Monday, March 21, 2011

Tamino is watching the food

Open Mind takes on what I have argued is the critical "final common pathway" of global warming risks -- crop and supply chain failures (which may start small, and end up big) leading to a situation in which -- there's no way to say this gently -- people will starve.

It's hard for us to imagine that society to break down in that way -- for people in the developed world, their only experience of food is as something they get in exchange for money. That we could have money and not be able to buy the things we need is so far out of our experience that it may seem preposterous. It's not. It's closer to such as us than we like to think.

Tamino rocks the graphs to analyze the cause of the recent explosive spike in food prices:

Money quote:

The 2010-2011 rise in food prices was triggered by a rise in cereals prices. It started in July of 2010, and still hasn’t relented. Sure, there are other factors too — and as usually happens, an increase in cereals prices can cause a “ripple effect,” leading to increased prices in other commodities. But the root cause is something that happened to cereals prices in July of 2010.

And what on earth could that be?

“Cereals” includes wheat. What if one of the world’s largest wheat producers had devastating crop losses, reducing their production by a third? What if they were one of the world’s biggest wheat exporters, but production was so reduced that their exports dropped to zero? That’s exactly what happened in Russia. And the trouble started in July of 2010.

Why did the Russian wheat harvest suffer so? Because of the record-breaking heat wave and drought which plagued a massive region, at just the wrong time for Russian agriculture. And one of the contributing factors is: global warming.

That’s the ugly, deadly dangerous secret the denialists don’t want you to think about. That’s why they sank so low as to try to blame inflation of food prices on attempts to fight global warming, when it’s really due to: global warming.

All I can add to Tamino's analysis is this: we live in a highly complex and interrelated civilization, and I'm a fan. I wouldn't want to be a hunter-gatherer. Art, science, literature, philosophy and engineering all cease to exist without the specialization that has increasingly characterized human societies since the adoption of settled agriculture. But specialization comes with a price. A more complex machine is more prone to failure and more difficult to repair.

Picture two wells. When you replace a well that is a hole in ground, a bucket, and a rope with a diesel generator, water pump, and a set of pipes, you improve the functionality of that well immensely, but you also add many, many more points of failure. Similarly, as our society becomes more and more sophisticated, greater caution is called for, more redundancy, more effort to anticipate problems, more humility. Yet the wealth and comfort we enjoy engenders the opposite attitude -- we have developed an exaggerated idea of our power over nature, come to take our technology for granted, developed an expectation of a constant increase in prosperity which may be possible, but is not inevitable by any means.

We are drawing the wrong lessons from the explosive change that the scientific method and the rule of law have brought us over the last 250 years. I very much fear that there is a rude awakening ahead.

Saturday, March 19, 2011

People having a bad day: Muammar Gaddafi and Anthony Watts

For those not following the news from Libya, Gaddafi's foreign mercenaries have been rolling over poorly-equipped and mostly untrained rebels. Yesterday, however, the UN approved a no-fly zone and Britain, France, and the United States all declared their intention to pound the snot out of Gaddafi's forces.

This has, of course, provoked more invective and threatening from the Libyan dictator, but Gaddafi is smart; faced with the bully's nightmare, somebody bigger and stronger coming down on him, with him as little able to resist as the people he has been bullying, he declared a cease-fire and played for time.

Watts is not so wise. Google has struck fear in his heart, and so he has unleashed a Gaddafiesque rant, making not an iota of rational sense, but expressing the same fears -- nobody bigger and stronger better get between him and his lunch money racket. So he has unleashed his most moronic acolyte, Willis Eschenbach, to proclaim:


My goodness, how dare they . . . what, exactly?, the technology giant's philanthropic arm, has hand-picked a team of 21 fellows working in climate research to improve the way the science of global warming is communicated to the public and lawmakers through new media.

So it is not Google's search engine, but a raindrop of the money made off the search engine, which is going into this effort. It is not policy advocacy, but rather an effort to improve science communication. They did not chose sides in a scientific debate, they chose scientists over non-scientists like Willis who mistakenly believe that they are engaged in a scientific debate.

Nobody, not even the late and lamented Steve Goddard, can compete with Willis is sheer fallacy density, which is no doubt why Anthony picked him for this assignment, pitching "An Open Letter to Google" in which he drops the bombshell that he doesn't trust Google any more:

In fact, that’s why up until now I trusted Google, because I always felt that I was being given the unvarnished truth. I always felt that Google could be trusted, because you didn’t have a dog in the fight.

Willis thinks Google searches return only "the unvarnished truth." That certainly explains some of his odder opinions.

Seriously, though, what is going on here? Well, they're scared. They're scared, because Watts measures his importance according to the only metric by which he is successful; his presence on the internet:

No other climate related blog has a 50 million hit number. Some, like Joe Romm try to claim the numbers don’t matter, or try to claim that some other number matters more. But (and it’s a big one) he doesn’t show his own number counter.

Watts uses this internet presence to bully others, from threatening commenters he doesn't like with letters to their workplaces, to slandering other bloggers, to attacking people with his readers, as he did when he urged them to visit Discovery blogs and "shout them down."

Google's tiny project to improve science communication scares Watts because in his imagination, he has transformed web traffic into the be-all and end-all of significance. It's not degrees, scientific expertise, or other accomplishments, it's not business success, political office, or general respect of the public. It's not, needless to say, a reputation for honesty or integrity. Watts is a giant zero according to all those conventional metrics. Page traffic is the one thing he can point to.

So it's not hard to see why Google taking notice of climate science is as disturbing to Watts as the warplanes of the Sixth Fleet are to Gaddafi. Because if the measure of a man is his page views, who gets more page views than anyone?

Wednesday, March 9, 2011

A thousand cuts

NYT: "Heat Slashes Colombian Crop, and Coffee Drinkers Pay the Price"

Money quote:

But over the last few years, coffee yields have plummeted here and in many of Latin America’s other premier coffee regions as a result of rising temperatures and more intense and unpredictable rains, phenomena that many scientists link partly to global warming.

Want to picture the headlines of the future? For "coffee" substitute wheat. Or rice. Or corn. And for "coffee drinkers" substitute "human civilization."

