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The distinction between true scepticism and denial

By Don Aitkin | September 4, 2016

I came across the phrase in the title, and followed a link to a recent journal article which for once was available on open access. Entitled ‘Science and the Public: Debate, Denial, and Skepticism’,  it looked interesting. You can read it here. The four authors come from different fields, and propose to outline ‘the distinction between true scepticism and denial’. They also offer some guidelines to help researchers, and interested members of the public, decide how to deal with enquiries, on the one hand,  and problems which people see in published science, on the other.

The reader is brought into the area of ‘climate change’ at once. The controversy surrounding climate change is just one example of a polarized public debate that seems remote and detached from the actual state of science: Within the scientific community, there is a pervasive consensus that the Earth is warming from greenhouse gas emissions (Anderegg, Prall, Harold, & Schneider, 2010; Cook et al., 2013; Doran & Zimmerman, 2009; Oreskes, 2004; Shwed & Bearman, 2010), but outside science there is entrenched denial of this fact in some sectors of society (e.g., Dunlap, 2013; Lewandowsky, Gignac, & Oberauer, 2013).               [my emphasis]

Whoops! Substantively, ‘climate change’ is not simply whether the planet has warmed through greenhouse gas emissions. More important and related questions include, for example, by how much has it warmed, what else has been at work besides greenhouse gases, is the warming unprecedented or not, does it matter anyway (isn’t warming better than cooling?), and many others. Pedantically, there is no need for a consensus to be graced with the adjective pervasive. If it is a consensus then it is by definition pervasive, meaning ‘permeated’, ‘diffused through’, etc.

Then interested readers might wonder where to find the entrenched denial of the supposed fact that the Earth is warming from greenhouse gas emissions. The sceptical community for the most part, I think, accepts that greenhouse gas emissions have contributed to the warming that has occurred over the past century or so (which is not quite the same thing). There are a few dragon-slayers who don’t agree. But entrenched denial? I’m not aware of it. The links don’t help, since Dunlap 2013 is a study of 108 climate change denial books with most of the interest being in their supposed links to business groups. The Lewandowsky link is even less helpful, as well as being an intellectually dreadful paper. I don’t know quite what I would expect to find as an example of entrenched denial in opposition to pervasive consensus, but there’s no evidence for it here. To continue:

Media reports occasionally even proclaim that warming has stopped (Ridley, 2014) or that we are headed for global cooling (e.g., Rose, 2013). These propositions have no scientific support …

Well, Matt Ridley’s op. ed. in the Wall Street Journal may not be top-of-the-line science, though he refers to the science, but the UK Met Office did indeed agree that there was a hiatus in warming, and that it would continue until 2017. The scientists who propose the possibility of cooling are solar physicists, for the most part, and their views may be wrong. But the ‘cooling’  view does have some scientific support (see, for example, here).

These introductory remarks are a little jarring, in the context of the pure bromide that is to come. Public debate and scepticism are essential to a functioning democracy. Indeed scepticism has been shown to enable people to differentiate more accurately between truth and falsehood. How could we disagree? So how do we tell when what we are getting is scientific fact or denial? Ah, you see, there are three factors that are always present when denialists are involved. First, they make stuff up. Second, denial commonly invokes notions of conspiracies. (I think Dunlap 2013, mentioned above, is an excellent example of the way in which conspiracies can be invoked, but I don’t think the authors had him in mind.). Third, denialists engineer personal and professional attacks on scientists both in public and behind the scenes, and issue prolific complaints to scientists’ host institutions with allegations of research conduct. Two of the authors of this article claim to have experienced such behaviour.

The authors claim, on the basis of what they call recent evidence, is  that up to US$1billion flows into foundations and think tanks in the U.S. every year that are dedicated to political lobbying for various issues. One of the principal objectives of this network is to support a climate “counter movement” that seeks to reframe public discourse surrounding climate change from one of overwhelming scientific consensus to one of doubt, debate, and uncertainty (Brulle, 2014; Plehwe, 2014). To illustrate, more than 90% of recent books that dismiss environmental problems have been linked to conservative think tanks (Jacques, Dunlap, & Freeman, 2008), and such books typically never undergo peer review (Dunlap & Jacques, 2013). This does look like conspiracy stuff to me, on first reading, but again, I doubt the authors had this in mind either.

