Report: Oceans' deteriorating health nearing 'irreversible'

A sobering new report warns that oceans face a "fundamental and irreversible ecological transformation" not seen in millions of years as greenhouse gases and climate change already have affected temperature, acidity, sea and oxygen levels, the food chain and possibly major currents that could alter global weather.

The report, in Science magazine, doesn't break a lot of new ground, but it brings together dozens of studies that collectively paint a dismal picture of deteriorating ocean health.

"This is further evidence we are well on our way to the next great ," said Ove Hoegh-Guldberg, the director of the Global Change Institute at the University of Queensland in Australia and a co-author of the report.

John Bruno, an associate professor of marine sciences at the University of North Carolina at Chapel Hill and the report's other co-author, isn't quite as alarmist, but he's equally concerned.

"We are becoming increasingly certain that the world's are reaching tipping points," Bruno said, adding, "We really have no power or model to foresee" the impact.

The oceans, which cover 71 percent of the Earth's surface, have played a dominant role in regulating the planet's climate. However, even as the understanding of what's happening to terrestrial ecosystems as a result of climate change has grown, studies of marine ecosystems have lagged, the report says. The oceans are acting as a heat sink for rising temperatures and have absorbed about one-third of the carbon dioxide produced by human activities.

Among other things, the report notes:

• The average temperature of the upper level of the oceans has increased more than 1 degree Fahrenheit over the past 100 years, and global ocean surface temperatures in January were the second warmest ever recorded for that month.

• Though the increase in acidity is slight, it represents a "major departure" from the geochemical conditions that have existed in the oceans for hundreds of thousands if not millions of years.

• Nutrient-poor "ocean deserts" in the Pacific and Atlantic oceans grew by 15 percent, or roughly 2.5 million square miles, from 1998 to 2006.

• Oxygen concentrations have been dropping off the Northwest U.S. coast and the coast of southern Africa, where dead zones are appearing regularly. There is paleontological evidence that declining oxygen levels in the oceans played a major role in at least four or five mass extinctions.

• Since the early 1980s, the production of phytoplankton, a crucial creature at the lower end of the food chain, has declined 6 percent, with 70 percent of the decline found in the northern parts of the oceans. Scientists also have found that phytoplankton are becoming smaller.

Volcanic activity and large meteorite strikes in the past have "resulted in hostile conditions that have increased extinction rates and driven ecosystem collapse," the report says. "There is now overwhelming evidence human activities are driving rapid changes on a scale similar to these past events.

"Many of these changes are already occurring within the world's oceans with serious consequences likely over the coming years."

One of the consequences could be a disruption of major ocean currents, particularly those flowing north and south, circulating warm water from the equator to polar regions and cold water from the poles back to the equator. Higher temperatures in polar regions and a decrease in the salinity of surface water due to melting ice sheets could interrupt such circulation, the report says.

The change in currents could further affect such climate phenomena as the El Nino-Southern Oscillation, the Pacific Decadal Oscillation and the North Atlantic Oscillation. Scientists just now are starting to understand how these phenomena affect global patterns.

"Although our comprehension of how this variability will change over the coming decades remains uncertain, the steady increase in heat content in the ocean and atmosphere are likely to have profound influences on the strength, direction and behavior of the world's major current systems," the report says.

Kelp forests such as those off the Northwest U.S. coast, along with corals, sea grasses, mangroves and salt marsh grasses, are threatened by the changes the oceans are undergoing, the report says. All of them provide habitat for thousands of species.

The polar bear isn't the only polar mammal that faces an escalating risk of extinction, the report says; penguin and seal populations also are declining.

"It's a lot worse than the public thinks," said Nate Mantua, an associate research professor at the University of Washington's Climate Impacts Group.

Mantua, who's read the report, said it was clear what was causing the oceans' problems: greenhouse gases. "It is not a mystery," he said.

There's growing concern about low-oxygen or no-oxygen zones appearing more and more regularly off the Northwest coast, Mantua said. Scientists are studying the California Current along the West Coast to determine whether it could be affected, he added.