Sunday, March 6, 2011

Idiot comment of the day

From the moronopolis:

John Marshall says:
March 1, 2011 at 6:18 am

Indonesia is a developing country so this begs the question WHY. Any reduction of CO2 output will reduce already poor people to total poverty and death. Development needs CO2 output in extra energy production.
Why do the alarmists keep going on about deforestation? NASA research has shown that within ten years rainforest regrows to such an extent as to be unrecognizable from space compared to untouched forest. When rainforests are looked at, compared with forest total age and tree lifetime then many tens of tree generations have passed compared to total forest age. Trees die and their seeds grow. It is important that the local people get some income from the forest to pull them out of poverty.
Get Real.

Wow, I had no idea things were this bad: ANY reduction of Co2 emissions (solar panels, wind farms, fuel-efficient cooking stoves, LED lights?) will not only make poor people, like, totally poor (for reals) but actually kill them. At which point the poverty would not be so much of a problem, one might think. Totally.

Friday, March 4, 2011

Accelerating CO2 Trend

h/t CO2 Now

Decade                 Total Increase        Annual Rate of Increase

2001 –  2010              20.38 ppm                     2.04 ppm per year 

1991 –  2000               15.24 ppm                     1.52 ppm per year 

1981 –  1990                15.48 ppm                     1.55 ppm per year 

1971 –  1980               13.00 ppm                     1.30 ppm per year 

1961 –  1970                 8.77 ppm                     0.88 ppm per year 



Annual CO2 Data:  Scripps / NOAA data for atmospheric CO2*    

*Calculations are made by using annual data (Mauna Loa Observatory). 

Wednesday, March 2, 2011

New addition to blog list: AGWobserver

Just discovered an exceptional resource for tracking the most interesting papers on climate change: AGWobserver (h/t Michael Tobis). There is a lot there for people of every viewpoint and every level of technical literacy.

Seeing so much of the literature gathered in one place is a reminder of how ridiculous the psuedoskeptics' elitist/ivory tower conceit -- that climate scientists are a small group of impractical theorists holed up in their offices, making wild inferences from computer models -- really is. Climate scientists are in the world, collecting vast amounts of data coming out of many disciplines -- marine biology, chemistry, atmospheric physics, dendrochronology and many, many more. Anthropogenic climate change is not "just" a theory, it is the only theory that can begin to account for the vast array of evidence of a warming world.

It's been said before, but it bears repeating: this is not just about the temperature record, or the ice cover at the poles, or the rate of glacier retreat (all arguments which the "skeptics" have lost, over and over again). There are dozens of independent lines of evidence. Take coral reefs. Have the ivory tower scientists noticed any changes in coral reefs which might be indicative of a warming world? Is anybody looking at this, or are the bumbling, rent-seeking conspirator-scientists just making wild inferences from their beloved computer models?

Well, there's been a little research:

Rapid poleward range expansion of tropical reef corals in response to rising sea surface temperatures – Yamano et al. (2011) “Rising temperatures caused by climatic warming may cause poleward range shifts and/or expansions in species distribution. Tropical reef corals (hereafter corals) are some of the world’s most important species, being not only primary producers, but also habitat-forming species, and thus fundamental ecosystem modification is expected according to changes in their distribution. Although most studies of climate change effects on corals have focused on temperature-induced coral bleaching in tropical areas, poleward range shifts and/or expansions may also occur in temperate areas. We show the first large-scale evidence of the poleward range expansion of modern corals, based on 80 years of national records from the temperate areas of Japan, where century-long measurements of in situ sea-surface temperatures have shown statistically significant rises. Four major coral species categories, including two key species for reef formation in tropical areas, showed poleward range expansions since the 1930s, whereas no species demonstrated southward range shrinkage or local extinction. The speed of these expansions reached up to 14 km/year, which is far greater than that for other species. Our results, in combination with recent findings suggesting range expansions of tropical coral-reef associated organisms, strongly suggest that rapid, fundamental modifications of temperate coastal ecosystems could be in progress.” Yamano, H., K. Sugihara, and K. Nomura (2011), Geophys. Res. Lett., 38, L04601, doi:10.1029/2010GL046474.

Modeling regional coral reef responses to global warming and changes in ocean chemistry: Caribbean case study – Buddemeier et al. (2011) “Climatic change threatens the future of coral reefs in the Caribbean and the important ecosystem services they provide. We used a simulation model [Combo (“COral Mortality and Bleaching Output”)] to estimate future coral cover in the part of the eastern Caribbean impacted by a massive coral bleaching event in 2005. Combo calculates impacts of future climate change on coral reefs by combining impacts from long-term changes in average sea surface temperature (SST) and ocean acidification with impacts from episodic high temperature mortality (bleaching) events. We used mortality and heat dose data from the 2005 bleaching event to select historic temperature datasets, to use as a baseline for running Combo under different future climate scenarios and sets of assumptions. Results suggest a bleak future for coral reefs in the eastern Caribbean. For three different emissions scenarios from the Intergovernmental Panel on Climate Change (IPCC; B1, A1B, and A1FI), coral cover on most Caribbean reefs is projected to drop below 5% by the year 2035, if future mortality rates are equivalent to some of those observed in the 2005 event (50%). For a scenario where corals gain an additional 1–1.5°C of heat tolerance through a shift in the algae that live in the coral tissue, coral cover above 5% is prolonged until 2065. Additional impacts such as storms or anthropogenic damage could result in declines in coral cover even faster than those projected here. These results suggest the need to identify and preserve the locations that are likely to have a higher resiliency to bleaching to save as many remnant populations of corals as possible in the face of projected wide-spread coral loss.” R. W. Buddemeier, Diana R. Lane and J. A. Martinich, Climatic Change, DOI: 10.1007/s10584-011-0022-z. [full text]

Coral reefs may start dissolving when atmospheric CO2 doubles – Silverman et al. (2009) “Calcification rates in stony corals are expected to decline significantly in the near future due to ocean acidification. In this study we provide a global estimate of the decline in calcification of coral reefs as a result of increase in sea surface temperature and partial pressure of CO2. This estimate, unlike previously reported estimates, is based on an empirical rate law developed from field observations for gross community calcification as a function of aragonite degree of saturation (Ωarag), sea surface temperature and live coral cover. Calcification rates were calculated for more than 9,000 reef locations using model values of Ωarag and sea surface temperature at different levels of atmospheric CO2. The maps we produced show that by the time atmospheric partial pressure of CO2 will reach 560 ppm all coral reefs will cease to grow and start to dissolve.” Silverman, J., B. Lazar, L. Cao, K. Caldeira, and J. Erez (2009), Geophys. Res. Lett., 36, L05606, doi:10.1029/2008GL036282. [full text]