Now comes more bromide: In a democracy, calls for genuine debate are to be welcomed and must be taken seriously. Given that scientific issues can have far-reaching political, technological, or environmental consequences, greater involvement of the public can only be welcome and made led to better policy outcome. Who could disagree? We are given a small example of how this has worked in practice (it is not in climate change).  Notwithstanding the public’s entitlement to be involved in issues that are scientifically informed, scientific debates must still be conducted according to the rules of science. Arguments must be evidence-based and they are subject to peer review before they become provisionally accepted. Hang on there! If arguments have to be evidence-based, and the evidence doesn’t support them, what then? Do we really have to wait for good policy until the peer-review process (something that applies almost solely to academic work) has considered the matter? In the climate science arena even well-credentialled sceptical scientists have found it hard to get critical papers accepted for publication.

In the matter of disagreement, the two first-named authors acknowledge the uncertainty in climate projections, but note that contrary to popular intuition, any uncertainty provides even greater impetus for climate mitigation. I’ve come across this line of argument before, and have to go along with ‘popular intuition’ here. If there is uncertainty about whether something needs to be done, because the evidence is weak or equivocal, it would seem strange indeed to say ‘Hah! That’s even more reason to go down my chosen path!’ I am open to persuasion, but not to this kind of assertion.

What I think is happening in this strange, muddled and evidence-free paper is a kind of explicit argument that peer review is the only way to go, if only because the blogospherical world (which the authors denounce) has very little in the way of support for the supposed consensus. By now the title of the paper has been forgotten by the authors, and we get this: People who deny scientific facts that they find challenging or unacceptable, by contrast, are by and large not skeptics. On the contrary, they demonstrably shy away from scientific debate by avoiding the submission of their ideas to peer review. One has to say, again, that peer review is for academics and is not the gold standard for science. Bad data, bad argument and self-interest are usually quickly discovered, and any proposition that results from them is usually dismissed, or at least put aside. What distinguishes ‘climate change’ is that policies like the carbon tax came before the science was properly in (it still isn’t), and for political reasons the policies remained current, despite the lack of continually corroborative scientific evidence.

Oh well, another blinkered, dodgy, peer-reviewed paper. Who let this through? Oh, I forgot to mention the Guidelines. The first, ‘Proposed Guidelines for Critical Scientific Engagement by Members of the Public’ begins with this little preamble: If your goal is to contribute to a scientific conversation, then you need to follow certain rules. One of those rules is that scientific arguments are conducted in the scientific peer-reviewed literature. If you are unwilling to do so, these guidelines are of little value. Indeed so. Good luck, would-be contributor!

The second set is for scientists who might be approached by a member of the public seeking critical engagement. The Guidelines tell you to be careful — you might be approached by someone who is not in good faith, and wants to find errors in your work. Don’t help them!

And when you’ve finished both guidelines, you still don’t know what the authors think a ‘true sceptic’ is, or how he or she is to be distinguished from a ‘denialist’. Yet that is embodied in the title of the article.

Finally, the authors. The first two names will be familiar to readers of this website, and indeed to anyone interested in the ‘climate change’ issue: Stephan Lewandowsky, Michael E. Mann, Nicholas J. L. Brown and Harris Friedman. You will learn about the third and fourth by reading the article. They seem somewhat more sensible than the first two. Oh, there are 96 references, of which 22 are self-referenced articles, 16 of them by Lewandowsky alone. I may be wrong, but I could find just three references that were critical of the authors’ standpoint. Not exactly a review paper, for all its pretension.

And I find myself saying, yet again, this  awful, poorly argued, self-seeking paper has passed peer review? What have we come to in the journal world?

September 10, 2016 Posted by | Deception, Science and Pseudo-Science, Timeless or most popular | , | Leave a comment

Whats up with the Atlantic?

By Judith Curry | Climate Etc. | March 25, 2015

The Washington Post has this dramatic headline:  Global warming is now slowing down the circulation of the ocean with potentially dire consequences.

A new paper has been published that has the media talking about The Day After Tomorrow [link].  What is this new paper?

