"When Coral Reefs Turn Brown"

Peter Mumby has an article today in the Guardian which discusses an underreported consequence of rising CO2 levels, namely, ocean acidification, which wrecks havoc with the the formation of calcium-based structure. Bye bye shrimp, lobster, and coral reefs.

An article in the New York Times, “Before It Disappears,” discusses “the tourism of doom,” for people who want to see natural sites they expect won’t be around for very long. Add coral reefs (at least healthy ones) to the list. The story also touches on one of my pet peeves, that so-called eco-tourism damages the environment:

Almost all these trips are marketed as environmentally aware and eco-sensitive — they are, after all, a grand tour of the devastating effects of global warming. But the travel industry, some environmentalists say, is preying on the frenzy. This kind of travel, they argue, is hardly green. It’s greedy, requiring airplanes and boats as well as new hotels.

Please, stay close to home and make a donation instead.

From the Guardian:

My mother used to tell me that drinking too much Coca-Cola was bad because it’ll ‘rot your teeth’. In fact, my first science experiment involved dissolving my baby teeth in a stagnant glass of Coke. Little did I know that this experiment would simulate one of the most serious consequences of global climate change on my favourite ecosystem – coral reefs!

Human beings have been burning fossil fuels for around 200 years, and the rate of increase in atmospheric CO2 is 100 times faster than has occurred in the past. Half of this CO2 has been absorbed into the surface layers of the ocean, making it increasingly acidic. This spells potential disaster for the thousands of animals in the oceans that create chalk skeletons. The list is a long one and includes many plankton species, lobsters, some of the prettiest sea shells, and corals. As water becomes more acidic, corals find it increasingly hard to extract calcium from the water and create calcium carbonate or chalk. Laboratory experiments have shown that a doubling of atmospheric CO2 beyond pre-industrial levels can lead to a 50% reduction in the growth rate of coral. But what does that really mean?

Corals have a very narrow environmental tolerance and are easily stressed if the temperature becomes too warm, or if the water becomes too murky. If growth becomes more energetically demanding, it is likely that corals will become far more susceptible to disease. The skeletons of corals will also become less dense (lighter) as growth rate declines and this means that corals are more likely to break apart when struck by hurricanes. All in all, the rise in ocean acidity as CO2 levels continue to increase, spells many acute problems for reefs – and this is a global problem.

Talking about ocean acidity is difficult because its effects are slow and largely invisible from day to day. However, rising acidity is not the only problem facing reefs as a result of climate change. In 1998, the world’s oceans became unusually warm, with average summer temperatures rising around 2C above normal. This doesn’t sound very impressive, but it killed vast areas of coral worldwide. This phenomenon is called coral bleaching and occurs because corals can only harness the sun’s energy for photosynthesis within a very narrow range of temperatures: if it becomes too warm, the corals effectively get ‘sunburn’. I witnessed these events around the globe, and was devastated to see some of the most beautiful reefs in the world (video) become transformed from a bewildering array of colour to a monotonous shade of brown. And all within three months. If the oceans continue to warm at the predicted rate, these coral bleaching events could occur every year within our lifetimes. This is a dire state of affairs when you consider that reefs can take more than a decade to recover from just a single bleaching event.

My concern is that the current trend of rising CO2 spells disaster for coral reefs and the many millions of people that depend on them for food, shelter from storms, and livelihoods. We must go further in reducing CO2 emissions and do everything possible to reduce the local insults to these systems from over-harvesting and pollution. Local action may buy vital time for the most diverse ecosystem on Earth.

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  1. dearieme

    We once had a choice of going on holiday to Venice or Dubrovnik (ancient Rugosa). We chose to see Venice “before it sank”. Venice is still there, Dubrovnik was devastated by Serbian artillery.

  2. Yves Smith


    By happenstance, I went to Dubrovnik this summer. It’s lovely and you should go if you have a chance. The locals have restored the city , although there are places where you can still see some shrapnel damage.

