Thursday, March 1, 2018

Myth: Judith Curry Fully and Accurately Represents Scientific Research

The outline for this post is as follows:
  1. The Myth and Its Flaw
  2. Context and Analysis
  3. Posts Providing Further Information and Analysis
  4. References

This is the "main version" version of this post, which means that this post lacks most of my references and citations. If you would like a more comprehensive version with all the references and citations, then please go to the "+References" version of this post.

References are cited as follows: "[#]", with "#" corresponding to the reference number given in the References section at the end of this post.

1.  The Myth and Its Flaw

Judith Curry is a prominent critic of mainstream science on anthropogenic (man-made) global warming (AGW)A number of parties champion her positions and cite her as an accurate source of climate science information, including the George C. Marshall Institute, the Global Warming Policy Foundation, The Daily Mail, The Washington Times, John Stossel, and the "lukewarmer" Matt Ridley. Curry's reliable representation of scientific research is the myth this blogpost addresses.

The myth's flaw: Curry's habitually distorts climate science in her blogspots, to the point that her own sources refute her position on greenhouse-gas-induced AGW and other topics. She often relies on unreliable, non-peer-reviewed sources, regurgitating their material without paying sufficient attention to more reputable sources. Curry also displays an inconsistent double standard when it comes to AGW vs. non-anthropogenic (natural) global warming. Her distortions conveniently align with her libertarian political ideology. She also continues to argue against various climate-related policies/regulations and to receive funding from the fossil fuel / energy industries.

2. Context and Analysis

Earth's atmosphere contains multiple layers. The layer closest to the Earth's surface air is known as the troposphere. Climate models predict that tropospheric warming in the tropics should increase with increasing height. The aforementioned tropical warming amplification is called the tropical tropospheric hot spot by many critics of mainstream climate science. Judith Curry, another critic of mainstream science on anthropogenic (human-made) global warming or AGW, spreads misinformation regarding the hot spot and other topics. 

For instance:

  1. Curry, starting in at least 2011, began claiming that Earth's temperature would remain largely flat for at least another decade, and likely for a couple of decades, in contrasts to the United Nations Intergovernmental Panel on Climate Change's (IPCC's) 2007 model-based warming projections. Earth then warmed at the rate predicted by the IPCC, debunking Curry's predictions. Yet she continues to avoid addressing evidence rebutting her forecasts.
  2. She misrepresents the accuracy of the IPCC's 1990 model-based projections of global warming.
  3. Curry claims greenhouse-gas-induced AGW began in the late 1970s, when it actually began at least 60 years earlier. In doing this, she leaves out about half of the anthropogenic warming effect, and about third of the total anthropogenic warming, while contradicting her published research that attributes the vast majority of the warming to anthropogenic greenhouse increases.
  4. She hosts a clear fabrication on her website, and she (or her website's moderators) remove comments that point out the fabrication.
  5. Curry falsely insinuates that the hot spot is a fingerprint of warming caused by greenhouse gases such as carbon dioxide (CO2).
  6. She casts doubt on the hot spot's existence, even though the sources she cites show the hot spot.
  7. Curry offers implausible arguments against the evidence-based scientific consensus that human release of greenhouse gases (especially CO2) caused most of the post-1950s global warming; I discuss this more in this blogpost. One of her arguments is as fallacious as saying one cannot know what caused a recent death, unless one explains another death from over 60 years ago. She even went so far as to insinuate that scientists exaggerated the impact of greenhouse gases in order to keep their jobs. Yet her published research entails that increased CO2 caused most of the industrial-era warming.
  8. Curry falsely claims that 1920s - 1950s warming is roughly on par with post-1950s warming, and that this undermines the claim that humans caused most of the post-1950s warming. To do this, she refers to older research from a particular author, while ignoring subsequent research from that author showing that humans caused most of the post-1950s temperature-induced changes in Arctic sea ice. She also cherry-picks older research on 1920s - 1950s Greenland ice melt, while ignoring subsequent, more comprehensive research that shows these Greenland trends are not on par with post-1970s Greenland ice melt.
  9. When speaking to the general public, she unfairly insinuates that scientists manipulated early 20th warming analyses, in order to minimize warming they found inconvenient. But in her peer-reviewed research, Curry lauds the adjustments to early 20th century warming analyses. So she tells one story when misleading non-experts, and a different story when writing for experts who are harder to mislead.
  10. Curry critiques corrections to a satellite-based analysis, yet she cites sources that implicitly support those corrections.
  11. Curry claims that satellite data is the best data we have, in contradiction to the evidence-based claims made by one of the satellite research teams she cites.
  12. She distorts a paper that compares model-based trends to satellite-based analyses.
  13. Curry distorts, and casts aspersions on, research from NOAA scientists, even though this research was supported by subsequent analyses and Curry's own sources undermined her distortions.
  14. She maligns a near-surface temperature trend analysis from Cowtan+Way, while evading the fact that a source she lauds provides support for Cowtan+Way's analysis.
  15. Curry uses a fossil-fuel-industry-funded fake expert to manufacture false doubt on well-evidenced, CO2-induced ocean acidification, including the ~30% increase in ocean acidity during the industrial-era.

