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Science: Ocean Acidifying So Fast It Threatens Humanity’s Ability to Feed Itself

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"Science: Ocean Acidifying So Fast It Threatens Humanity’s Ability to Feed Itself"

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The world’s oceans may be turning acidic faster today from human carbon emissions than they did during four major extinctions in the last 300 million years, when natural pulses of carbon sent global temperatures soaring, says a new study in Science. The study is the first of its kind to survey the geologic record for evidence of ocean acidification over this vast time period.

“What we’re doing today really stands out,” said lead author Bärbel Hönisch, a paleoceanographer at Columbia University’s Lamont-Doherty Earth Observatory. “We know that life during past ocean acidification events was not wiped out—new species evolved to replace those that died off. But if industrial carbon emissions continue at the current pace, we may lose organisms we care about—coral reefs, oysters, salmon.”

James Zachos, a paleoceanographer at University of California, Santa Cruz, with a core of sediment from some 56 million years ago, when the oceans underwent acidification that could be an analog to ocean changes today.

Paleoceanographer James Zachos with a core of sediment from some 56 million years ago

That’s the news release from a major 21-author Science paper, “The Geological Record of Ocean Acidification” (subs. req’d).

We knew from a 2010 Nature Geoscience study that the oceans are now acidifying 10 times faster today than 55 million years ago when a mass extinction of marine species occurred. But this study looked back over 300 million and found that “the unprecedented rapidity of CO2 release currently taking place” has put marine life at risk in a frighteningly unique way:

… the current rate of (mainly fossil fuel) CO2 release stands out as capable of driving a combination and magnitude of ocean geochemical changes potentially unparalleled in at least the last ~300 My of Earth history, raising the possibility that we are entering an unknown territory of marine ecosystem change.

That is to say, it’s not just that acidifying oceans spell marine biological meltdown “by end of century” as a 2010 Geological Society study put it. We are also warming the ocean and decreasing dissolved oxygen concentration. That is a recipe for mass extinction. A 2009 Nature Geoscience study found that ocean dead zones “devoid of fish and seafood” are poised to expand and “remain for thousands of years.“

And remember, we just learned from a 2012 new Nature Climate Change study that carbon dioxide is “driving fish crazy” and threatening their survival.

Here’s more on the new study:

The oceans act like a sponge to draw down excess carbon dioxide from the air; the gas reacts with seawater to form carbonic acid, which over time is neutralized by fossil carbonate shells on the seafloor. But if CO2 goes into the oceans too quickly, it can deplete the carbonate ions that corals, mollusks and some plankton need for reef and shell-building.

That is what is happening now. In a review of hundreds of paleoceanographic studies, a team of researchers from five countries found evidence for only one period in the last 300 million years when the oceans changed even remotely as fast as today: the Paleocene-Eocene Thermal Maximum, or PETM, some 56 million years ago. In the early 1990s, scientists extracting sediments from the seafloor off Antarctica found a layer of mud from this period wedged between thick deposits of white plankton fossils. In a span of about 5,000 years, they estimated, a mysterious surge of carbon doubled atmospheric concentrations, pushed average global temperatures up by about 6 degrees C, and dramatically changed the ecological landscape.

The result: carbonate plankton shells littering the seafloor dissolved, leaving the brown layer of mud. As many as half of all species of benthic foraminifers, a group of single-celled organisms that live at the ocean bottom, went extinct, suggesting that organisms higher in the food chain may have also disappeared, said study co-author Ellen Thomas, a paleoceanographer at Yale University who was on that pivotal Antarctic cruise. “It’s really unusual that you lose more than 5 to 10 percent of species over less than 20,000 years,” she said. “It’s usually on the order of a few percent over a million years.” During this time, scientists estimate, ocean pH—a measure of acidity–may have fallen as much as 0.45 units. (As pH falls, acidity rises.)

In the last hundred years, atmospheric CO2 has risen about 30 percent, to 393 parts per million, and ocean pH has fallen by 0.1 unit, to 8.1–an acidification rate at least 10 times faster than 56 million years ago, says Hönisch. The Intergovernmental Panel on Climate Change predicts that pH may fall another 0.3 units by the end of the century,to 7.8, raising the possibility that we may soon see ocean changes similar to those observed during the PETM.

More catastrophic events have shaken earth before, but perhaps not as quickly. The study finds two other times of potential ocean acidification: the extinctions triggered by massive volcanism at the end of the Permian and Triassic eras, about 252 million and 201 million years ago respectively. But the authors caution that the timing and chemical changes of these events is less certain. Because most ocean sediments older than 180 million years have been recycled back into the deep earth, scientists have fewer records to work with.

