Acidic oceans

The acidity of the ocean has increased by 30% since pre-industrial times and is predicted to double by 2100 because of increased uptake of CO2 according to expatriate Australian Australia’s leading oceanographer, Dr Tony Haymet, former Chief of Marine and Atmospheric Science at CSIRO, now director of the prestigious Scripps Institution of Oceanography and Vice Chancellor of Marine Sciences at the University of California.

Increasing the amount of CO2 in the oceans causes an increase in hydrogen carbonate ions, HCO3-, but a decrease in carbonate CO22- which organisms need to make calcium carbonate shells and other structures.

The predicted acidity increase will have unknown consequences for marine life and ecosystems such as coral reefs, tiny marine organisms called pteropods, and fish larvae to name but three. Each of these organisms plays a fundamental role in local ecosystems and the food web, therefore amplifying the effects of their forced changes.

“Unknown consequences” means we know it’s going to be bad, but not exactly how bad.

The pteropods are a critical species near the bottom of the food chain. If they are depleted we’ll have less fish to eat.

Acidity will inhibit the growth of corals, an adverse impact additional to coral bleaching.

55 million years ago when ocean acidity was much higher than today, shell-forming organisms vanished together with those higher in the food chain. But change is occurring faster now.

It is believed that the speed at which we are altering the current acidity of the ocean has not been seen before, and therefore we may not be able to anticipate the changes based on historical data.

Haymet believes that:

Ocean acidity, rather than temperature warming, may determine the upper limit of atmospheric CO2 that Earth can safely tolerate.

But even if emissions stopped today the acidification effect would continue for a century or more.

Roby Williams had an interesting chat with Joellen Russell of the University of Arizona recently about the increased uptake of CO2 in the Southern Ocean. It seems that the temperate storms, the low pressure systems, “the largest, strongest mean surface winds in the worldâ€? have moved south and intensified. This is causing direct mixing of sea and atmospheric gases to a depth of three kilometers with two effects.

Firstly, there is the same adverse impact on shell-forming organisms identified by Haymet.

Secondly, the additional uptake from the southerly movement of the winds is extraordinarily large, amounting to 20% of the ‘normal’ global uptake of CO2. That’s a lot of acid, but the good news is that global warming may be slowed by 20 to 40 years. Well, it’s not all that good, if, as Haymet suggests, the critical danger point may come from acidification of the oceans rather than temperature rise as such.

A final thought: When Haymet was out here for Rudd’s Climate Change Summit he told Kerry O’Brien that we were only 2% of the world’s innovation system and we should concentrate on things that we are good at. Although claiming he was misquoted by the SMH he was, I think, implying that ‘clean coal’ technology was not one of them.

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30 comments on “Acidic oceans
  1. Um, I think Haymet might be being a bit fatalistic on the possibility of Australia making a decent contribution to clean coal research. While money can’t achieve everything in science and technology, throwing enough of it at a problem generally results in interesting outcomes (if often not exactly what you were looking for in the first place).

    But maybe he knows something about the quality of research currently being done here on clean coal. I wonder anybody’s examined the research output of the various groups working on it recently?

  2. Brian says:

    It’s clear from what Haymet says that we are not even monitoring adequately what happens in the oceans. Hence his call for a Keeling Curve measure to mirror CO2 in the atmosphere. So maybe he’s touting for an extra bit of the funding pie.

    Still the role of coal is so huge that chucking a fair bit of money at the problem seems justified.

  3. Ken Miles says:

    HCO3-, but a decrease in carbonate CO22- which organisms need to make calcium carbonate shells and other structures.

    Minor error. Carbonate is CO32-, not CO22-.

  4. The other point to make is that acidifying oceans is almost as serious a problem as temperature rises. Even if the worst-case scenarios about global warming turn out to be overly pessimistic, wiping out much of the world’s marine life is just as disastrous.

  5. Graham Bell says:

    Thanks …. didn’t think anyone [apart from a few scientists] had noticed.

    So …. what can we individuals do to slow down the destruction?