Exceptional twentieth-century slowdown in Atlantic Ocean overturning circulation

Stefan Rahmstorf, Jason E. Box, Georg Feulner, Michael E. Mann, Alexander Robinson, Scott Rutherford & Erik J. Schaffernicht

Abstract. Possible changes in Atlantic meridional overturning circulation (AMOC) provide a key source of uncertainty regarding future climate change. Maps of temperature trends over the twentieth century show a conspicuous region of cooling in the northern Atlantic. Here we present multiple lines of evidence suggesting that this cooling may be due to a reduction in the AMOC over the twentieth century and particularly after 1970. Since 1990 the AMOC seems to have partly recovered. This time evolution is consistently suggested by an AMOC index based on sea surface temperatures, by the hemispheric temperature difference, by coral-based proxies and by oceanic measurements. We discuss a possible contribution of the melting of the Greenland Ice Sheet to the slowdown. Using a multi-proxy temperature reconstruction for the AMOC index suggests that the AMOC weakness after 1975 is an unprecedented event in the past millennium (p > 0.99). Further melting of Greenland in the coming decades could contribute to further weakening of the AMOC.

Published in Nature Climate Change [link]; full manuscript available [here].

Stefan Rahmstorf has a post at RealClimate Whats going on in the North Atlantic?  Excerpt:

The North Atlantic between Newfoundland and Ireland is practically the only region of the world that has defied global warming and even cooled. Last winter there even was the coldest on record – while globally it was the hottest on record. Our recent study (Rahmstorf et al. 2015) attributes this to a weakening of the Gulf Stream System, which is apparently unique in the last thousand years.

Climate models have long predicted such a slowdown – both the current 5th and the previous 4th IPCC report call a slowdown in this century “very likely”, which means at least 90% probability. When emissions continue unabated (RCP8.5 scenario), the IPCC expects 12% to 54% decline by 2100. But the actual past evolution of the flow is difficult to reconstruct owing to the scarcity of direct measurements.

What is new is that we have used proxy reconstructions of large-scale surface temperature (Mann et al, 2009) previously published by one of us  that extend back to 900 AD to estimate the circulation (AMOC) intensity over the entire last 1100 years. This shows that despite the substantial uncertainties in the proxy reconstruction, the weakness of the flow after 1975 is unique in more than a thousand years, with at least 99 per cent probability. This strongly suggests that the weak overturning is not due to natural variability but rather a result of global warming.


Well, if there is anything I distrust more than climate model simulations of decadal to millennial scale ocean circulations and internal variability, it is Mannian proxy analysis of same. It seems like strip bark bristlecones and Tiljander sediments can tell us about Gulf Stream flow rates, as well as global temperatures. Remarkable.

So what do the actual ocean observations have to say? Anthony Watts has an extensive critique of the paper, pointing to a 2014 paper by oceanographer Thomas Rossby: On the long-term stability of Gulf Stream transport based on 20 years of direct measurements.  The title pretty much speaks for itself, but Rossby had this to say in an interview:

“The ADCP measures currents at very high accuracy, and so through the repeat measurements we take year after year, we have a very powerful tool by which to monitor the strength of the current,” said Rossby. “There are variations of the current over time that are natural — and yes, we need to understand these better — but we find absolutely no evidence that suggests that the Gulf Stream is slowing down.”

In 2010, NASA issued a press release NASA Study Finds Atlantic Conveyor Belt Not Slowing, citing a paper published by Josh Willis of JPL using measurements from ocean-observing satellites and profiling floats.  Punchline:

For now, however, there are no signs of a slowdown in the circulation. “The changes we’re seeing in overturning strength are probably part of a natural cycle,” said Willis. “The slight increase in overturning since 1993 coincides with a decades-long natural pattern of Atlantic heating and cooling.”

Pierre Gosselin cites additional critiques from German scientists. Notably:

Climate scientist Martin Visbeck of the GEOMAR Helmholtz Centre for Ocean Research in Kiel sees Rahmstorf’s assertion of the results critically: ‘The study’s focus on the sub-polar part of the Atlantic and the spectral analysis are interesting,’ he says. But there are other AMOC assessments that point to a completely other development. The paper does not offer any strong indication of the development of the AMOC during the past fifty years.”

So, who you gonna believe? Climate models and Mannian proxies, or direct and satellite observations of ocean circulation?