    They had big fires in the surrounding area this summer, so they really need the tourist dollars, and it isn’t as costly as other parts of Europe, which is an issue now with the Euro so high.

    But your general point well taken.

  3. Anonymous

    It is interesting how the Global Warming debate is moving. It was at one time clear that the problem was warming, and that it was caused by the polluting emission CO2, and that is why we should stop emitting it.

    Now, as the warming trend seems to be slowing, the ground station measurements appear dubious, and the satellite measurements show no trend, we are finding people refuse to talk about warming, instead they talk about climate change. CO2 is producing change, and that must be bad.

    Gradually, now, this is metamorphosing into a subtly different position, which is that CO2 is bad for reasons other than its effect on climate.

    It all reminds me of the man in Monty Python who was determined to give urine, in a blood donor clinic. We know that CO2 must be diminished. Now, lets, as Russell put it, find bad reasons for what we believe on instinct.

    I do not believe increased CO2 levels are the cause of the coral issue, and in fact, do not believe coral generally is crashing, though some reefs are and some are not. I am not convinced there is any very remarkable warming either. I am convinced there is warming, on about the scale of the Medieval warming. We need to get used to it, as there will be either more warming or cooling, whatever we do.

  4. Yves Smith

    Anon of 1:17 AM,

    I don’t know what your information sources are, but conferences of world experts on coral reefs disagree with opinions like yours and regard them as “delusionist”. It’s been known for some time that rising ocean temperatures and COS levels are major culprits in coral reef death (one of many illustrations). If you disagree once you have read the research, I suggest you take your argument up with the scientists.

    Similarly, I don’t know what your sources for your assertion “temperature increases are moderating” is either. The models prepared by the IPCC were out of date by the time their reports were prepared in the direction of understating, rather than overstating, temperature increases (here and here). The reports also failled to allow for the number of coal-fired electrical plants coming on line.. Arctic and Newfoundland ice is melting at a faster rate than anyone forecast in their models, another humbling surprise.

    I also happen to know people at the Explorers Club, which is chock a block with world class scientists, and non-partisan. Many of them spend a considerable amount of their time at locations where climate change can be seen, and many are either involved in or personally know scientists who are doing climate change related research. You don’t find climate change skeptics there.

  5. Mencius Moldbug

    The Explorers’ Club? Ah, the circles of power. I too notice that their opinions are remarkably accurate. At least, whenever they all agree. This magisterium is known as a “consensus,” and we regard it as pretty much infallible, like the Pope.

    (What puzzles me is that you don’t seem to attribute the same kind of omniscience, which must be simply just so right that it’s not even worth clicking a link to check, to econ departments. Or to the Fed.)

    I guess Edward Wegman doesn’t spend enough time over at the Explorers Club. Perhaps you were doing computational statistics, to quote the Beastie Boys, “when he was suckin’ his mutha’s dick.” In this case, there’s certainly no need to bother with his report!

  6. Yves Smith


    From Mr Wegman’s printed testimony in his 2006 presentation to Congress:

    “Because of this apparent isolation, we decided to attempt to understand the paleoclimate community by exploring the social network of authorships in temperature reconstruction.”

    “Because of these close connections, independent studies may not be as independent as they might appear on the surface. Although we have no direct data on the functioning of peer review within the paleoclimate community, but with 35 years of experience with peer review in both journals as well as evaluation of research proposals, peer review may not have been as independent as would generally be desirable.”

    “The MBH98/99 work has been sufficiently politicized that this community can hardly reassess their public positions without losing credibility.”

    –Now here, we have genuine exhibits of bad methodology and unsupported conjecture.

    Where did these non sequiturs come from, and who ordered them to be in there? In a report that begins by “circumscribing the substance” to “an independent verification by statisticians of the critiques of the statistical methodology…”?