Climate change and coral reef bleaching: An ecological assessment of long-term impacts, recovery trends and future outlook – Baker et al. (2008) “Since the early 1980s, episodes of coral reef bleaching and mortality, due primarily to climate-induced ocean warming, have occurred almost annually in one or more of the world’s tropical or subtropical seas. Bleaching is episodic, with the most severe events typically accompanying coupled ocean–atmosphere phenomena, such as the El Niño-Southern Oscillation (ENSO), which result in sustained regional elevations of ocean temperature. Using this extended dataset (25+ years), we review the short- and long-term ecological impacts of coral bleaching on reef ecosystems, and quantitatively synthesize recovery data worldwide. Bleaching episodes have resulted in catastrophic loss of coral cover in some locations, and have changed coral community structure in many others, with a potentially critical influence on the maintenance of biodiversity in the marine tropics. Bleaching has also set the stage for other declines in reef health, such as increases in coral diseases, the breakdown of reef framework by bioeroders, and the loss of critical habitat for associated reef fishes and other biota. Secondary ecological effects, such as the concentration of predators on remnant surviving coral populations, have also accelerated the pace of decline in some areas. Although bleaching severity and recovery have been variable across all spatial scales, some reefs have experienced relatively rapid recovery from severe bleaching impacts. There has been a significant overall recovery of coral cover in the Indian Ocean, where many reefs were devastated by a single large bleaching event in 1998. In contrast, coral cover on western Atlantic reefs has generally continued to decline in response to multiple smaller bleaching events and a diverse set of chronic secondary stressors. No clear trends are apparent in the eastern Pacific, the central-southern-western Pacific or the Arabian Gulf, where some reefs are recovering and others are not. The majority of survivors and new recruits on regenerating and recovering coral reefs have originated from broadcast spawning taxa with a potential for asexual growth, relatively long distance dispersal, successful settlement, rapid growth and a capacity for framework construction. Whether or not affected reefs can continue to function as before will depend on: (1) how much coral cover is lost, and which species are locally extirpated; (2) the ability of remnant and recovering coral communities to adapt or acclimatize to higher temperatures and other climatic factors such as reductions in aragonite saturation state; (3) the changing balance between reef accumulation and bioerosion; and (4) our ability to maintain ecosystem resilience by restoring healthy levels of herbivory, macroalgal cover, and coral recruitment. Bleaching disturbances are likely to become a chronic stress in many reef areas in the coming decades, and coral communities, if they cannot recover quickly enough, are likely to be reduced to their most hardy or adaptable constituents. Some degraded reefs may already be approaching this ecological asymptote, although to date there have not been any global extinctions of individual coral species as a result of bleaching events. Since human populations inhabiting tropical coastal areas derive great value from coral reefs, the degradation of these ecosystems as a result of coral bleaching and its associated impacts is of considerable societal, as well as biological concern. Coral reef conservation strategies now recognize climate change as a principal threat, and are engaged in efforts to allocate conservation activity according to geographic-, taxonomic-, and habitat-specific priorities to maximize coral reef survival. Efforts to forecast and monitor bleaching, involving both remote sensed observations and coupled ocean–atmosphere climate models, are also underway. In addition to these efforts, attempts to minimize and mitigate bleaching impacts on reefs are immediately required. If significant reductions in greenhouse gas emissions can be achieved within the next two to three decades, maximizing coral survivorship during this time may be critical to ensuring healthy reefs can recover in the long term.” Andrew C. Baker, Peter W. Glynn, and Bernhard Riegl, Estuarine, Coastal and Shelf Science, Volume 80, Issue 4, 10 December 2008, Pages 435-471, doi:10.1016/j.ecss.2008.09.003. [full text]

Coral Reefs Under Rapid Climate Change and Ocean Acidification – Hoegh-Guldberg et al. (2007) “Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2°C by 2050 to 2100, values that significantly exceed those of at least the past 420,000 years during which most extant marine organisms evolved. Under conditions expected in the 21st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems. The result will be less diverse reef communities and carbonate reef structures that fail to be maintained. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reefs increasingly toward the tipping point for functional collapse. This review presents future scenarios for coral reefs that predict increasingly serious consequences for reef-associated fisheries, tourism, coastal protection, and people. As the International Year of the Reef 2008 begins, scaled-up management intervention and decisive action on global emissions are required if the loss of coral-dominated ecosystems is to be avoided.” O. Hoegh-Guldberg, P. J. Mumby, A. J. Hooten, R. S. Steneck, P. Greenfield, E. Gomez, C. D. Harvell, P. F. Sale, A. J. Edwards, K. Caldeira, N. Knowlton, C. M. Eakin, R. Iglesias-Prieto, N. Muthiga, R. H. Bradbury, A. Dubi and M. E. Hatziolos, Science 14 December 2007: Vol. 318 no. 5857 pp. 1737-1742, DOI: 10.1126/science.1152509. [full text]

Effects of climate and seawater temperature variation on coral bleaching and mortality – McClanahan et al. (2007) “Coral bleaching due to thermal and environmental stress threatens coral reefs and possibly people who rely on their resources. Here we explore patterns of coral bleaching and mortality in East Africa in 1998 and 2005 in a region where the equatorial current and the island effect of Madagascar interact to create different thermal and physicochemical environments. A variety of temperature statistics were calculated, and their relationships with the degree-heating months (DHM), a good predictor of coral bleaching, determined. Changes in coral cover were analyzed from 29 sites that span >1000 km of coastline from Kenya to the Comoros Islands. Temperature patterns are influenced by the island effect, and there are three main temperature environments based on the rise in temperature over 52 years, measures of temperature variation, and DHM. Offshore sites north of Madagascar that included the Comoros had low temperature rises, low DHM, high standard deviations (SD), and the lowest relative coral mortality. Coastal sites in Kenya had moderate temperature rises, the lowest temperature SD, high DHM, and the highest relative coral mortality. Coastal sites in the south had the highest temperature rises, moderate SD and DHM, and low relative coral mortality. Consequently, the rate of temperature rise was less important than background variation, as reflected by SD and kurtosis measures of sea surface water temperature (SST), in predicting coral survival across 1998. Coral bleaching responses to a warm-water anomaly in 2005 were also negatively related to temperature variation, but positively correlated with the speed of water flow. Separating these effects is difficult; however, both factors will be associated with current environments on the opposite sides of reefs and islands. Reefs in current shadows may represent refugia where corals acclimate and adapt to environmental variation, which better prepares them for rising temperature and anomalies, even though these sites are likely to experience the fastest rates of temperature rise. We suggest that these sites are a conservation priority and should be targeted for management and further ecological research in order to understand acclimation, adaptation, and resilience to climate change.” McClanahan, Timothy R., Mebrahtu Ateweberhan, Christopher A. Muhando, Joseph Maina, and Mohammed S. Mohammed. 2007, Ecological Monographs 77:503–525, doi:10.1890/06-1182.1. [full text]