Richard Feely, a senior scientist with the National Oceanic and Atmospheric Administration's Pacific Marine Environmental Laboratory in Seattle, said the report in Science seemed so direct because one of the authors was Australian.

"Australians come at you full-bore and lay it on the line," Feely said.

Even so, he said, the condition of the oceans is indeed deteriorating.

"The combination of these impacts are tending to show they are additive," he said. "They combine to make things worse."

Asked what the oceans will be like in 50 years if trends aren't reversed, Bruno, the UNC professor, said that all the problems would have accelerated and there would be new ones. For instance, he said tens of thousands of species found only in the Pacific might migrate across the top of North America as the sea ice melts and enter the Atlantic, where they've never been.

Bruno said a 50-year time frame to consider changes in the was way too short, however.

"I am a lot more worried about 200 to 300 years out," he said.

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Jul 05, 2010
Warnings like this are almost useless, except for increasing fear, as the authors themselves admit:

". . . we are well on our way to the next great extinction event, . . . We really have no power or model to foresee".

With kind regards,
Oliver K. Manuel

Jul 05, 2010
How arrogant to presume... its all business as usual.

Jul 05, 2010
There is now overwhelming evidence human activities are driving rapid changes on a scale similar to these past events

And I call BS.

Geothermal activity continues to be the largest contributor to CO2 and other acidifying compounds in the ocean, and I doubt it is even close with all those vents in mid ocean ridges.

These vents that make up mid ocean ridges circle the entire world several times and each one of them pumps super heated water, 200, 300, 400 degrees into the ocean at a rate similar to BP's spill, and these fools continue to think humans play a significant role in temperature rise?

Jul 05, 2010
"Report: Oceans' deteriorating health nearing 'irreversible'"

meh. A 10km diameter bolide slams into the ocean; the latest in a 4.5 billion year long series of large bolides, and the Oceans recovers. Again and again and again.

Jul 05, 2010
Shootist, yes the oceans recover, almost after everything dies. It appears you have no problem being on the list of those species slated for the next one.

Quantum_Conundrum, I have never heard of a delta in ocean geothermal behaviour being linked to increasing ocean acidification. Please cite a source. Also, please comment on this paper: http://210.193.21...848.full

Also, on the polar bears, please reference some real data, study, or some real information instead of a conservative talking points bulletin on the issue. That way we can evaluate your statement with the data.

Marjon, since we're so arrogant to presume that we can and should stop ourselves being on the list for the next major extinction event, I guess you are volunteering to be one of the first to go, eh?

Omatumr, why are warnings like this useless?

Jul 07, 2010
It seems to me that if if we do not try to influence conditions that will influence our environment to our (humans, our society, all the other flora and fauna with which we have co-evolved, etc) detriment, we are no different than the the most primitive of plants and animals which are completely at the mercy of "destiny". And to those too ``superior`` to acknowledge the significance of the mounting evidence, remember it's easy to be a critic- that's why there are so many- but if the fit hits the shan just being able to say ``I told you so` is not going to help much is it?

Jul 08, 2010
"next great extinction event," "

Which means it has happened before. How arrogant to presume humans are a cause or can and should stop it.

Let's see. The last mass extinction was likely caused by the impact that formed the Chicxulub crater, and ~50% of Earth's genera went extinct. Before that was the Triassic-Jurassic extinction (causes unclear, but likely either massive climate change, meteorite impact, or volcanic eruptions), wiping out ~48% of Earth's genera. Before that we have the End-Permian extinction, or the Great Dying, that killed off ~83% of Earth's genera (multiple causes are likely, but massive volcanism and a runaway greenhouse were possibly involved), and finally the two earliest extinction, the Late Devonian and Ordivician-Silurian, that wiped out (respectively) ~50 and ~57% percent of Earth's gener due to unknown causes.

Jul 08, 2010
Just because it's happened before, does not mean it was pleasant. Nor does it mean that it's survivable by us. If an ELE is on the horizon, the only sane thing to do is to devote all possible effort to averting it (including, say, devoting resources to nuclear power. Nuclear may have some nasty side effects, but compared to some of the issues with coal or oil, even an occasional Chernobyl-scale event is not that bad. And...we need energy).