During the end of the Permian, about 252 million years ago, massive volcanic eruptions in present-day Russia led to a rise in atmospheric carbon, and the extinction of 96 percent of marine life. Scientists have found evidence for ocean dead zones and the survival of organisms able to withstand carbonate-poor seawater and high blood-carbon levels, but so far they have been unable to reconstruct changes in ocean pH or carbonate.

At the end of the Triassic, about 201 million years ago, a second burst of mass volcanism doubled atmospheric carbon. Coral reefs collapsed and many sea creatures vanished. Noting that tropical species fared the worst, some scientists question if global warming rather than ocean acidification was the main killer at this time.

The effects of ocean acidification today are overshadowed for now by other problems, ranging from sewage pollution and hotter summer temperatures that threaten corals with disease and bleaching. However, scientists trying to isolate the effects of acidic water in the lab have shown that lower pH levels can harm a range of marine life, from reef and shell-building organisms to the tiny snails favored by salmon. In a recent study, scientists from Stony Brook University found that the larvae of bay scallops and hard clams grow best at pre-industrial pH levels, while their shells corrode at the levels projected for 2100. Off the U.S. Pacific Northwest, the death of oyster larvae has recently been linked to the upwelling of acidic water there.

In parts of the ocean acidified by underwater volcanoes venting carbon dioxide, scientists have seen alarming signs of what the oceans could be like by 2100. In a 2011 study of coral reefs off Papua New Guinea, scientists writing in the journal Nature Climate Change found that when pH dropped to 7.8, reef diversity declined by as much as 40 percent. Other studies have found that clownfish larvae raised in the lab lose their ability to sniff out predators and find their way home when pH drops below 7.8.

“It’s not a problem that can be quickly reversed,” said Christopher Langdon, a biological oceanographer at the University of Miami who co-authored the study on Papua New Guinea reefs. “Once a species goes extinct it’s gone forever. We’re playing a very dangerous game.”

It may take decades before ocean acidification’s effect on marine life shows itself. Until then, the past is a good way to foresee the future, says Richard Feely, an oceanographer at the National Oceanic and Atmospheric Administration who was not involved in the study. “These studies give you a sense of the timing involved in past ocean acidification events—they did not happen quickly,” he said. “The decisions we make over the next few decades could have significant implications on a geologic timescale.”

This is all on top of the “Climate Story of the Year: Warming-Driven Drought and Extreme Weather Emerge as Key Threat to Global Food Security.”  As my recent piece for the journal Nature concluded, “Feeding some 9 billion people by mid-century in the face of a rapidly worsening climate may well be the greatest challenge the human race has ever faced.”

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26 Responses to Science: Ocean Acidifying So Fast It Threatens Humanity’s Ability to Feed Itself

  1. Doug Bostrom says:

    Sorry, still does not rise to the threshold necessary to stop futilely whining about lethal glue being slathered on our future, forget about being protected by our politicians and instead do something less concerned about dainty half-baked ethics. and more determined to avoid bad outcomes.

  2. Paul Magnus says:

    This indicates that run away greenhouse is a real threat with a probability much higher than we are considering.

  3. Mike Roddy says:

    Don’t worry, the fossil fuel companies are on it. Over on Revkin’s blog, you can read reassuring comments from acidification deniers. Here’s the take home message: shellfish love acid, and those that don’t will adapt!

    Things are getting weird. Journalism no longer exists in the mainstream media.

  4. Rabid Doomsayer says:

    Joe,
    Still a 450′er?

    I know that is unfair, you have indeed changed your position as the evidence comes in. But, this is post is a big link in an almost inescapable chain of logic that only has a few links to go.

  5. Tom King says:

    I’m trying to imagine how the media will misrepresent this. If CO2 is plant food, then acidified oceans are just seltzer.

    • Judy Cross says:

      They used acetic acid to change the pH of the water in the experimental fish tank. That is very different from CO2 enrichment

      • Doug Bostrom says:

        Did you invent that fiction yourself, or are you repeating a silly rumor?

        From the paper:

        Clownfish were reared in either control seawater (pH = 8.15 ± 0.07) or CO2
        -acidified seawater, from the day that eggs were laid until the larvae had reached
        settlement at 11 days post-hatching. To simulate ocean acidification the pH of treatment seawater was adjusted to 7.8 ± 0.05 in both the breeding aquariums and the larval rearing aquariums as described by Munday et al. (2009a). Briefly, an electronic pH-controller (Tunze, Aquarientechnik, Germany) was attached to each aquarium to maintain pH at 7.8 by CO2 injection. The pH controller was connected to a laboratory-grade glass pH probe in the aquarium and to an electronic solenoid connected to a cylinder of CO2 . The solenoid injected a slow stream of CO2
        into a diffuser (Red Sea CO2 Reaktor 500, Red Sea Co., Houston, USA) at the bottom of the aquarium whenever the pH of the aquarium seawater rose above 7.8. pH was
        maintained within ± 0.05 units of the desired level and there was no detectable gradient in seawater pH within the aquarium.