  6. Graeme: same things you can do to slow down global warming: switch to gas or solar hot water (solar-electric is still worse than gas, by the way), switch to green power, insulate your home better, drive a more fuel-efficient car, drive less, possibly eat less meat (I’m not sure, but I think the arguments are pretty strong on this), don’t take overseas flights.

    However, individual action is almost certainly not going to get us to where we need to go.

  7. tim says:

    Now, I’m trying not to sound like a broken record, but in my defence, Brian actually raised it… 😉

    Haymet specifically told a former colleague of mine at the ALP climate love-in that geosequestration is deeply problematic and there are no timeline for when the technology may be ready. His position is that the science on climate change is in, but the science on geoseq is not.

    Thanks for raising the ocean acidification issue, Brian. It so rarely gets a look in.

  8. Brian says:

    Ken, maybe you could go and fix Wikipedia up. It’s all double-Dutch to me!

    tim, people like Hansen and Gore say that we have the science, but not the political will. Do you know whether Haymet disagrees with this? Both Hansen and Gore assume that geosequestration is going to work.

    Lovelock in ‘The Revenge of Gaia’ makes a big thing of the oceans. He and a mate ran a computer model which showed that algae, which thrives with a temperature of 10C, will be virtually wiped out when the CO2 levels reach 500ppm. Then the temperature jumps from a world average of 16C to 24C. As he says, it’s only a computer model, but perhaps worth a closer look!

  9. melaleuca says:

    In the United States, the National Oceanographic and Atmospheric Administration (NOAA), the National Science Foundation (NSF), and the U.S. Geological Survey (USGS) released a detailed report on oceanic acidification last year:

    As regards geosequestration, since 80% of the world’s fossil fuels are coal and much of this is in rapidly developing countries like India and China, it is immaterial what the finger-wagging do-gooders think; coal will be a major source of energy well into the future. Hence it is sensible and far-sighted on the part of the Federal Government to pour money into CO2 geosequestration research.

  10. Brian says:

    Thanks for the link, melaleuca. The report is for scientists, but the executive summary gives the overall story.

  11. tim says:

    Melaleuca, I am endlessly frustrated by this argument that because power now comes from coal, we automatically must continue to get power from coal into the future.

    Coal with geosequestration is not the same technology as coal. it is a radically new technology. It’s simply not that case that the transition from traditional coal to coal geoseq would be in any way simpler than the transition from traditional coal to renewables.

    Beautiful screen name, by the way, mismatching magnificently with your gravatar 😉

  12. tim says:

    Brian, Hansen has made comments to the effect that we may have to look for geosequestration options into the future, but he has been mostly careful to stay out of the debate on which solutions we should look to, being a climate scientist.

    However, he has made it very clear that we need to reduce emissions radically and very fast and, in this context, has pointed out that geoseq doesn’t meet that timeline.

    Gore. Well, much though I respect him for raising the profile of the issue, he has been very poor on the solutions indeed. Except to explicitly reject nukes.

  13. tim says:

    Re Lovelock and his 500ppm comment, Joe Romm has said that there is no such thing as stabilisation at 550ppm, since such a concentration would lead to melting of the tundra and other feedback loops that would take us to at least 700ppm, and consequently very great warming (and ocean acidity). That’s kind of the definition of ‘runaway climate change’.

    550ppm, I’d remind you, is what Stern reckons is OK. Well, he says 450ppm is safest, but that it’s politically unachievable. Ooops.

  14. Brian says:

    tim, I think you’ll find that Stern says 550 ppm CO2 equivalent, which is like saying 425ppm CO2.

    Publicly Stern said 60% by 2050 when he was here, but I’ve had a couple of hints that he was saying 90% in private briefings.

    Have you got a link for what you say about Hansen? Gotta go now, but tonight I’ll hunt up the link where he says we need to start dismantling traditional coal power stations from 2020 or 2025, and from memory he said we should build no new ones without geoseq after 2012.

    His ‘alternative scenario’ is quite explicit, to demonstrate that it’s not impossible.

