Tag: climate change

The Shallow Back Reef Environment of Ofu, American Samoa

Writing as background for their work, the six-member research team of Koweek et al. (2015) cite several concerns about the future of Earth’s corals that have been projected to result from the so-called twin evils of global warming and ocean acidification, including “coral bleaching (Glynn, 1993; Hughes et al., 2003; van Hooidonk et al., 2013), increased dissolution and bioerosion (Andersson and Gledhill, 2013; Dove et al., 2013; Reyes-Nivia et al., 2013), decreased biodiversity (Fabricius et al., 2011), and shifts toward algal-dominated reefs (Hoegh-Guldberg et al., 2007; Kroeker et al., 2010; 2013).” However, despite these concerns, which have captured the attention of scientists and policy makers for more than two decades now, such worries may well be overestimated and overplayed.

The reason for such growing optimism has to do with the corals themselves, which along with other marine organisms appear to have an inherent ability “of controlling their own biogeochemical environments.” Such biologically-mediated controls, if they are of sufficient magnitude, could potentially offset future changes in the marine environment brought about by rising atmospheric CO2 (projected ocean warming and pH decline). It is therefore of considerable importance for scientists to continue investigating these biological feedbacks in order to better ascertain the future of these precious marine species, for as noted by Koweek et al., “the paradigm of coral reefs as passive responders to their biogeochemical environments is rapidly changing.”

In further expanding the scientific knowledge on this important topic, the six American researchers set out to conduct a “short, high-resolution physical and biogeochemical pilot field study” on the back reefs of Ofu, American Samoa, where they measured a number of hydrodynamic and biogeochemical parameters there over a seven-day period in November, 2011. The specific study location was Pool 100 (14.185°S, 169.666°W), a shallow lagoon containing 85 coral species and various kinds of crustose coralline algae and non-calcifying algae. Koweek et al. selected Pool 100 because, as they state, shallow back reefs “commonly experience greater thermal and biogeochemical variability owing to a combination of coral community metabolism, environmental forcing, flow regime, and water depth.”

Results of their data collection and analysis revealed that temperatures within the shallow back reef environment were consistently 2-3°C warmer during the day than that observed in the offshore environment. In addition, and as expected, the ranges of the physical and biogeochemical parameters studied in Pool 100 greatly exceeded the variability observed in the open ocean. Inside Pool 100, the pH values fluctuated between a low of 7.80 and a high of 8.39 across the seven days of study, with daily ranges spanning between 0.5 and 0.6 of a unit (Figure 1). What is more, Koweek et al. report that the reef community in Pool 100 spent far more time outside of the offshore pH range than within it (pH values were between 8.0 and 8.2 during only 30 percent of the observational period, less than 8.0 for 34 percent of the time and greater than 8.2 for the remaining 36 percent of the observations). Additional measurements and calculations indicated that these fluctuations in pH were largely the product of community primary production and respiration, as well as tidal modulation and wave-driven flow.

Figure 1. Time series of pHT (top panel) and pCO2 (bottom panel) in Pool 100, Ofu, American Samoa from November 16-20, 2011. Vertical blue and orange lines show the occurrence of high and low tides, respectively. Gray vertical shading shows the period from sundown to sunrise. The different colored circles represent data that were collected from different locations in Pool 100 and the dashed horizontal black lines represent the mean value of each parameter in the offshore ocean. Adapted from Koweek et al. (2015).

Figure 1. Time series of pHT (top panel) and pCO2 (bottom panel) in Pool 100, Ofu, American Samoa from November 16-20, 2011. Vertical blue and orange lines show the occurrence of high and low tides, respectively. Gray vertical shading shows the period from sundown to sunrise. The different colored circles represent data that were collected from different locations in Pool 100 and the dashed horizontal black lines represent the mean value of each parameter in the offshore ocean. Adapted from Koweek et al. (2015).

Commenting on these and other of their findings, Koweek et al. write that “our measurements have provided insight into the physical–biogeochemical coupling on Ofu.” And that insight, they add, “suggests a significantly more nuanced view of the fate of coral reefs” than the demise of global reef systems that is traditionally forecast under the combined stresses of climate change and ocean acidification.