The role of zooxanthellae in the thermal tolerance of corals: a ‘nugget of hope’ for coral reefs in an era of climate change – Berkelmans & van Oppen (2006) “The ability of coral reefs to survive the projected increases in temperature due to global warming will depend largely on the ability of corals to adapt or acclimatize to increased temperature extremes over the next few decades. Many coral species are highly sensitive to temperature stress and the number of stress (bleaching) episodes has increased in recent decades. We investigated the acclimatization potential of Acropora millepora, a common and widespread Indo-Pacific hard coral species, through transplantation and experimental manipulation. We show that adult corals, at least in some circumstances, are capable of acquiring increased thermal tolerance and that the increased tolerance is a direct result of a change in the symbiont type dominating their tissues from Symbiodinium type C to D. Our data suggest that the change in symbiont type in our experiment was due to a shuffling of existing types already present in coral tissues, not through exogenous uptake from the environment. The level of increased tolerance gained by the corals changing their dominant symbiont type to D (the most thermally resistant type known) is around 1–1.5 °C. This is the first study to show that thermal acclimatization is causally related to symbiont type and provides new insight into the ecological advantage of corals harbouring mixed algal populations. While this increase is of huge ecological significance for many coral species, in the absence of other mechanisms of thermal acclimatization/adaptation, it may not be sufficient to survive climate change under predicted sea surface temperature scenarios over the next 100 years. However, it may be enough to ‘buy time’ while greenhouse reduction measures are put in place.” Ray Berkelmans and Madeleine J.H van Oppen, Proc. R. Soc. B 22 September 2006 vol. 273 no. 1599 2305-2312, doi: 10.1098/rspb.2006.3567. [full text]

Global assessment of coral bleaching and required rates of adaptation under climate change – Donner et al. (2005) “Elevated ocean temperatures can cause coral bleaching, the loss of colour from reef-building corals because of a breakdown of the symbiosis with the dinoflagellate Symbiodinium. Recent studies have warned that global climate change could increase the frequency of coral bleaching and threaten the long-term viability of coral reefs. These assertions are based on projecting the coarse output from atmosphere–ocean general circulation models (GCMs) to the local conditions around representative coral reefs. Here, we conduct the first comprehensive global assessment of coral bleaching under climate change by adapting the NOAA Coral Reef Watch bleaching prediction method to the output of a low- and high-climate sensitivity GCM. First, we develop and test algorithms for predicting mass coral bleaching with GCM-resolution sea surface temperatures for thousands of coral reefs, using a global coral reef map and 1985–2002 bleaching prediction data. We then use the algorithms to determine the frequency of coral bleaching and required thermal adaptation by corals and their endosymbionts under two different emissions scenarios. The results indicate that bleaching could become an annual or biannual event for the vast majority of the world’s coral reefs in the next 30–50 years without an increase in thermal tolerance of 0.2–1.0°C per decade. The geographic variability in required thermal adaptation found in each model and emissions scenario suggests that coral reefs in some regions, like Micronesia and western Polynesia, may be particularly vulnerable to climate change. Advances in modelling and monitoring will refine the forecast for individual reefs, but this assessment concludes that the global prognosis is unlikely to change without an accelerated effort to stabilize atmospheric greenhouse gas concentrations.” Simon D. Donner, William J. Skirving, Christopher M. Little, Michael Oppenheimer, Ove Hoegh-Guldberg, Global Change Biology, Volume 11, Issue 12, pages 2251–2265, December 2005. [full text]

Coral reefs: Corals’ adaptive response to climate change – Baker et al. (2004) “The long-term response of coral reefs to climate change depends on the ability of reef-building coral symbioses to adapt or acclimatize to warmer temperatures, but there has been no direct evidence that such a response can occur. Here we show that corals containing unusual algal symbionts that are thermally tolerant and commonly associated with high-temperature environments are much more abundant on reefs that have been severely affected by recent climate change. This adaptive shift in symbiont communities indicates that these devastated reefs could be more resistant to future thermal stress, resulting in significantly longer extinction times for surviving corals than had been previously assumed.” Andrew C. Baker, Craig J. Starger, Tim R. McClanahan & Peter W. Glynn, Nature 430, 741 (12 August 2004) | doi:10.1038/430741a. [full text]

Coral reef calcification and climate change: The effect of ocean warming – McNeil et al. (2004) “Coral reefs are constructed of calcium carbonate (CaCO3). Deposition of CaCO3 (calcification) by corals and other reef organisms is controlled by the saturation state of CaCO3 in seawater (Ω) and sea surface temperature (SST). Previous studies have neglected the effects of ocean warming in predicting future coral reef calcification rates. In this study we take into account both these effects by combining empirical relationships between coral calcification rate and Ω and SST with output from a climate model to predict changes in coral reef calcification rates. Our analysis suggests that annual average coral reef calcification rate will increase with future ocean warming and eventually exceed pre-industrial rates by about 35% by 2100. Our results suggest that present coral reef calcification rates are equivalent to levels in the late 19th century and does not support previous suggestions of large and potentially catastrophic decreases in the future.” McNeil, B. I., R. J. Matear, and D. J. Barnes (2004), Geophys. Res. Lett., 31, L22309, doi:10.1029/2004GL021541. [full text, comment by Kleypas et al., reply by McNeil et al.]