        Why would somebody just make up a fantasy version of the experiment?

        • Judy Cross says:

          There have been numerous experiments. If you are referring to: Munday, P.L., Donelson, J.M., Dixson, D.L. and Endo, G.G.K. 2009. Effects of ocean acidification on the early life history of a tropical marine fish. Proceedings of the Royal Society B 276: 3275-3283, there were beneficial effects from higher CO2 levels.
          “The four researchers, all from the School of Marine and Tropical Biology of Australia’s James Cook University, determined that “CO2 acidification had no detectable effect on embryonic duration, egg survival and size at hatching.” In fact, they say that it actually “tended to increase [italics added] the growth rate of larvae.” Eleven days after hatching, for example, they observed that “larvae from some parental pairs were 15 to 18 per cent longer and 47 to 52 per cent heavier in acidified water compared to controls,” further noting there was a “positive [italics added] relationship between length and swimming speed,” and that “large size is usually considered to be advantageous for larvae and newly settled juveniles.”

          • Mark says:

            No doubt some folks will celebrate if gooey eggs appear to benefit!

            Forming carbonate structures required to reach reproductive age, and forming those structures in an increasingly acidic environment?

            Well! Since the little gooey buggers at the start of the journey BENEFIT that ((obviously)) negates the fatal impact on the same little buggers later in life. So all is good! Drill, baby, drill.

          • Doug Bostrom says:

            Yes, wonderful, bu why and how did you end up repeating your first concoction, which an inaccurate characterization of the actual reference Romm mentioned?

            I’m not diving down the 2nd rabbit hole until the first one is filled in properly.

          • WyrdWays says:

            So one study shows that ocean acidification has, in the geologic past, pulled a pillar (benthic foraminifera)out of the marine food pyramid – and mass extinction followed.

            And you’re quoting an experiment that shows some tropical marine fish do better, when they’re kids, with ‘CO2 enrichment’.

            The first study is a terrifying portent, but the second is pretty scary too. Even if the acidification ‘push’ we are making to the marine ecosystem is beneficial to certain species, that is still inherently dangerous. How will such effects play out in the complex web of producer-predator relations?

            The law of unintended consequences has already reaped us a pretty bitter harvest. Why are some people so insistent that point to the unbroken vase, even as the room is shaking, and the roof looks like its about to cave-in on our heads?

  6. Fred Teal says:

    Joe,
    I know it is off topic but how can the current spate of tornadoes not be tied to climate change?

    • Tornado formation is extremely complex. Adding energy to the atmosphere can increase shearing winds which would actually suppress tornado formation. I expect most folks in the sciences will remain cautious on this one until they have at least a credible model connecting AGW with tornado formation. (I rather expect such models to be hitting the peer-review literature in earnest very shortly; if memory serves, a few have already begun to show up.)

  7. John Tucker says:

    Sea level rise/wetland accretion, ocean acidification, species adaption, invasive species and pathogens – all have some aspect of severity related to rate and are making the strong argument that ANY slowing of GG release is worthwhile.

    And its important NOW.

  8. Lou Grinzo says:

    There has been a parade of “it’s worse than we thought” discoveries in the last few years, from almost every corner of climate research, which get essentially zero news coverage outside of the places people here go for their news. Considering the implications, this OA story has to be one of the most extreme examples of that genre.

    But that’s OK — NBC’s 6:30 news broadcast didn’t cover this story but they found time to squeeze in a report on Rush Limbaugh’s latest foul pronouncements; that’s immeasurably more important than, you know, feeding the planet.

    • Peter says:

      Lou, the MSM is under strict orders of what to say and what not to say about AGW- and its deleterious effects- such as ocean acidification.

      Brian Williams and the rest are nothing but pieces of talking furniture. Ordered by the Media/Corporate trusts to suppress the truth. The Media is gambling the science is wrong, or the worst effects of climate change will be delayed- a miracle that seems like fantasy now.

    • Dick Smith says:

      Lou, I’ve agreed with you a lot. Not this time. Women’s ability to control reproduction is a critical link in population change. I’m grateful for every minute of coverage–and she’s one hell of a spokesperson.

  9. Leif says:

    How long a time span does that barren core of sediment that James Zachos is holding represent? What do you say GOBP, think you can hold out in your gated communities for this to blow over? Deniers? Inhofe? The dollars worth it to you?

  10. fj says:

    Hopefully, ongoing extremely dangerous climate brinkmanship won’t last much longer.

    This is the antithesis of advanced civilizations, education, intelligence, the rule of law and the supposed promise of humanity; rapidly in the process of blowing it big time; really big time.

    • Mark says:

      You are assuming we are “advanced”. What does that mean, exactly?