Indeed, if these ecosystems presently thrive under such variable (and more severe) environmental conditions than those predicted for the future—which conditions are largely derived and modulated by themselves—why wouldn’t they persist?



Andersson, A.J. and Gledhill, D. 2013. Ocean acidification and coral reefs: effects on breakdown, dissolution, and net ecosystem calcification. Annual Review of Marine Science 5: 321-348.

Dove, S.G., Kline, D.I., Pantos, O., Angly, F.E., Tyson, G.W. and Hoegh-Guldberg, O. 2013. Future reef decalcification under a business-as-usual CO2 emission scenario. Proceedings of the National Academy of Sciences, USA 110: 15342-15347.

Fabricius, K.E., Langdon, C., Uthicke, S., Humphrey, C., Noonan, S.H.C., De’ath, G., Okazaki, R., Muehllehner, N., Glas, M.S. and Lough, J.M. 2011. Losers and winners in coral reefs acclimatized to elevated carbon dioxide concentrations. Nature Climate Change 1: 165-169.

Glynn, P.W. 1993. Coral reef bleaching: ecological perspectives. Coral Reefs 12: 1-17.

Hoegh-Guldberg, O., Mumby, P.J., Hooten, A.J., Steneck, R.S., Greenfield, P., Gomez, E., Harvell, C.D., Sale, P.F., Edwards, A.J., Caldeira, K., Knowlton, N., Eakin, C.M., Iglesias-Prieto, R., Muthiga, N., Bradbury, R.H., Dubi, A. and Hatziolos, M.E. 2007. Coral reefs under rapid climate change and ocean acidification. Science 318: 1737-1742.

Hughes, T.P., Baird, A.H., Bellwood, D.R., Card, M., Connolly, S.R., Folke, C., Grosberg, R., Hoegh-Guldberg, O., Jackson, J.B.C., Kleypas, J.A., Lough, J.M., Marshall, P., Nystrom, M., Palumbi, S.R., Pandolfi, J.M., Rosen, B. and Roughgarden, J. 2003. Climate change, human impacts, and the resilience of coral reefs. Science 301: 929-933.

Koweek, D.A., Dunbar, R.B., Monismith, S.G., Mucciarone, D.A., Woodson, C.B. and Samuel, L. 2015. High-resolution physical and biogeochemical variability from a shallow back reef on Ofu, American Samoa: an end-member perspective. Coral Reefs 34: 979-991.

Kroeker, K.J., Kordas, R.L., Crim, R.N. and Singh, G.G. 2010. Meta-analysis reveals negative yet variable effects of ocean acidification on marine organisms. Ecology Letters 13: 1419-1434.

Kroeker, K.J., Kordas, R.L., Crim, R.N., Hendriks, I.E., Ramajo, L., Singh, G.S., Duarte, C.M. and Gattuso, J.-P. 2013. Impacts of ocean acidification on marine organisms: quantifying sensitivities and interaction with warming. Global Change Biology 19: 1884-1896.

Reyes-Nivia, C., Diaz-Pulido, G., Kline, D.I., Hoegh-Guldberg, O. and Dove, S.G. 2013. Ocean acidification and warming scenarios increase microbioerosion of coral skeletons. Global Change Biology 19: 1919-1929.

van Hooidonk, R., Maynard, J.A. and Planes, S. 2013. Temporary refugia for coral reefs in a warming world. Nature Climate Change 3: 508-511.

You Ought to Have a Look: Our Energy Future, Science Regress, and a Greening Earth

You Ought to Have a Look is a feature from the Center for the Study of Science posted by Patrick J. Michaels and Paul C. (“Chip”) Knappenberger.  While this section will feature all of the areas of interest that we are emphasizing, the prominence of the climate issue is driving a tremendous amount of web traffic.  Here we post a few of the best in recent days, along with our color commentary.