  15. tim says:

    Yup, I’m talking CO2e, too, Brian.

    I’ll try to find the Hansen link.

  16. Brian says:

    Tim, the Hansen reference is here (large pdf). See slide 34.

    He says only geosequestered coal power stations after 2012 in the advanced economies and after 2022 in the developing world, with dirty stations to be bulldozed 2025-2050.

  17. trackback

    I pinched the link Melaleuca provided to the USA report on acidification too – very useful.

  18. tim says:

    Thanks for that Hansen piece, Brian.

    This position typifies the key problem with geoseq (other than the simple issue of it being wrong to produce a toxic waste when it is not necessary to do so…), and that is that the timeline is way out of whack.

    Even the International Coal Association, the global lobby group for big coal, has publicly accepted that that timeline is unrealistic and that no more than 10 commercial-scale coal with geoseq plants could be built anywhere in the world by 2020. See the ref here: news/Energy & Emissions/article19157-478.html

    [You can see the beginning of that story online, but have to subscribe to pointcarbon to see the whole thing. Worth doing, though, if you’re interested in these issues.]

    So, if the ICA are right, and if Ove Hoegh-Guldberg is also right and we need 80% cuts in the next 30 years, geoseq is simply going to be bypassed. We need to concentrate on the solutions that are here now – renewables and efficiency.

  19. Dany le roux says:

    Its a long time since I did any chemistry but I think that a genuine physical chemistry expert is needed on this blog to adjudicate the effect of increased CO2 in the oceans.
    I know that the bicarbonate ion HCO3- dissociates
    into CO3- – and H so that it does not necessarily follow that there will be a decrease in CO3- – ion with more dissolved CO2 .
    The situation is complicated by all the other stuff dissolved in the oceans and the buffer solutions it potentially creates.
    A 30% increase in acidity means a 30% increase in the H concentration which does not yet theoretically make the ocean acidic if the starting point is a pH bigger than 7.
    It may well be that more CO2 dissolved in the ocean drives the reaction toward producing more insoluble carbonate eg CaCO3( shells) and if that is the case then there is a potentially handy sink for any excess atmospheric CO2.
    What was the atmospheric concentration of CO2 when the White Cliffs of Dover were created?
    A chemistry expert is needed for this discussion.

  20. Dany le roux says:

    For some reason this comments facility would not print my ” ” after the “H”. I know that nowadays the hydroxonium ion is more fashionable than H plus but still I think I have made a point worth looking into.

  21. Dany le roux says:

    It is incapable of printing the plus sign which is what is meant to be between the ” “.

  22. Brian says:

    Dany le roux, I can’t help with Word Press software, I’m afraid.

    Nor with chemistry, which must be obvious. I can only hope that people like Haymet and those involved in the paper melaleuca linked to know their stuff – not an unreasonable expectation, but sometimes you are let down.

    Speaking of which, tim, it wouldn’t surprise if Hansen knows nothing much about power stations. But you’d think someone would tell him and he’d listen. He often proclaims his absolute passion about adhering to the science.

  23. tim says:

    Brian, yes indeed, Hansen should know at least a fair bit about the technological options. And I assume he does. The way I read it, he is calling for a moratorium from that date until the technology is available.

  24. Brian says:

    tim, Hansen was saying much the same thing at least from a Scientific American article in 2003 (pdf) without being specific about the time-lined with respect to Power stations. The urgent 10-year time frame just kept moving forward like a carrot on a stick. Now 4 years down the track he’d still say we haven’t committed.

    In that piece he said:

    International cooperation on coal use and sequestration is probably the most important action needed to stabilize atmospheric composition and climate.

    You are saying we need to bypass coal CO2 sequestration. I’m thinking you could be right.

    Bob Brown keeps saying we can save 30% of current energy usage but I’ve never seen any detail on how this might be done. Have you?

  25. tim says:

    Brian, so pleased you’re thinking I may be right on bypassing coal with geoseq!