I discuss these issues in more detail in the corresponding posts below:

  1. Section 2.1 of "Myth: The IPCC's 2007 ~0.2°C/decade Model-based Projection Failed and Judith Curry's Forecast was More Reliable", and "Myth: No Global Warming for Two Decades" (Also discussed in a Twitter thread [7])
  2. "Myth: The IPCC's 1990 Report Over-estimated Greenhouse-gas-induced Global Warming"
  3. Figure 8 of "Myth: The IPCC's 2007 ~0.2°C/decade Model-based Projection Failed and Judith Curry's Forecast was More Reliable"
  4. "On How the Operators of Judith Curry's Blog Respond to a Clear Fabrication"
  5. "Myth: The Tropospheric Hot Spot is a Fingerprint of CO2-induced Warming"
  6. Section 2.1 of "Myth: Evidence Supports Curry's Claims Regarding Satellite-based Analyses and the Hot Spot"
  7. Section 2.5 of "Myth: Attributing Warming to CO2 Involves the Fallaciously Inferring Causation from a Mere Correlation" (Also discussed in a Twitter thread [8])
  8. Section 2.5 of "Myth: Attributing Warming to CO2 Involves the Fallaciously Inferring Causation from a Mere Correlation"(Also discussed in a comment on Curry's blog [9] and a Twitter thread [8])
  9. "Myth: Karl et al. of the NOAA Misleadingly Altered Ocean Temperature Records to Increase Global Warming"
  10. Section 2.2 of "Myth: Evidence Supports Curry's Claims Regarding Satellite-based Analyses and the Hot Spot"
  11. Section 2.1 of "Myth: Evidence Supports Curry's Claims Regarding Satellite-based Analyses and the Hot Spot"
  12. "Myth: Santer et al. Show that Climate Models are Very Flawed"
  13. "Myth: Karl et al. of the NOAA Misleadingly Altered Ocean Temperature Records to Increase Global Warming"
  14. Section 2.2 of "Myth: Evidence Supports Curry's Claims Regarding Satellite-based Analyses and the Hot Spot"
  15. Section 2.1 and supplementary section 2.5 of "Myth: Ocean Acidification Requires that an Ocean Becomes an Acid"

These are not the only times Curry distorted science. For instance, a 2012 response paper rebutted basic mistakes Curry made in her interpretation of how scientists use climate models. The paper even needed need to correct Curry's (real or feigned) confusion on what the word "most" means. Scientists also critique the misleading testimony Curry gives to Congress on climate science and the paranoid rhetoric she resorts to. And when people critique Curry on her defense of nonsense sources, she neither adequately addresses the criticism, nor takes responsibility for the points she defends, nor pays sufficient attention to the published research on the topics she discusses.

Often Curry is unbelievably blatant in her attempts to evade criticism. A classic example occurred when Curry harshly and publicly reprimanded someone for pointing out plagiarism work critical of mainstream climate scientists. Yet the plagiarism charge was justified, to the point that the plagiarized article in question was retracted. Curry later claimed she had not investigated the plagiarism issue in detail, did not intend to, and asked that no further comment be allowed on the topic.