      When I was in gradeschool, one definition of human vs animal was that we use language and they don’t, which has since been disproven. Then it was tool use, which again has been disproven. So what is left to distinguish humans from “dumb animals”?

      Well, dumb animals reproduce until their population somewhat exceeds carrying capacity, and their population is reduced (via death) to achieve some sort of equilibrium. That’s what we are doing, and we won’t be any different than the “dumb animals” until we voluntarily limit our population to sustainability, before it is reduced via death. No species has yet demonstrated that group self-awareness in terms of ecological equilibrium. And that includes us. So are we really “advanced” or did we just take the termite stick tool and build on it ?

  11. Merrelyn Emery says:

    Given that the face of the planet is approx 70% water and probably the original home of all life, the current destruction of oceanic life has got to be the most devastating result of our last 200 years of disrespect for our home.

    And given that down here in SE Oz, we are currently drowning in water and still have days of rain to go, what is the impact of that extra 4% of water vapour in the atmosphere on the rate of acidification?

    All this excess water is ultimately making its way back into the oceans and hopefully diluting the acidification. Anybody done any modelling on this? Are these Aussie and other floods part of Gaia’s efforts to maintain stability? (no mysticism implied), ME

  12. Chris N says:

    It always amazes me that whenever a scientific paper like this is released and it is reviewed and presented in blogs and on the Internet, that all the non-scientific arm-chair experts come out of the woodwork and start the disputing process – citing spurious counter evidence and wild assertion, and even more disturbingly spiritual claptrap about mother nature and Gaia.

    Science teaches us to be skeptical – it’s the basis of scientific analysis and trying to establish theories, facts and “truth”.

    What science doesn’t do is impart emotional opinion – it is clinical. Whereas the arm-chair critics suffer from belief and fear – and emotion. What they post is opinion and surmising on their part.

    If you guys are going to argue about anthropogenic global warming, at least go study the subject so you know all of the science enough to be able to understand it and scientific process and method, before FORMING a conclusion about this topic.

    And if you had such knowledge you would be more inclined to say either, it is right, or that it isn’t convincing or conclusive, but not that it’s out and out wrong. The vast bulk of scientific papers being published on climate science attribute global warming and climate change trends to man – not volcanoes, sunspots, Gaia or sun cycles.

    Acidification of the ocean at the rate it is happening is UNPRECEDENTED. More research needs to be done to understand what is happening and how we might change the rate this is occurring.

  13. DBarr says:

    “Lalalalala, it’s only going to kill oysters and reefs and stuff, lalalalala. Not us humans, who need MORE oxygen than any other species.”

    The grandkids and grandparents are going first. It will be as though EVERYBODY has asthma.

    Folks ask me who we’ll sell our house on the beach to when the waters get too high.

    “Oh, that’s easy. We’ll just advertise to Republicans.”

  14. David Lewis says:

    The Royal Society published this alarming report on ocean acidification in 2005. The concluding sentence of their introduction stands up well today:

    “Ocean acidification is a powerful reason, in addition to that of climate change, for reducing global CO2 emissions. Action needs to be taken now to reduce global emissions of CO2 to the atmosphere to avoid the risk of irreversible damage to the oceans. We recommend that all possible approaches be considered to prevent CO2 reaching the atmosphere. No option that can make a significant contribution should be dismissed“.

    I’ve been studying the statements of scientists about CO2 and climate change for more than twenty years – i.e. I was calling on people to vote for a political party I was involved with in Canada as of 1988 on the basis that our primary goal would be stabilizing the composition of the atmosphere and attempting to return it to its pre-industrial composition. I can tell you there weren’t a lot of others in politics or in science who were doing the same thing.

    What jumped out at me immediately when I first started hearing about ocean acidification some years ago was how seriously the calls were for stabilizing the composition of the atmosphere at as low a level of CO2 as possible.

  15. xes says:

    bad, worse, the worst!

  16. Solar Jim says:

    It really is too bad, for life on earth, that unregulated crony militant state capitalism, or globalized corporatism, is built on the finance of precursors to carbonic acid, via the concept of “fossil fools” and ignition of lithospere matter (including weapons).

    Since private world market valuation of fossil substances are around ten trillion dollars, with sovereign “fossil reserves” at least doubling this perceived wealth, one might wish to prepare for a market adjustment like you wouldn’t believe.

    That is, if a supposedly intelligent civilization were to discover that three phases of mined matter are not “forms of energy.” All are actually precursors for ecologic death by numerous impacts of ecosperic acidification. They are necessarily stored matter, rather than “stored sunlight.”

    With abrupt climate change from critical human carbonic contamination, the planet’s response will be automatic. Then the results of a corrupted human experiment will be apparent. No Gaia will apply, only a contemporary grave site for the Sixth Extinction event in geologic time. Somehow we seem “dumber than dirt,” and probably are.