We’ll jump right into this week by highlighting an appearance by Manhattan Institute senior fellow Mark Mills on The Federalist’s Radio Hour. During his time on the show, Mills explains how the foreseeable future is going to play out when it comes to global energy production and why he says that even if you were concerned about climate change, “there really isn’t anything you can do about it.” 

Mills is one of the leading thinkers and analysts on energy systems, energy markets, and energy policy, bringing often overlooked and deeply-buried information to the forefront.

During his nearly hour-long radio segment, Mills discusses topics ranging from climate change, the world’s future energy mix, the role of technological advances, and energy policy as well as giving his opinions on both Bills Gates’ and Pope Francis’ take on all of the above. It is an entertaining and informative interview.

As a taste, here’s a transcript of a small segment:

In the life we live, and the world we live in, we have to do two things, one is deal with reality [current understanding of physics] and the moral consequences of that, and we can have aspirations. If the aspiration, which Bill Gates’ is, is to use fewer hydrocarbons, we need to support basic research.

We don’t subsidize stuff. The reason we don’t subsidize stuff and make energy more expensive, is because, for me, it is morally bankrupt to increase the cost of energy for most people in most of the world. Energy should be cheaper, not more expensive. We use energy to make our lives better. We use energy to make our lives safer. We use energy to make our lives more enjoyable. Everything that we care about in the world, safety, convenience, freedom, costs energy. [emphasis added]

Mark Mills’ sentiment closely matches that which Alex Epstein explained to Congress a few weeks back and that we highlighted in our last edition. 

If you can find any time to listen to a little or a lot of Mills’ full interview, you’ll probably find that what he says to make a lot of sense. Funny, though, how much of it seems to have escaped some folks.

Next up is an article in the current issue of First Things authored by Walter Wilson titled “Scientific Regress.” If you think the title is provocative, you ought to have a look at the rest of the piece beginning with the first line “The problem with ­science is that so much of it simply isn’t.” Instead, it reflects the results of a gamed system driven by pre-conceived ideas often emanating from the science/political establishment.

A Historic Perspective on the Greenland Ice Sheet and its Contribution to Global Sea Level

One of the most feared of all model-based projections of CO2-induced global warming is that temperatures will rise enough to cause a disastrous melting/destabilization of the Greenland Ice Sheet (GrIS), which would raise global sea level by several meters. But how likely is this scenario to occur? And is there any way to prove such melting is caused by human activities?

The answer to this two-part question involves some extremely complex and precise data collection and understanding of the processes involved with glacial growth and decay. Most assuredly, however, it also involves a scientifically accurate assessment of the past history of the GrIS, which is needed to provide a benchmark for evaluating its current and future state. To this end, a recent review paper by Vasskog et al. (2015) provides a fairly good summary of what is (and is not) presently known about the history of the GrIS over the previous glacial-interglacial cycle. And it yields some intriguing findings.

Probably the most relevant information is Vasskog et al.’s investigation of the GrIS during the last interglacial period (130-116 ka BP). During this period, global temperatures were 1.5-2.0°C warmer than the peak warmth of the present interglacial, or Holocene, in which we are now living. As a result of that warmth, significant portions of the GrIS melted away. Quantitatively, Vasskog et al. estimate that during this time (the prior interglacial) the GrIS was “probably between ~7 and 60% smaller than at present,” and that that melting contributed to a rise in global sea level of “between 0.5 and 4.2 m.” Thus, in comparing the present interglacial to the past interglacial, atmospheric CO2 concentrations are currently 30% higher, global temperatures are 1.5-2°C cooler, GrIS volume is from 7-67% larger, and global sea level is at least 0.5-4.2 m lower, none of which signal catastrophe for the present.

Clearly, therefore, there is nothing unusual, unnatural or unprecedented about the current interglacial, including the present state of the GrIS. Its estimated ice volume and contribution to mean global sea level reside well within their ranges of natural variability, and from the current looks of things, they are not likely to depart from those ranges any time soon.



Reyes, A.V., Carlson, A.E., Beard, B.L., Hatfield, R.G., Stoner, J.S., Winsor, K., Welke, B. and Ullman, D.J. 2014. South Greenland ice-sheet collapse during Marine Isotope Stage 11. Nature 510: 525–528.