Jul 11, 2010
Well said Ronan. But I think the human animal as it is, is a doomed species. We need a fundamental change at the base level of our neurological makeup in order to enact the sweeping changes necessary in our societies to control our population, waste, food and energy management. All proposed solutions so far are either anathema to our moral outlook (Eugenics, mass pogroms *shudder*) or require the species to become enlightened as a whole (recycling, never reaping more than you sow, love thy neighbor, stop being such a selfish prigg, ect.)
Obviously we know ways to kill off vast amounts of earths populous (nearly unthinkable though), but how do you enlighten every soul on the planet? Genuinely asking that question actually, how would one go about bringing enlightenment to all? Or if not all, how about "How does one ensure that only the enlightened are in charge of the important bits?"

Jul 11, 2010
BTW when I mention recycling i do not mean the Seperate-your-glass-and-plastics kind, I'm speaking of the "I have a plastic bottle that wont rot for damn near ever or break so ill keep useing it till im dead and pass it to my children!" kind.

Jul 11, 2010
I think a viral contagion carrying designer genes to reduce sperm count should work- without symptoms we wouldn't know we were infected.

Seems like Bisphenol-A, phthalates, and PBEs are already taking care of that bit- at least in the developed world.

Already, western culture has greatly reduced the desire to conceive by providing compelling alternatives. Family planning and abortion (1 BILLION since 1922) has brought pop growth to zero in many places.
"How does one ensure that only the enlightened are in charge of the important bits?"
Trust me- They are. Who do you think conceived, funded, and initiated this brilliant campaign around the world?

Otto- don't know if "enlightened" is the proper term- I'd say "pragmatic", but I suppose it's only semantics.

And you're right- another Big War is right around the corner.

Jul 12, 2010
I'd like to see a possibility map and argument diagram for this. Likely in my opinion an ELE is something we can work towards verifying or eliminating as a possibility. Some boundary conditions would be a good place to start. This article seems to indicate we are on several boundary points. Which ones exactly? How do we know we are near a discontinuity and why can't we get a range of possibilities for what's on the other side of the tipping point. we can study individual effects individually and model the combined effects.

what we need is an equation for an ELE that is similar to Drake's equation. Then we need a bunch of people filling in the pieces and expanding and checking the equation until soon enough we have better answers about the future. They need to be verified and duplicable or otherwise supported. Then we need an action plan with cost benefits or ROI assessment that can also be checked and independently verified by all countries and parties.

Jul 12, 2010
How arrogant to presume humans are a cause or can and should stop it.
To presume the opposite is arrogant too and a silly ignorance in addition. Of course we should stop it, or we will kill ourself mutually in ecological crisis and nuclear wars. Especially the India and East Asia should learn, how to limit its population - West Europe has no problem with self-sustaining growth.

Jul 12, 2010

The idea that these things could not have been anticipated is absurd. The idea that there arent pragmatic, enlightened People in the world who would have begun to Prepare for them at the Proper Time is also absurd.

Well, in terms of publicly announced countermeasures for doomsday- Norway and Switzerland have both built "seed arks" and now the EU is planning a Lunar Doomsday Recovery Ark, just in case it gets really bad.

Wouldn't it be ironic if they landed their Arkopod on the moon, only to find that somebody already had the idea a few tens of millenia ago?

Aug 05, 2010
kill ourself mutually in ecological crisis and nuclear wars. Especially the India and East Asia should learn, how to limit its population - West Europe has no problem with self-sustaining growth.

I'm from India and I can confidently assure you that India will not be able to limit it's population. And your Self sustaining Europe is a myth. When the gap between the Have's and Have Not's increases to an alarming and desperate level, the borders will collapse and no one will be secure.

Aug 06, 2010
Technology saving us is still absurd. Govt's will have handful dealing with providing food, shelter, employment and healthcare to the burgeoning populace. Moreover, they will have to fight wars over water, land and oil, so spending on technology will take a back seat and the technology growth will slow down. When govt's fail to provide for the masses, they will collapse leading to anarchy.

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