: “We are seeing an overall negative impact from ocean acidification directly on organisms and on some key ecosystems that help provide food for billions. We need to start thinking about the risk to food security.”

Tropical reefs provide shelter and food for around a quarter of all known marine fish species, according to the U.N. report, while over one billion people rely on fish as a key source of protein.

Ocean acidification may threaten food security: U.N.

Acidification of the seas linked to climate change could threaten fisheries production and is already causing the fastest shift in ocean chemistry in 65 million years, a U.N. study showed on Thursday.

Production of shellfish, such as mussels, shrimp or lobsters, could be most at risk since they will find it harder to build protective shells, according to the report issued on the sidelines of U.N. climate talks in Mexico.

It could also damage coral reefs, vital as nurseries for many commercial fish stocks.

“Ocean acidification is yet another red flag being raised, carrying planetary health warnings about the uncontrolled growth in greenhouse gas emissions,” said Achim Steiner, head of the U.N. Environment Programme (UNEP).