Vasskog, K., Langebroek, P.M., Andrews, J.T., Nilsen, J.E.Ø. and Nesje, A. 2015. The Greenland Ice Sheet during the last glacial cycle: Current ice loss and contribution to sea-level rise from a palaeoclimatic perspective. Earth-Science Reviews 150: 45-67.

You Ought to Have a Look: Paris Climate Agreement

You Ought to Have a Look is a feature from the Center for the Study of Science posted by Patrick J. Michaels and Paul C. (“Chip”) Knappenberger.  While this section will feature all of the areas of interest that we are emphasizing, the prominence of the climate issue is driving a tremendous amount of web traffic.  Here we post a few of the best in recent days, along with our color commentary.

With Earth Day and the grand signing ceremony for the Paris Climate Agreement just around the corner, we thought it apt to highlight some relevant stories from around the web, particularly those critical of the central climate control enterprise.

Recall that we have pointed out the Paris Climate Agreement represents little more than a business-as-usual approach that has been spun to suggest that it represents a collective, international effort in response to a climate change “concern.” Increasing opportunities for riding your bike (etc.) now have been rebranded as efforts to save the world. Right.

We’ve shown that the U.S. pledge under the Paris “Don’t Call It a Treaty” Agreement, while a bit more aggressive than many, turns out to basically be impossible. Putting our name on such pledge seems a bit disingenuous, to put it mildly.

On top of all this comes a new economic analysis from the Heritage Foundation that basically shows that the U.S. intension under the Agreement would be mucho bad news. Here are the Key Points from the report “Consequences of Paris Protocol: Devastating Economic Costs, Essentially Zero Environmental Benefits”:


Our Friends at CEI Face a Subpoena Over Climate Dissent

The campaign to attach legal consequences to supposed “climate denial” has now crossed a fateful line. Yesterday:

The Competitive Enterprise Institute (CEI) today denounced a subpoena from Attorney General Claude E. Walker of the U.S. Virgin Islands that attempts to unearth a decade of the organization’s materials and work on climate change policy. This is the latest effort in an intimidation campaign to criminalize speech and research on the climate debate, led by New York Attorney General Eric Schneiderman and former Vice President Al Gore….

The subpoena requests a decade’s worth of communications, emails, statements, drafts, and other documents regarding CEI’s work on climate change and energy policy, including private donor information. It demands that CEI produce these materials from 20 years ago, from 1997-2007, by April 30, 2016.

CEI General Counsel Sam Kazman said the group “will vigorously fight to quash this subpoena. It is an affront to our First Amendment rights of free speech and association.” More coverage of the subpoena at the Washington Times and Daily Caller.

A few observations:

  • If the forces behind this show-us-your-papers subpoena succeed in punishing (or simply inflicting prolonged legal harassment on) a group conducting supposedly wrongful advocacy, there’s every reason to think they will come after other advocacy groups later. That includes yours.
  • This article in the Observer details the current push to expand the probe of climate advocacy, which first enlisted New York AG Eric Schneiderman and then California’s Kamala Harris — into a broader coalition of AGs, with Massachusetts and the Virgin Islands just having signed on. More than a dozen others, such as Maryland Attorney General Brian Frosh, seem to be signaling support but have not formally jumped in. More: Peggy Little, Federalist Society.
  • CEI people, many of whom we count as longtime friends and allies in the pro-liberty policy community, have been active critics of the Schneiderman effort, with Hans Bader, a senior attorney there, highly critical just a week ago.
  • In these working groups of attorneys general, legal efforts are commonly parceled out among the states in a deliberate and strategic way, with particular tasks being assigned to AGs who have comparative advantage in some respect (such as an unusually favorable state law to work with, or superior staff expertise or media access). Why would one of the most politically sensitive tasks of all — opening up a legal attack against CEI, a long-established nonprofit well known in Washington and in libertarian and conservative ideological circles — be assigned to the AG from a tiny and remote jurisdiction? Is it that a subpoena coming from the Virgin Islands is logistically inconvenient to fight in some way, or that local counsel capable of standing up to this AG are scarce on the ground there, or that a politician in the Caribbean is less exposed to political backlash from CEI’s friends and fans than one in a major media center? Or what?
  • I recommend checking out the new Free Speech and Science Project, which intends to fight back against criminalization of advocacy by, among other things, organizing legal defense and seeking to hold officials accountable for misusing the law to attack advocacy.
  • This is happening at a time of multiple, vigorous, sustained legal attacks on what had been accepted freedoms of advocacy and association. As I noted yesterday in a piece in this space, Sen. Elizabeth Warren has just demanded that the Securities and Exchange Commission investigate several large corporations that have criticized her pet plan to impose fiduciary legal duties on retirement advisors, supposedly on the ground that it is a securities law violation for them to be conveying to investors a less alarmed view of the regulations’ effect than they do in making their case to the Labor Department. This is not particularly compelling as securities law, but it’s great as a way to chill speech by publicly held businesses.