    Re the 30% energy savings, I can only assume that Brown is referring to the COAG paper from a few years ago, Towards a National Framework on Energy Efficiency. That excellent study demonstrated that we could cut energy use across all sectors of the Australian economy by up to 30% immediately, using off the shelf technologies with a payback of 4 years.

    Again, I am happy to forward a copy of that paper that I have on my hard drive. You may be able to find it by googling, too.

  26. Brian says:

    Found the executive summary (pdf). It might do for now, but is there more?

  27. Dany le roux says:

    I have since done a bit of reading on the subject of ocean acidity and in particular the pdf “Ocean acidification due to increasing atmospheric carbon dioxide.”
    Ocean chemistry is a very complex matter with many unknowns and I think my main concern is that in this document and in the Haymet MSN article there is speculation presented as factoid eg( from Haymet):

    � Take for example the pteropod, a free-swimming snail that lives near the surface of the ocean. It is a key food source for a number of fish and marine mammals. As ocean acidity rises, pteropods experience a double threat. Not only does the water corrode their shells, it may inhibit their ability to build shells in the first place, leaving them without an adequate protective layer.�

    By and large ocean scientists do not know the consequences of increased ocean acidity due to increased atmospheric CO2 and Haymet even says so:

    “We also call for a determination of the biological consequences of increasing ocean acidity and its effects on the ocean food web.â€?

    Instead of saying that the pH of the oceans has been estimated to have decreased from 8.25 to 8.14 (which looks unimpressive to the uninitiated because it is the negative of a log scale ) he uses the big figure of 30% and has promoted it from estimation to fact :

    “We have already experienced an increase in ocean acidity of nearly 30 percent compared to pre-industrial times and a doubling has been predicted by 2100.â€?

    What I am saying is that these guys are asking for research money because they do not know what is going on and the language they use reflects this uncertainty .They should be given the money and asked to report back without hype.

  28. Brian says:

    Dany, that’s really helpful.

    I can forgive Haymet for turning a log scale story into simple perentages, given his audience.

    Tim that paper I found was of course only a submission.

    I’ve found some stuff from the NFEE site.

    Gotta go now.

  29. Brian says:

    Problem solved. The paper tim was referring to was Towards a National Framework for Energy Efficiency – Issues and Challenges: Discussion Paper which can be downloaded from here.

    It does seem as though there is significant scope for energy savings.

    Dany, would I be right in saying that the title ‘Acidic oceans’ is misleading, in that the oceans will always be alkaline and we should really talk about them becoming less alkaline rather than more acidic?

  30. Dany le roux says:

    Brian,chemically speaking the pH and the pOH add up to 14 in a solution.The pH is the concentration of hydrogen ions and as this figure goes down the concentration of H ions goes up and the solution becomes more acidic or if you want, less alkaline.A pH of 7 with a pOH of 7 is a neutral solution.Wikipedia says the ocean pH is now 8.14 (average) which is definitely alkaline. Try Googling pH for an explanation of “p”.
    My point was that Haymet and the people in the other paper I mentioned(Ocean Acidification Due to the Increasing Atmospheric CO2) seem to think that hyperbole is the best way to get the attention of those with the research money purse strings.If atmospheric CO2 goes up and does bad things to the extra-oceanic climate then it should follow that what happens in the oceans becomes very important as well.In the paper “OADTTIA CO2” they talk about the effect too much acidity will have on the tourist trade for God’s sake among other negative things.They were very short of discussion of what happens at great ocean depths and big on the ecology and chemistry of the shallow ocean environment (where all the SCUBA and fishing activity happens).
    I mentioned with my shakey chemistry the possibility that the oceans could provide a sink for CO2 and to some extent mitigate the effect of increased atmospheric CO2.In other words there is scope for ocean research to reveal an optimistic prognosis for the health of the atmosphere but these research money seekers have decided to push the fear button instead because this approach worked to make people aware of global warming.
    If I were a politician this short time out from an election I would be inclined to focus attention on the possibility of positive climate outcomes associated with the oceans and promise research money accordingly.

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