A FEW INCONVENIENT TRUTHS

Climate Audit

Posted by Stephen McIntyre

A few inconvenient truths

John A thought that it would be worthwhile to draw attention to some articles on scientific reaction to Al Gore’s film „An Inconvenient Truth“. and started this post. I have kept his links and quotations, but otherwise re-written this post.

I haven’t seen Al Gore’s film and may comment on it myself later. I suspect that the film uses the most lurid and sophomoric images available and invites equally sophomoric responses. I think that there are some valid issues, but these debates tend to get reduced to sound-bites.

John A cited the following articles and provided some quotes from them, which I discuss below:

„Scientists respond to Gore’s warning of climate catastrophe„, „The gods are laughing“ and „Global Warming fever„

Here’s one kind of issue that I think that it’s pointless to discuss:

Gore repeatedly labels carbon dioxide as „global warming pollution“ when, in reality, it is no more pollution than is oxygen. CO2 is plant food, an ingredient essential for photosynthesis without which Earth would be a lifeless, frozen ice ball. 

Both sides are trivializing the issue. It’s not obvious to me that any effects of higher CO2 so far have been adverse to humans, but I also think that the impact of 2xCO2 is a large and important issue, worth studying and understanding. I’m assuming that most readers of this site are interested in more nuanced analysis.

A next quotation from a Gore critic:

The hypothesis that human release of CO2 is a major contributor to global warming is just that — an unproven hypothesis, against which evidence is increasingly mounting.

In fact, the correlation between CO2 and temperature that Gore speaks about so confidently is simply non-existent over all meaningful time scales. U of O climate researcher Professor Jan Veizer demonstrated that, over geologic time, the two are not linked at all. Over the intermediate time scales Gore focuses on, the ice cores show that CO2 increases don’t precede, and therefore don’t cause, warming. Rather, they follow temperature rise — by as much as 800 years. 

Personally, I have only carried out detailed analysis of arguments which purport to show that the 1990s were the „warmest decade“ of the millennium. When I try to venture into other arguments and issues, I have far less knowledge. Extrapolating from the lack of due diligence in the hockey-stick arguments, I am concerned about the level of verification and due diligence in these other areas, but perhaps it’s different. On the argument of CO2 leading or lagging ice age changes, I don’t see that it gives much comfort to either side. My understanding of the evidence is that changes in dO18 levels lead changes in CO2 levels in ice cores; however modelers argue that changes in CO2 level are an important feedback which intensify the changes.

Next:

Even in the past century, the correlation is poor; the planet actually cooled between 1940 and 1980, when human emissions of CO2 were rising at the fastest rate in our history.

It would be worthwhlie pasing through the history of this issue. If you look back at material written in the late 1980s or 1990 – for example, the interesting text by Crowley and North – they attribute the seeming lack of response to natural variability. With the subsequent warming in the 1990s, everybody in this particular debate seems to have switched sides on natural variability. Sulphur dioxide emissions and aerosols have been invoked as an explanation. Here there don’t seem to be valid estimates of the forcing other than by difference, so it’s hard to see that anything very much is settled. The lack of a more monotonic response to CO2 increases does raise question marks for me, but no more than that.

Next:

Similarly, the fact that water vapour constitutes 95% of greenhouse gases by volume is conveniently ignored by Gore. 

I don’t get this point at all. So what? I think that there are important and interesting issues about negative feedbacks associated with water vapor, as well as the more publicized positive feedbacks. I don’t see the purpose of exchanging soundbites of this type.

Next:

While humanity’s three billion tonnes (gigatonnes, or GT) per year net contribution to the atmosphere’s CO2 load appears large on a human scale, it is actually less than half of 1% of the atmosphere’s total CO2 content (750-830 GT). The CO2 emissions of our civilization are also dwarfed by the 210 GT/year emissions of the gas from Earth’s oceans and land. Perhaps even more significant is the fact that the uncertainty in the measurement of atmospheric CO2 content is 80 GT — making three GT seem hardly worth mentioning.

This seems like a frivolous point expressed this way. Yes, human CO2 emissions are a small fraction of annual flux, but I don’t see that that has any relevance to the issue of the impact of CO2 build-up. The measurement issue also is a total red herring. I have no doubt that CO2 measurements are more than accurate enough for the purposes of this particular debate.