[cross-posted, with slight changes, from Overlawyered]

A Plant Pathogen that Can’t Take the Heat

Plant pathogens have long been a thorn in the side of the agricultural industry, reducing crop production between 10-16 percent annually and costing an estimated $220 billion in economic losses (Chakraborty and Newton, 2011). What is more, there are concerns that such damages may increase in the future if temperatures rise as predicted by global climate models in response to CO2-induced global warming. Noting these concerns, Sabburg et al. (2015) write that “to assess potential disease risks and improve our knowledge of pathogen strengths, flexibility, weakness and vulnerability under climate change, a better understanding of how pathogen fitness will be influenced is paramount.”

In an attempt to obtain that knowledge, the team of four Australian researchers set out to investigate the impact of rising temperatures on Fusarium pseudograminearum, the “predominant pathogen causing crown rot of wheat in Australia” that is responsible for inducing an average of AU$79 million in crop losses each year. More specifically, they examined “whether the pathogenic fitness, defined as a measure of survival and reproductive success of F. pseudograminearum causing crown rot in wheat, is influenced by temperature under experimental conditions.”

The experiment was conducted in controlled-environment glasshouses at the Queensland Crop Development Facility in Queensland, Australia, where eleven lines of wheat were grown under four day/night temperature treatments (15/15°C, 20/15°, 25/15° and 28/15°C for 14-hour days and 10-hour nights). The first three treatments were representative of “the range of average maximum temperatures of the various wheat-growing regions across Australia,” whereas the fourth (28/15°C) treatment was intended to simulate a future warming scenario. The minimum temperatures of all treatments were kept at 15°C because “night-time temperatures over the last 50 years in the large majority of wheat-growing regions across Australia have not shown an increasing temperature trend in all seasons.” With respect to the eleven wheat lines, they were selected based on known susceptibilities and resistances to crown rot. Fourteen days after sowing a portion of each line was infected with F. pseudograminearum and then grown to maturity.

So what did the researchers find?

With respect to disease severity, Sabburg et al. report it was highest under the lowest temperature treatment and declined with increasing temperature (Figure 1a), and this general reduction was noted in all of the eleven wheat lines. Similarly, pathogen biomass was also reduced as treatment temperature increased (Figure 1b). According to the researchers, “on average, warming reduced pathogen biomass in stem base (PB-S) by 52% at either 25/15°C or 28/15°C compared with the biomass at 15/15°C.” And it also decreased the amount of relative pathogen biomass from the stem base to flag leaf node. (The flag leaf is to top leaf on the plant.)

A third fitness measure of F. pseudograminearum – deoxynivalenol (also known as “vomitoxin,” for an obvious reason) content (DON) – was also reduced in the stem base and flag leaf node tissue as temperature treatment increased. And the significance of this finding was noted by the authors as “an encouraging result if we consider temperature rises in the future,” because “DON can make food sources including wheat grains unsafe for human or animal consumption.” That’s putting it mildly!