Global Trajectories of the Long-Term Decline of Coral Reef Ecosystems – Pandolfi et al. (2003) “Degradation of coral reef ecosystems began centuries ago, but there is no global summary of the magnitude of change. We compiled records, extending back thousands of years, of the status and trends of seven major guilds of carnivores, herbivores, and architectural species from 14 regions. Large animals declined before small animals and architectural species, and Atlantic reefs declined before reefs in the Red Sea and Australia, but the trajectories of decline were markedly similar worldwide. All reefs were substantially degraded long before outbreaks of coral disease and bleaching. Regardless of these new threats, reefs will not survive without immediate protection from human exploitation over large spatial scales.” John M. Pandolfi, Roger H. Bradbury, Enric Sala, Terence P. Hughes, Karen A. Bjorndal, Richard G. Cooke, Deborah McArdle, Loren McClenachan, Marah J. H. Newman, Gustavo Paredes, Robert R. Warner and Jeremy B. C. Jackson, Science 15 August 2003: Vol. 301 no. 5635 pp. 955-958, DOI: 10.1126/science.1085706.

Climate Change, Human Impacts, and the Resilience of Coral Reefs – Hughes et al. (2003) “The diversity, frequency, and scale of human impacts on coral reefs are increasing to the extent that reefs are threatened globally. Projected increases in carbon dioxide and temperature over the next 50 years exceed the conditions under which coral reefs have flourished over the past half-million years. However, reefs will change rather than disappear entirely, with some species already showing far greater tolerance to climate change and coral bleaching than others. International integration of management strategies that support reef resilience need to be vigorously implemented, and complemented by strong policy decisions to reduce the rate of global warming.” T. P. Hughes, A. H. Baird, D. R. Bellwood, M. Card, S. R. Connolly, C. Folke, R. Grosberg, O. Hoegh-Guldberg, J. B. C. Jackson, J. Kleypas, J. M. Lough, P. Marshall, M. Nyström, S. R. Palumbi, J. M. Pandolfi, B. Rosen and J. Roughgarden, Science 15 August 2003: Vol. 301 no. 5635 pp. 929-933, DOI: 10.1126/science.1085046. [full text]

Microbial diseases of corals and global warming – Rosenberg & Haim (2002) “Coral bleaching and other diseases of corals have increased dramatically during the last few decades. As outbreaks of these diseases are highly correlated with increased sea-water temperature, one of the consequences of global warming will probably be mass destruction of coral reefs. The causative agent(s) of a few of these diseases have been reported: bleaching of Oculina patagonica by Vibrio shiloi; black band disease by a microbial consortium; sea-fan disease (aspergillosis) by Aspergillus sydowii; and coral white plague possibly by Sphingomonas sp. In addition, we have recently discovered that Vibrio coralyticus is the aetiological agent for bleaching the coral Pocillopora damicornis in the Red Sea. In the case of coral bleaching by V. shiloi, the major effect of increasing temperature is the expression of virulence genes by the pathogen. At high summer sea-water temperatures, V. shiloi produces an adhesin that allows it to adhere to a β-galactoside-containing receptor in the coral mucus, penetrate into the coral epidermis, multiply intracellularly, differentiate into a viable-but-not-culturable (VBNC) state and produce toxins that inhibit photosynthesis and lyse the symbiotic zooxanthellae. In black band disease, sulphide is produced at the coral–microbial biofilm interface, which is probably responsible for tissue death. Reports of newly emerging coral diseases and the lack of epidemiological and biochemical information on the known diseases indicate that this will become a fertile area of research in the interface between microbial ecology and infectious disease.” Eugene Rosenberg, Yael Ben-Haim, Environmental Microbiology, Volume 4, Issue 6, pages 318–326, June 2002, DOI: 10.1046/j.1462-2920.2002.00302.x. [full text]

The future of coral reefs – Knowlton (2001) “Coral reefs, with their millions of species, have changed profoundly because of the effects of people, and will continue to do so for the foreseeable future. Reefs are subject to many of the same processes that affect other human-dominated ecosystems, but some special features merit emphasis: (i) Many dominant reef builders spawn eggs and sperm into the water column, where fertilization occurs. They are thus particularly vulnerable to Allee effects, including potential extinction associated with chronic reproductive failure. (ii) The corals likely to be most resistant to the effects of habitat degradation are small, short-lived “weedy” corals that have limited dispersal capabilities at the larval stage. Habitat degradation, together with habitat fragmentation, will therefore lead to the establishment of genetically isolated clusters of inbreeding corals. (iii) Increases in average sea temperatures by as little as 1°C, a likely result of global climate change, can cause coral “bleaching” (the breakdown of coral–algal symbiosis), changes in symbiont communities, and coral death. (iv) The activities of people near reefs increase both fishing pressure and nutrient inputs. In general, these processes favor more rapidly growing competitors, often fleshy seaweeds, and may also result in explosions of predator populations. (v) Combinations of stress appear to be associated with threshold responses and ecological surprises, including devastating pathogen outbreaks. (vi) The fossil record suggests that corals as a group are more likely to suffer extinctions than some of the groups that associate with them, whose habitat requirements may be less stringent.” Nancy Knowlton, PNAS May 8, 2001 vol. 98 no. 10 5419-5425, doi: 10.1073/pnas.091092998. [full text]

Coral bleaching: the winners and the losers – Loya et al. (2001) “Sea surface temperatures were warmer throughout 1998 at Sesoko Island, Japan, than in the 10 preceding years. Temperatures peaked at 2.8 °C above average, resulting in extensive coral bleaching and subsequent coral mortality. Using random quadrat surveys, we quantitatively documented the coral community structure one year before and one year after the bleaching event. The 1998 bleaching event reduced coral species richness by 61% and reduced coral cover by 85%. Colony morphology affected bleaching vulnerability and subsequent coral mortality. Finely branched corals were most susceptible, while massive and encrusting colonies survived. Most heavily impacted were the branched Acropora and pocilloporid corals, some of which showed local extinction. We suggest two hypotheses whose synergistic effect may partially explain observed mortality patterns (i.e. preferential survival of thick-tissued species, and shape-dependent differences in colony mass-transfer efficiency). A community-structural shift occurred on Okinawan reefs, resulting in an increase in the relative abundance of massive and encrusting coral species.” Loya, Sakai, Yamazato, Nakano, Sambali, Van Woesik, Ecology Letters, Volume 4, Issue 2, pages 122–131, March 2001, DOI: 10.1046/j.1461-0248.2001.00203.x.