Next:

Scientists who actually work in these fields [of atmospheric physics] flatly contradict Gore. Take his allegations that extreme weather (EW) events will increase in frequency and severity as the world warms and that this is already happening. Former professor of climatology at the University of Winnipeg Dr. Tim Ball notes, „The theories that Gore supports indicate the greatest warming will be in polar regions. Therefore, the temperature contrast with warmer regions — the driver of extreme weather — will lessen and, with it, storm potential will lessen.“

If you have warmer oceans, it seems plausible to me that there will be more hurricanes, even if there is a somewhat lessened temperature contrast. I suspect that the temperature contrast would be sufficient. However, I think that there are real attribution issues. There seems to be evidence of very high solar activity in the 20th century and especially in the late 20th century. The attribution studies that I’ve sen, which attempt to allocate between solar and CO2, are very weak. In fact, Mann’s attribution arguments in MBH98, discussed about one month ago here, included outright falsehoods in his statistical claims – first identified in blogworld by Chefen, Jean S and myself.

In an emotional debate, I think that there’s an important role for analyzing individual arguments being relied upon. I’ve focused on the multiproxy studies and have come to the conclusion that all the hockey-stick studies are flawed and biased. De-constructing each individual study is very time-consuming. I view this exercise as not dissimilar to that of a pre-war analyst studying proxy evidence for WMD such as aluminum tubes. At the end of the day, an analyst is sometimes obliged to say that maybe an aluminum tube is just an aluminum tube. That does not mean that some other piece of evidence may not be valid – only that the aluminum tube wasn’t.

In response to the criticisms of the hockey stick, the main defence or excuse has been that the hockey stick doesn’t „matter“. The concern about 2xCO2 arises from basic physics and the HS could be wrong but still leave us with an important problem. In one sense, I agree. If the HS were wrong, 2xCO2 is still an issue. Then why did IPCC and governments feature the HS so much? I presume that it was for promotional purposes. I would be shocked if Al Gore didn’t rely on arguments of this type for promotional purposes and this is the type of thing that I will be looking for when I see the film rather than silly issues like measuring the amount of CO2 in the atmosphere.

1. Truth Is Inconvenient
   http://www.lewrockwell.com/orig6/giles2.html Atmospheric Physics is a growth industry but only for those that sing the proper tune and in the proper key: the proverbial sky is falling and only bold, massive government and inter-governmental regulation and expensive “investments” (paid for by the taxpayer) can save the world. Al Gore is a lifelong politician who has never held a job, the son of a politician, who has unfailingly played the role of Chicken Little (in a public policy frame of mind) his entire adult life. This movie is a just another shameless, self-promoting, dishonest and mendacious attempt at securing more taxpayers dollars which at best will squander billions on science without results (think star wars) or possibly a cruel lie that will lead to the death of millions through environmental mismanagement at its worst. Now that is an Inconvenient Truth.

Legates Op Ed

Posted by Stephen McIntyre

An Op Ed by David Legates of the University of Delaware in today’s National Post, entitled

Where’s the data?: Holding science to prospectus standards would stop climate researchers from launching misrepresentations like the ‘Hockey Stick’ By: David Legates

Tuesday, September 20, 2005
In June, the energy and commerce committee of the U.S. House of Representatives opened an investigation of a prominent scientific study and the circumstances under which it became the centrepiece of a report by the United Nations Intergovernmental Panel on Climate Change.

The investigation has many observers, including climate scientists themselves, up in arms. The Washington Post called the committee action a “witch hunt,” while others have compared it to the Spanish Inquisition. The American Geophysical Union and the American Meteorological Society have written a joint letter of protest, accusing the House energy committee of undermining science and attempting to intimidate its authors. Editors of prominent journals like Nature and Science have weighed in on even stronger terms.

Although critics contend the issue is about scientific freedom, the questions actually pertain to disclosure, due diligence and the need for access to publicly funded scientific data when public policy is at stake. In reality, the investigation is not only entirely proper, but long overdue.
The saga begins in 1998, when Michael Mann and colleagues published a graph in Nature that they argued represents the air temperature history of the Northern Hemisphere for the last 1,000 years. Owing to its shape, the curve is called the “Hockey Stick.” It shows a relatively constant air temperature (with a slight decline) from A.D. 1000 until the late 1800s. But over the last century, the air temperature dramatically increases by about 0.6C, which, the authors and believers assert, proves that humans are indeed responsible for virtually all of the climate change of the past millennium. It was the Hockey Stick that originated the sound bite declaring 1998 to be the “warmest year” of the millennium and the 1990s the “warmest decade” — a sound bite used by the Canadian government in making the case for adopting the Kyoto Protocol.