    Anyway, as it was foretold, here it is: Our lobbied House Representatives are going after an old study that is already superseded, and they are ignoring all the other data. You scientists are being slandered, dissed, and dismissed.

    –Report by Lee A. Arnold, Society for the Long-Term Modeling of the Anti-Science Crooks in Congress, and Their “Social Network”

  7. Mencius Moldbug


    Did you read the McKitrick paper? Or Wegman’s original report? Or do you only read stuff written by authorities who agree with you? If you applied this methodology to finance, you’d get results that made Patrick Byrne and Jim Cramer look sane.

    The problem is very simple. It has nothing to do with Republicans or Democrats or whatever. McIntyre is a liberal. Wegman voted for Gore. He is not some kind of crazy AEI activist, he is the former chair of the NAS panel on statistics, who had never heard of any of this crap before Barton called him. Look at his CV – this is normal diligence for a statistician. Checking that people are using stats correctly is what a guy like Wegman does.

    No. The problem is money and power and fraud, pure and simple. I know you can’t believe your friends at the Explorers Club are mixed up in this kind of thing, but you have two eyes and a brain.

    Trillions of dollars are being reallocated on the basis of statistical work that would flunk a sophomore. And you’re not interested? What kind of skeptical antennae do you have?

    I don’t use the word fraud lightly. It is very clear that the people doing this work are aware of its dodginess. Mann ran all his calculations without the bristlecones and accidentally left them in a directory marked “CENSORED” on his FTP site. The man is a physicist. He knows what he’s doing.

    MBH99 is like a bad audit finding. When you find that Bear Stearns or Enron or Citicorp or whoever has fabricated some nonexistent asset on its books, you don’t give it a slap on the wrist and tell it to cross the line out. You unleash the forensic guys. You don’t find just one cockroach in a kitchen. And you don’t tell the health inspector, “sorry, we’ll kill it.”

    MBH99 is not an ancient, irrelevant result. It is the single most publicized piece of research in the history of IPCC climatology. It singlehandedly put Mann in Scientific American’s list of America’s 100 top young scientists. And it really is not a stretch to compare it to an ape jaw glued to a human skull. The thing reeks. It is data laundering of the worst kind.

    Sure, the “hockey team” has “moved on.” Despite the fact that the NAS panel chaired by North and the Wegman report, both of which concurred in all substantive opinions, both stated that further paleoclimate proxy studies should not use bristlecones or foxtails, we continue to see paleoclimate reconstructions full of them.

    And when IPCC climatologists are actually willing to use phrases like “if you want to make cherry pies, you have to be willing to pick cherries” (d’Arrigo) to committees investigating their work, we really have no reason to believe that their results are generated from their data and not the other way around. Actually, we have considerable reason to believe the opposite. “Why should I make the data available to you, when your aim is to try and find something wrong with it?” (Phil Jones.)

    (Unfortunately Climate Audit seems to be down at the moment. Google produced this source for the D’Arrigo quote.)

    The trouble is that the entire evidentiary case for AGW is nonreplicable and unfalsifiable. If you do not personally trust the researchers, you have no reason to trust the “science.”

    The first arm of the AGW case is paleoclimatology, which is trivially distorted by selection bias, ie, “good” results are published and not “bad” ones. The second is general circulation models or GCMs, which simulate the Earth’s atmosphere. GCMs are the product of tuning – they are certainly not derived directly from the laws of physics. See Nir Shaviv on the fine art of fitting elephants.

    If the IPCC community wanted my trust, they would have taken their own trash out, and censured Mann without the need to involve some freakin’ Republican from freakin’ Texas. Instead, they stonewalled and played defense. Well, if you want to live by bureaucratic hardball, you’ve got to be prepared to die by it.

    Because of this episode I judge the IPCC “consensus” the way I might judge the collective views of, say, the IMF. As a bunch of very smart people who nonetheless have a very clear institutional agenda. If you insist on taking them at face value, perhaps I could interest you in an Argentine bond or two.

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