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Pollution and Climate Change Accelerate Ocean Degradation

The world's oceans appear to be headed to a new mass extinction event
climate change, global warming, oceans, extinction



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UNITED NATIONS -- A scientific panel issued a report to U.N. member states yesterday indicating that the health of the globe's oceans may be in much worse shape than is widely appreciated.

A combination of factors are threatening a new mass extinction event in the oceans similar to earlier extinctions recorded in the paleontological data, warns a group of marine biologists and climatologists who met recently at Oxford University to share research. Their findings were combined into a report formally presented at a U.N. meeting on fisheries and oceans under way this week.

Among their concerns, the scientists report that the process of ocean acidification, from the absorption of more heat-trapping carbon dioxide emitted by fossil fuel burning, is occurring at a much more rapid rate than previously understood.

Teams of researchers have also recorded increasing rates of ocean hypoxia, or low oxygen levels in the water. And ocean dead zones, believed caused by runoff from agricultural pollution, appear to be growing in size, as well, they say.

The three forces combined -- hypoxia, sea dead zones and climate change -- are creating conditions similar to those found at the start of major die-offs of marine species in the past, suggesting that the world is at the cusp of another mass extinction event, the scientists say. Overfishing, particularly in deep waters and in the areas of the oceans beyond national control, is making the situation for marine animals much worse, the coalition of conservationists fears.

"The magnitude of the cumulative impacts on the ocean is greater than previously understood," report authors write in a summary. "The longer the delay in reducing emissions the higher the annual reduction rate will have to be and the greater the financial cost. Delays will mean increased environmental damage with greater socioeconomic impacts and costs of mitigation and adaptation measures."

The findings were presented to U.N. member states today by the International Union for Conservation of Nature (IUCN) and the International Programme on the State of the Ocean (IPSO).

Ocean changes similar to past extinction causes
"We're seeing changes in the oceans really driven at an extraordinary pace," Alex Rogers, IPSO's scientific director, told reporters on the side of the formal presentation of the study to member states.

The rate of increase of carbon dioxide concentrations in the atmosphere is "much higher than what we've seen in the geological past, and it's certainly much higher than when we saw the last significant extinction event on Earth," he added.

Among the more worrying signs of ecological damage, Rogers and other scientists say, is that the rate at which CO2 is getting absorbed by the oceans is now higher than it was at a point roughly 55 million years ago, when geologists and paleontologists say up to 50 percent of deep-sea species became extinct. Recent studies have also uncovered traces of detergent pollution in Arctic and Antarctic waters, showing that coastal runoff is much more pervasive and widespread than many had assumed.

Past mass marine extinction episodes were "accompanied by major disturbances in the carbon cycle, and we're seeing some symptoms of those types of disturbances now," said Rogers

This week, governments and nonprofits are discussing ocean health in preparation for next year's commemoration of the 20th anniversary of the 1992 Earth Summit in Rio de Janeiro. IUCN and IPSO members said they will use their combined research findings in an effort to press governments to honor previous commitments to enhance ocean ecology and protections.

"We're trying to get governments to take decisions in Rio next year that benefit the oceans," said Sue Lieberman at the Pew Environment Group. "The trend is in the wrong direction. The trend is for a total collapse of marine ecosystems."

The coalition of ocean activists and scientists presenting the findings said they also hoped to use the new report to press nations into enhancing the weak protections offered to major ocean fisheries, particularly in international waters.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

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