Climate change, coral bleaching and the future of the world’s coral reefs – Hoegh-Guldberg (1999) “Sea temperatures in many tropical regions have increased by almost 1°C over the past 100 years, and are currently increasing at ~1–2°C per century. Coral bleaching occurs when the thermal tolerance of corals and their photosynthetic symbionts (zooxanthellae) is exceeded. Mass coral bleaching has occurred in association with episodes of elevated sea temperatures over the past 20 years and involves the loss of the zooxanthellae following chronic photoinhibition. Mass bleaching has resulted in significant losses of live coral in many parts of the world. This paper considers the biochemical, physiological and ecological perspectives of coral bleaching. It also uses the outputs of four runs from three models of global climate change which simulate changes in sea temperature and hence how the frequency and intensity of bleaching events will change over the next 100 years. The results suggest that the thermal tolerances of reef-building corals are likely to be exceeded every year within the next few decades. Events as severe as the 1998 event, the worst on record, are likely to become commonplace within 20 years. Most information suggests that the capacity for acclimation by corals has already been exceeded, and that adaptation will be too slow to avert a decline in the quality of the world’s reefs. The rapidity of the changes that are predicted indicates a major problem for tropical marine ecosystems and suggests that unrestrained warming cannot occur without the loss and degradation of coral reefs on a global scale.” Ove Hoegh-Guldberg, Marine and Freshwater Research 50(8) 839 – 866, doi:10.1071/MF99078. [full text]

The Significance of Emerging Diseases in the Tropical Coral Reef Ecosystem – Hayes & Goreau (1998) “Novel pathologies of coral reef organisms, especially reef frame building scleractinian corals, have escalated during the decade between 1987 and 1997. These emerging diseases have appeared with progressively greater frequency and over wider distribution, and have revealed more diversified characteristics than ever before. The causes of most of these infections are not yet confirmed, but they evidence a gradual decline in the vital status of the coral reef ecosystem. As specific causes are identified for these afflictions, terminology will shift from non-specific descriptions, such as “white band”, “white plague”, “white pox”, “yellow band” and “black band” diseases, to etiological and pathognomonic characterizations (e.g. aspergillosis and cyanobacteriosis). Stony corals are vulnerable to sedimentation, nutrient overloading, and chemical pollution from agricultural, urban, and domestic sources. They are incapable of relocation to other sites or of self-protection from cumulative effects of exposure to nitrates, phosphates, herbicides, pesticides, and raw sewage. In contrast to stresses attributed to warm water seasonal anomalies (e.g. coral reef bleaching), stresses imparted by pathogenic micro-organisms occur throughout the calendar year, fluctuate with changing temperature, and invariably result in tissue mortality. The coral has several mechanisms for defense. The epidermis, especially in tentacles of the coral polyp, contains nematocysts which are released in response to predators. The epidermal cells also possess cilia and a flagellary apparatus which are responsible for generating microcurrents in boundary water adjacent to the organism. These currents facilitate the entry of food into the coelenteron for digestion. Mesenterial filaments extend through the epidermis, sweep the surface of the colony, initiate digestion of food particles, and eventually return to the coelenteron. Both the epidermis and the gastrodermis contain mucocytes (or “immunocytes”) which release a mucous secretion. That mucous blanket physically insulates the tissue from particulates or soluble toxins, and may also be bacteriostatic because of immunoglobulin (IgA). The recent emergence of diseases in corals may be interpreted as the consequence of (1) changing coastal ocean water quality favoring the proliferation, attachment and colonization of microbes, and (2) reduced efficiency of the coral’s normal defenses. In order to appreciate these changes, research efforts to evaluate the microbial content of reef waters and to analyze the respective roles of mucus, cilia and flagella, and nematocysts of the corals are necessary. In this study, we have begun to detail the structural, physiological, chemical, and immunological attributes of the coral. Our analysis suggests that at least some of the emerging coral diseases may be explained by a decline in the capacity of coral colonies to mount effective protection against the increasing prevalence and varied invasive strategies of marine pathogens.” Raymond L. Hayes and Nora I. Goreau, Revista Biol Trop 46: 173–185. [full text is available in the abstract page]

Coral bleaching: causes and consequences – Brown (1997) “It has been over 10 years since the phenomenon of extensive coral bleaching was first described. In most cases bleaching has been attributed to elevated temperature, but other instances involving high solar irradiance, and sometimes disease, have also been documented. It is timely, in view of our concern about worldwide reef condition, to review knowledge of physical and biological factors involved in bleaching, the mechanisms of zooxanthellae and pigment loss, and the ecological consequences for coral communities. Here we evaluate recently acquired data on temperature and irradiance-induced bleaching, including long-term data sets which suggest that repeated bleaching events may be the consequence of a steadily rising background sea temperature that will in the future expose corals to an increasingly hostile environment. Cellular mechanisms of bleaching involve a variety of processes that include the degeneration of zooxanthellae in situ, release of zooxanthellae from mesenterial filaments and release of algae within host cells which become detached from the endoderm. Photo-protective defences (particularly carotenoid pigments) in zooxanthellae are likely to play an important role in limiting the bleaching response which is probably elicited by a combination of elevated temperature and irradiance in the field. The ability of corals to respond adaptively to recurrent bleaching episodes is not known, but preliminary evidence suggests that phenotypic responses of both corals and zooxanthellae may be significant.” B. E. Brown, Coral Reefs, Volume 16, Supplement 1, S129-S138, DOI: 10.1007/s003380050249. [full text]

Tracking South Pacific Coral Reef Bleaching

by Satellite and Field Observations – Goreau et al. (1997)
“South Pacific waters with anomalously high surface temperature were tracked by satellite to identify potential sites for field study of coral reef bleaching. Areas with warm season monthly anomalies exceeding +0.9 degrees C were verified to have coral bleaching by local observers, while other areas were not affected. Comparison of 15 environmental variables, measured at 19 field sites across the area affected in 1994, shows that bleaching correlates significantly only with anomalously high temperature. Live coral cover was inversely correlated with many human population density-dependent stresses, but these were not correlated to bleaching. Observations in the Indian and Atlantic Oceans also show that coral reefs worldwide are acclimated close to their upper temperature limits and probably unable to adapt rapidly to a +1 degree C anomalous warming during the warm season.” T. J. Goreau, R. L. Hayes, and A. E. Strong, Proceedings of the 8th International Coral Reef Symposium 2:1491-1494, 1997. [full text is available in the abstract page]

Coral bleaching relative to elevated seawater temperature in the Andaman Sea (Indian Ocean) over the last 50 years – Brown et al. (1996) Without abstract. B. E. Brown, R. P. Dunne and H. Chansang, Coral Reefs, Volume 15, Number 3, 151-152, DOI: 10.1007/BF01145885.