Figure 1. Effect of temperature on (Panel A) disease severity as expressed by the length of stem base browning (cm) and (Panel B) relative pathogen biomass in stem base (PB-S) and flag leaf node tissue (PB-F) as measured by Fusarium DNA relative to wheat DNA. All measurements in wheat plants were made at maturity following stem base inoculation by Fusarium pseudograminearum. Adapted from Sabburg et al. (2015).

Figure 1. Effect of temperature on (Panel A) disease severity as expressed by the length of stem base browning (cm) and (Panel B) relative pathogen biomass in stem base (PB-S) and flag leaf node tissue (PB-F) as measured by Fusarium DNA relative to wheat DNA. All measurements in wheat plants were made at maturity following stem base inoculation by Fusarium pseudograminearum. Adapted from Sabburg et al. (2015).

In light of the above results, Sabburg et al. conclude that “this study has clearly established that temperature influences the overall fitness of F. pseudograminearum,” and that “based on our findings, warmer temperatures associated with climate change may reduce overall pathogenic fitness of F. pseudograminearum.” And given the annual production and monetary damages inflicted by this pathogen on wheat, this is news worth both reporting and celebrating!



Chakraborty, S. and Newton, A.C. 2011. Climate change, plant diseases and food security: an overview. Plant Pathology 60: 2-14.

Sabburg, R., Obanor, F., Aitken, E. and Chakraborty, S. 2015. Changing fitness of a necrotrophic plant pathogen under increasing temperature. Global Change Biology 21: 3126-3137.


You Say Meethane, I Say Meth-ane, Let’s Agree We Don’t Know Where It’s Coming From

Global Science Report is a weekly feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”

Atmospheric concentrations of methane (CH4)—a greenhouse gas many times more potent than carbon dioxide (at least over shorter time scales)—have begun rising after a hiatus from 1999-2006 that defied all expectations. No one knows for sure why—why they stood still, or why they started up again.

There is a lot of research underway looking into the causes of the observed methane behavior and at least three new studies have reported results in the scientific literature in the past couple of months.

The findings are somewhat at odds with each other.

In February, a study led by Alex Turner, from Harvard University’s School of Engineering and Applied Sciences, was published that examined methane emissions from the US over the past 10 years or so. The researchers compared observations taken from orbiting satellites to observations made from several sites on the earth’s surface. They reported over the past decade “an increase of more than 30% in US methane emissions.” And this increase was so large as to “suggest that increasing US anthropogenic methane emissions could account for up to 30-60% of [the] global increase.”

However, the methodologies employed by Turner et al. were insufficient for determining the source of the enhanced emissions. While the authors wrote that “[t]he US has seen a 20% increase in oil and gas production and a 9-fold increase in shale gas production from 2002 to 2014” they were quick to point out that “the spatial pattern of the methane increase seen by [satellite] does not clearly point to these sources” and added that “[m]ore work is needed to attribute the observed increase to specific sources.”

Perhaps most interestingly, Turner and colleagues note that “national inventory estimates from the US Environmental Protection Agency (EPA) indicate no significant trend in US anthropogenic methane emissions from 2002 to present”—a stark contrast to their findings, and a potential embarrassing problem for the EPA. But, never fear, the EPA is on it. The EPA is now actively re-examining its methane inventory and seems to be in the process of revising it upwards, perhaps even so much as to change its previous reported decline in methane emissions to an increase. Such a change would have large implications for the US’s ability to keep the pledge made at the U.S. 2015 Climate Conference in Paris.

However, the Turner et al. results have been called into question by a prominently-placed study in Science magazine just a couple of weeks later. The Science study was produced by a large team led by Hinrich Schaefer of New Zealand’s National Institute of Water and Atmospheric Research.

Schaefer and colleagues analyzed the changes in the isotopic ratios of carbon in the methane contained in samples of air within ice cores, archived air samples, and more recent measurement systems. Different sources of methane contain different mixtures of methane isotopes, related to how long ago the methane was formed. Using this information, the authors developed a model for trying to back out the methane sources from the well-mixed atmospheric samples. Although such a procedure is somewhat tunable (i.e., you can get pretty much any answer you want (kind of like climate models!)), the authors are pretty confident in their final results.