Atlantic Multidecadal Oscillation

What is going on the high latitudes of the North Atlantic can’t be understood without the context of the Atlantic Multidecadal Oscillation. If you are unfamiliar with the Atlantic Multidecadal Oscillation (AMO), see this summary. For reference, the AMO figures prominently in the stadium wave. While the method to define the AMO is still debated, here I show the canonical analyses from NOAA.

The monthly values of the AMO are shown below.


A blow up of the more recent data (through Dec 2014) is shown below:


While the AMO index shows substantial variability, there are multi-decadal periods when the index is predominantly positive (warm) and negative (cool). To the extend that past behavior is any guide to the future, the current warm phase is expected to transition to the cool phase sometime in the 2020’s. While the the 1995 transition was sharp, the transition to the next cool phase might be sharp, or it might ‘flicker’ for a few years or even a decade. We’ll have to see how this plays out.

There is some evidence that the warm phase of the AMO has peaked circa 2007, see the upper ocean heat content data shown below.


JC summary

What we are seeing in the high latitudes of the North Atlantic is natural variability, predominantly associated with the Atlantic Multidecadal Oscillation. Based upon observational analyses, there is no sign of a slowdown in the Gulf Stream or the Atlantic Meridional Overturning Circulation.

Now, I am very interested in the AMO, since it strongly influences Atlantic hurricanes, Arctic sea ice, and Greenland climate. We are already seeing a recovery of the Atlantic sector of the Arctic sea ice, and some hints of cooling in Greenland.

With regards to Atlantic hurricanes, Bill Gray and Phil Klotzbach are looking at a new definition of the AMO that they feel relates better to Atlantic hurricane activity [link], and they are seeing a transition to negative values.

And finally, the AMO does not act in isolation (e.g. the stadium wave); there are very interesting things going on in the Pacific also – perhaps a topic for a future post.

March 25, 2015 Posted by | Deception, Science and Pseudo-Science | , , , | 4 Comments

Hide the decline deja vu? Mann’s ‘little white line’ as ‘False Hope’ may actually be false hype

Watts Up With That? | March 24, 2014

Foreword by Anthony Watts 

An essay by Monckton of Brenchley follows, but I wanted to bring this graphic from Dr. Mann’s recent Scientific American article to attention first. In the infamous “hide the decline” episode revealed by Climategate surrounding the modern day ending portion of the “hockey stick”, Mann has been accused of using “Mike’s Nature Trick” to hide the decline in modern (proxy) temperatures by adding on the surface record. In this case, the little white line from his SciAm graphic shows how “the pause” is labeled a “faux pause”, (a little play on words) and how the pause is elevated above past surface temperatures.


Zoom of section of SciAm's graph from Dr. Mann. The 1°C line was added for reference.

Looking at the SciAm graphic (see zoom at right), something didn’t seem right, especially since there doesn’t seem to be any citation given for what the temperature dataset used was. And oddly, the graphic shows Mann’s little white line peaking significantly warmer that the 1998 super El Niño, and showing the current temperature equal to 1998, which doesn’t make any sense.

So, over  the weekend I asked Willis Eschenbach to use his “graph digitizer” tool (which he has used before) to turn Mann’s little white line into numerical data, and he happily obliged.

Here is the result when Mann’s little white line is compared and matched to two well known surface temperature anomaly datasets:



What is most interesting is that  Mann’s “white line” shows a notable difference during the “pause” from HadCRUT4 and GISS LOTI. Why would our modern era of “the pause” be the only place where a significant divergence exists? It’s like “hide the decline” deja vu.

The digitized Mann’s white line data is available here: Manns_white_line_digitized.(.xlsx)

As of this writing, we don’t know what dataset was used to create Mann’s white line of surface temperature anomaly, or the base period used. On the SciAm graphic it simply says “Source: Michael E. Mann” on the lower right.

It isn’t GISS land ocean temperature index (LOTI), that starts in 1880. And it doesn’t appear to be HadCRUT4 either. Maybe it is BEST but not using the data going back to 1750? But that isn’t likely either, since BEST pretty much matches the other datasets, and in Mann’s graphic above, which peaks out at above 1°C, none of those hit higher than 0.7°C. What’s up with that? … continue

March 25, 2014 Posted by | Deception, Science and Pseudo-Science, Timeless or most popular | , , | 1 Comment