Periodic mass-bleaching and elevated sea temperatures: bleaching of outer reef slope communities in Moorea, French Polynesia – Hoegh-Guldberg & Salvat (1995) “Mass-bleaching events (in which corals and other symbiotic invertebrates lose their zooxanthellae) have been occurring every 3 to 4 yr since 1979. The last report of widespread mass-bleaching in the Pacific (which included bleaching around French Polynesia) was in February-April 1991. This paper reports on mass-bleaching along the outer reef slope of Moorea, French Polynesia, in April 1994. Mass-bleaching was extensive at all sites visited, with corals being bleached down to 25 m. Colour loss by corals was due to low areal densities of zooxanthellae and the percentage of live coral affected ranged between 39.6 (+/- 7.12, SEM) (NW sites) and 72.4 (+/- 7.11, SEM) (NE sites). Bleaching also varied as a function of depth and included a wide range of species. Acropora spp. showed the most severe bleaching (89.0 to 100% of all colonies completely bleached) and Porites spp. showed the least amount of bleaching (12.9 to 42.5% of all colonies partly bleached). Pocillopora spp. showed intermediate bleaching (73.9 to 92.1% of all colonies either partly or completely bleached). The results of this report indicate that current bleaching is on a scale equal to that of the 1991 bleaching event. Temperatures recorded hourly at 14 m off the outer reef slope from July 1991 to August 1994 (and those from satellite sea surface temperature readings) indicate unusually warm sea temperatures in March 1994, which were approximately 1.0*C higher than the highest temperatures recorded in 1992 and 1993, years in which bleaching on a massive scale did not occur. The appearance of warmer temperatures preceded the onset of bleaching by 2 to 3 wk, which strongly confirms the hypothesis that positive thermal anomalies are responsible for recent bleaching events in the Central and Western Pacific.” Hoegh-Guldberg O, Salvat B, MEPS 121:181-190 (1995), doi:10.3354/meps121181.

Catastrophes, Phase Shifts, and Large-Scale Degradation of a Caribbean Coral Reef – Hughes (1994) “Many coral reefs have been degraded over the past two to three decades through a combination of human and natural disturbances. In Jamaica, the effects of overfishing, hurricane damage, and disease have combined to destroy most corals, whose abundance has declined from more than 50 percent in the late 1970s to less than 5 percent today. A dramatic phase shift has occurred, producing a system dominated by fleshy macroalgae (more than 90 percent cover). Immediate implementation of management procedures is necessary to avoid further catastrophic damage.” Terence P. Hughes, Science 9 September 1994: Vol. 265 no. 5178 pp. 1547-1551, DOI: 10.1126/science.265.5178.1547. [full text]

1994 coral bleaching event, Society Islands, French Polynesia – Fagerstom & Rougerie (1994) “The progression of a temperature-induced bleaching event on the barrier reef at Passe d’Arue, Tahiti, during March–April 1994 was observed at approximately weekly intervals. The event consisted of selective exaggeration of polyp colours (Montipora verneuilli, Pocillopora verrucosa), fluorescence followed by bleaching (Acropora spp.), partial-complete bleaching (Fungia spp., Montastraea curta, anemones) and commencement of polyp death. Porites (massive spp.), P. (Synarea) rus and melobesoid algae were almost untouched by the event.” J.A. Fagerstrom and F. Rougerie, Marine Pollution Bulletin, Volume 29, Issues 1-3, 1994, Pages 34-35, doi:10.1016/0025-326X(94)90423-5. [full text]

Coral reef bleaching: ecological perspectives – Glynn (1993) “Coral reef bleaching, the whitening of diverse invertebrate taxa, results from the loss of symbiotic zooxanthellae and/or a reduction in photosynthetic pigment concentrations in zooxanthellae residing within the gastrodermal tissues of host animals. Of particular concern are the consequences of bleaching of large numbers of reef-building scleractinian corals and hydrocorals. Published records of coral reef bleaching events from 1870 to the present suggest that the frequency (60 major events from 1979 to 1990), scale (co-occurrence in many coral reef regions and often over the bathymetric depth range of corals) and severity (>95% mortality in some areas) of recent bleaching disturbances are unprecedented in the scientific literature. The causes of small scale, isolated bleaching events can often be explained by particular stressors (e.g., temperature, salinity, light, sedimentation, aerial exposure and pollutants), but attempts to explain large scale bleaching events in terms of possible global change (e.g., greenhouse warming, increased UV radiation flux, deteriorating ecosystem health, or some combination of the above) have not been convincing. Attempts to relate the severity and extent of large scale coral reef bleaching events to particular causes have been hampered by a lack of (a) standardized methods to assess bleaching and (b) continuous, long-term data bases of environmental conditions over the periods of interest. An effort must be made to understand the impact of bleaching on the remainder of the reef community and the long-term effects on competition, predation, symbioses, bioerosion and substrate condition, all factors that can influence coral recruitment and reef recovery. If projected rates of sea warming are realized by mid to late AD 2000, i.e. a 2°C increase in high latitude coral seas, the upper thermal tolerance limits of many reef-building corals could be exceeded. Present evidence suggests that many corals would be unable to adapt physiologically or genetically to such marked and rapid temperature increases.” P. W. Glynn, Coral Reefs, Volume 12, Number 1, 1-17, DOI: 10.1007/BF00303779.