The Hockey Stick stands in stark contrast to a long-held view, amply supported by work of other researchers, that the last 1,000 years were characterized by a warm beginning (the Medieval Warm Period), a rapid cooling around A.D. 1500 (the Little Ice Age), and a latter-day recovery from this cooler period. The Hockey Stick became entwined with energy policy when the IPCC replaced this traditional view and featured the Hockey Stick prominently in its 2001 assessment of climate science — in a section written by Mann himself. It surprises many to learn that the IPCC assessment often is written by scientists who dominate the debate about specific issues.
Clearly such scientists have axes to grind and, in Mann’s case, he used the IPCC as a forum to promote his own research. Other IPCC authors admonished Mann to include other, less Hockey Stick-like representations in his assessment. They were ignored in the final report, however, and, owing to the influence that the IPCC reports carry, the Hockey Stick became a public icon, enthusiastically promoted by supporters of the hypothesis of greenhouse warming.

The statistical methods used by Mann and his colleagues have been the subject of much recent scrutiny. Based on our own research and a detailed comparison with the published evidence, Willie Soon and I raised the spectre of flawed statistics in the Hockey Stick when we testified with Mann at a U.S. Senate committee hearing in 2003. Subsequently, two Canadians with strong statistical training — energy analyst Stephen McIntyre and economist Ross McKitrick — attempted to replicate Mann’s results using the data he had supplied them. They found a number of errors, improper calculations, and misrepresentations of methodology. In the refereed literature, other researchers have expressed concerns about and demonstrated problems with the Hockey Stick.

The McIntyre and McKitrick study led to a corrigendum in Nature, where Mann and his colleagues admitted to various inaccuracies in their original description of their data and analysis. Nature took the extremely unusual step of requiring Mann and co-authors to provide a new archive of data and a new verbal description of their methodology. But even with this revised release, key aspects of the Hockey Stick remain impossible to replicate — and replication is a hallmark of scientific inquiry. Mann continues to refuse requests for full disclosure, telling The Wall Street Journal that to do so would amount to “giving in to intimidation.”

Despite the importance of the Hockey Stick for climate policy and the repudiation of scientific ethics implicit in Mann’s statement, there was no reaction to The Wall Street Journal article by the U.S. National Research Council or any learned societies and virtually no shock or surprise from climate scientists themselves. However, these extraordinary and injudicious remarks by Mann did attract the attention of the U.S. House energy and commerce committee, an important committee with broad investigatory powers, which carried out hearings on Enron, for example.

But the issue here goes beyond data and methodological documentation. The energy and commerce committee asked Mann and colleagues about the withholding (from their analysis) of vital statistical information that was highly adverse to their claims. This amounts to selectively choosing data to support their position and ignoring data that refutes it. But the academic community has misconstrued the intent of the committee by largely assuming it is attempting to decide nuances of statistical interpretation. In fact, the committee is on much more familiar turf than the learned societies have appreciated: Their request regards issues of disclosure, framed in the language of securities legislation — terminology with which the House committee is completely familiar. If science were subject to prospectus standards, withholding of such information would not have been permissible.

“Informational hoarding” is being challenged. Some academic journals now require publication of all data and computer code along with the article itself. The U.S. National Institutes of Health, which funds many billions of dollars worth of medical research, has mandated that large grants are conditional on data sharing. Other federal agencies are now beginning to consider NIH’s lead to provide verification of important findings.

Since the House energy committee is responsible for energy policy, it has every right to demand additional scrutiny for studies upon which energy policy is being made. Failing to disclose data or methods is not an acceptable option when energy policy is at stake. Moreover, since Mann was the author of the section of the IPCC that touted his own research before others had the opportunity to critically re-examine his work, serious questions must be raised about conflicts of interest within the IPCC and how it came to promote speculative findings that had not been independently evaluated and which since have been shown to be flawed.

The outrage expressed by the AGU, AMS and other scientific societies is hypocritical. Funding for climate science amounts to several billion dollars a year, but these groups strongly protest the accountability that goes with it. Both the AGU and AMS have adopted statements calling on the United States to change its energy policies in light of the climate-change issue. Yet while they insist that this research be the basis for policy decisions, they object to its scrutiny by policymakers.

In this instance, the House energy committee has uncovered a real problem in science — one that extends far beyond the climate-change issue. Scientists must demand that results and conclusions stand up to independent verification. Yet since the climate-change community has failed to impose such standards on itself, it cannot be surprised if legislators have opted to do the job for them.
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Dr. David Legates is an associate professor and director of the Center for Climatic Research at the University of Delaware in Newark, Del.