Effects of disturbance on coral communities: bleaching in Moorea, French Polynesia – Gleason (1993) “This study examines patterns of susceptibility and short-term recovery of corals from bleaching. A mass coral bleaching event began in March, 1991 on reefs in Moorea, French Polynesia and affected corals on the shallow barrier reef and to >20 m depth on the outer forereef slope. There were significant differences in the effect of the bleaching among common coral genera, with Acropora, Montastrea, Montipora, and Pocillopora more affected than Porites, Pavona, leptastrea or Millepora. Individual colonies of the common species of Acropora and Pocillopora were marked and their fate assessed on a subsequent survey in August, 1991 to determine rates of recovery and mortality. Ninety-six percent of Acropora spp. showed some degree of bleaching compared to 76% of Pocillopora spp. From March to August mortality of bleached colonies of Pocillopora was 17%, 38% recovered completely, and many suffered some partial mortality of the tissue. In contrast, 63% of the Acropora spp. died, and about 10% recovered completely. Generally, those colonies with less than 50% of the colony area affected by the bleaching recovered at a higher rate than did those with more severe bleaching. Changes in community composition four months after the event began included a significant decrease only in crustose algae and an increase in cover of filamentous algae, much of which occupied plate-like and branching corals that had died in the bleaching event. Total coral cover and cover of susceptible coral genera had declined, but not significantly, after the event.” M. G. Gleason, Coral Reefs, Volume 12, Numbers 3-4, 193-201, DOI: 10.1007/BF00334479.

An Assessment of Global Warming Stress on Caribbean Coral Reef Ecosystems – Atwood et al. (1992) “There is evidence that stress on coral reef ecosystems in the Caribbean region is increasing. Recently numerous authors have stated that the major stress results from “abnormally high” seasonal sea surface temperatures (SST) and have implicated global warming as a cause, stating that recent episodes of coral bleaching result therefrom. However, an analysis of available SST data sets shows no discernible warming trend that could cause an increase in coral bleaching. Given the lack of long-term records synoptic with observations of coral ecosystem health, there is insufficient evidence available to label temperatures observed in coincidence with recent regional bleaching events as “abnormally” high.” Atwood, Donald K.; Hendee, James C.; Mendez, Antonio, Bulletin of Marine Science, Volume 51, Number 1, July 1992 , pp. 118-130(13).

Coral reef bleaching in the 1980s and possible connections with global warming – Glynn (1991) “Scleractinian corals and their symbiotic dinoflagellate algae build massive, wave-resistant coral reefs that are pre-eminent in shallow tropical seas. This mutualism is especially sensitive to numerous environmental stresses, and has been disrupted frequently during the past decade. Increased seawater temperatures have been proposed as the most likely cause of coral reef bleaching, and it has been suggested that the recent large-scale disturbances are the first biological indication of global warming. This article describes recent bleaching events and their possible link with sea warming and other environmental stresses, and offers some speculation on the fate of coral reefs if the Earth enters a sustained period of warming.” Peter W. Glynn, Trends in Ecology & Evolution, Volume 6, Issue 6, June 1991, Pages 175-179, doi:10.1016/0169-5347(91)90208-F.

Damage and recovery of coral reefs affected by El Niño related seawater warming in the Thousand Islands, Indonesia – Brown & Suharsono (1990) “Extensive coral bleaching occurred during sea-water warming (as a result of the 1982/3 El Niño Southern Oscillation event) in 1983 on the shallow reefs in the Java Sea. Mean seawater temperatures rose by 2–3° C over a six month period with values greater than 33° C being recorded between 1200–1500 h. As many as 80–90% of corals died on the reef flats at the study sites, with the major casualties being branching species in the genera Acropora and Pocillopora. Five years after the event the community structure of the study sites has recovered significantly, though coral cover is still 50% of its former level. Contrasting patterns of recovery at two selected sites, in close proximity to each other, are discussed.” B. E. Brown and Suharsono, Coral Reefs, Volume 8, Number 4, 163-170, DOI: 10.1007/BF00265007.

Widespread Coral Mortality and the 1982–83 El Niño Warming Event – Glynn (1984) “The massive ‘bleaching’ (loss of zooxanthellae) and death of reef corals that occurred in one area (Gulf of Chiriquí) on the Pacific side of Panamá and in the Galápagos Islands during February—April 1983 continued in these areas until September—October 1983, resulting in a catastrophic disturbance. Similar episodes have been reported subsequently throughout much of the tropical eastern Pacific region (Costa Rica, the entire Pacific coast of Panamá, and Colombia), in the central and western Pacific Ocean, in parts of the western Atlantic Ocean (Caribbean coasts of Costa Rica, Panamá, and Colombia), and in the Florida Keys and Bahama Islands.” Peter W. Glynn, Environmental Conservation (1984), 11: 133-146, DOI: 10.1017/S0376892900013825.

There's a tremendous amount of information out there. People have dedicated their lives to accumulating it. It's no surprise that amateurs with an axe to grind fixate on a few pieces of the scientific discussion and mistake the part for the whole, especially with the ridiculous "post-normal science" crowd striving to convince them that they are one penetrating insight away from turning the world on its head. I for one am very happy that we have people who do this for a living.

Tuesday, March 1, 2011

Minor myths: Judith Curry and the failure to persuade

Judith Curry has given us a nice summary of a denier fallacy which gets floated in blog posts and comments all the time:

If climate scientists can’t convince level 2′s and also level 3′s, people who are looking at the arguments carefully, reading the primary literature, and analyzing data, then it seems to me that the arguments can’t be that strong (or the confidence levels can’t be that high).

If we state this as a general proposition, that proposition would be:

People are persuaded if strong arguments are presented to them, provided they are intelligent enough to read and analyze data.

Or, since most people acknowledge that strongly biased people can ignore or distort data to affirm their preexisting beliefs, we might simply state it as "Intelligent people are never strongly biased."

This is the "Well you haven't convinced me" fallacy: the idea that the responsibility of scientists is to convince everyone, and if a denier withholds their approval of a line of argument, then it is those who argue that have failed -- failed to persuade.

Let's consider briefly some of the ideas that have had intelligent and articulate defenders over the years. Totalitarian communism. Eugenics. White supremacism, colonialism, absolute monarchy, religious fundamentalism. All have had aggressive and well-read advocates, as do contemporary anti-science movements like the anti-vaccine movement and creationism.

Sadly, there is no evidence in support of the proposition that intelligence is a protective factor in the embrace of ideological filters. Nor is it true that bias and self-justification -- concepts that has been extensively studied and found to be incredibly powerful -- deprive us of the ability to read and analyze data; the analysis in question just turns out not to be very good, cherry-picked and misattributed and otherwise given a good working over by the subject's confirmation bias.

If anything, it's easier to become attached to an ideology and defend it from all comers when one is educated and facile with the source material. The test of an argument in science is whether it can stand up to scientific critique, not whether it can persuade people who have already made up their minds and invested a considerable portion of their self-regard in their dissident position.