Scientists such as Ken Rice, Peter Jacobs, Victor Venema, James Annan, Grant Foster, Robert Way, Stephen Schneider, Michael Mann, Arthur Smith, and Gavin Schmidt have pointed out Curry's abuse of these types of tactics. Others have done so as well (including criticism from women, to whom Curry replies with personal attacks). For example, in response to Curry's claims regarding published papers, Schmidt noted:

"Absolutely untrue in all respects. No, really, have you even read these papers? [...] Judith, I implore you to do some work for yourself instead of just repeating things you read in blogs. (Hint, not everything on the Internet is reliable) [1]."

"In future I will simply assume you are a conduit for untrue statements rather than their originator. And if we are offering advice, might I suggest that you actually engage your critical faculties before demanding that others waste their time rebutting nonsense [2]."

Curry's August 19, 2017 blogpost nicely illustrates Curry's aforementioned tactics. In this blogpost, Curry repeats a headline from the blog WattsUpWithThat run by Anthony Watts. The headline states that a study showed that 20th century warm periods in China are not unprecedented in the context of the past 2000 years. Other non-peer-reviewed sources made this point, including JoAnne Nova's blog.

Nova's blog and WattsUpWithThat are two of the most popular AGW "skeptic" blogs. So by emphasizing the same point as Nova's blog and WattsUpWithThat, Curry repeated a popular and prominent point from the "skeptical" blogosphere. Of course, Curry, WattsUpWithThat, and JoAnne Nova conveniently left out the fact that the paper suggests that increases in greenhouse gases caused 20th century warming:

"This suggests that, before the 20th century, regional differences in global warming were driven by natural climate forcing [...]; whereas, global warming in the 20th century was driven by increased greenhouse gas volumes [...]. Thus, warming due to increased volumes of greenhouse gases generates a different climate signature from that caused by changes in solar radiation, as demonstrated by results based on an ECHO-G climate model simulation (Liu et al., 2013), and has led synchronized global warming throughout the 20th century, especially in the [northern hemisphere] [3, page 946]."

Mentioning this portion of the paper would interfere with the critique Curry, WattsUpWithThat, and other "skeptics" offer regarding the science on greenhouse-gas-driven AGW. So they all conveniently evaded that portion of the paper. This is not the first time that "skeptic" blogs distorted the studies they discuss; these distortions may result from the "skeptic" bloggers not actually reading the studies they cite.

There is no inherent problem with Curry (or anyone else) reading blogposts, as long as they pay sufficient attention to reputable, peer-reviewed scientific sources. Though peer review is not perfect, competent peer review helps prevent nonsense from being published, in contrast to the nonsense published on many denialist blogs. Many AGW denialists, AIDS denialists, young Earth creationists, and other science denialists evade this point by inventing paranoid conspiracy theories about peer review and by citing fake experts who's views contradict published evidence. Similarly, Curry opts for Watts' distortions of published research; she also recently opted for blog reviews over peer review, despite her previously criticizing the IPCC for using non-peer-reviewed sources. In sections 2.2 and 2.3 of "Myth: Evidence Supports Curry's Claims Regarding Satellite-based Analyses and the Hot Spot", I discuss another instance in which Curry went astray by relying on a blog article instead of peer-reviewed research.

To given another example: Curry promoted Murry Salby's claim that natural (non-anthropogenic, or not human-made) factors caused most of the observed industrial-era increase in atmospheric CO2 levels. Salby did not make his claims in a peer-reviewed publication, nor did Curry provide an evidence-based defense of Salby's position. This was in keeping with Curry's history of spreading the idea that natural factors caused the industrial-era increase in CO2. Curry also rejected a detailed rebuttal of Salby's claim, without explaining why she rejected the rebuttal, and she declined (citing time constraints) to read peer-reviewed publications providing evidence that natural factors acted as net uptakers, not net releasers, of CO2.

Yet Curry still insinuated that a politically-manufactured consensus explained why scientists accepted that anthropogenic factors caused the CO2 increased, as opposed to natural factors as Salby claimed. She insinuated this despite her inability to defend Salby's claims and her refusal to read peer-reviewed sources on this basic aspect of climate science (in section 2.8 of "Myth: Attributing Warming to CO2 Involves the Fallaciously Inferring Causation from a Mere Correlation", I cite evidence showing that natural factors acted as net uptakers of CO2 and that human caused most of the industrial-era increase in atmospheric CO2). So Curry used ideologically-charged evidence-free rhetoric to avoid addressing evidence against dubious claims she promoted, and to avoid peer-reviewed research rebutting those claims. 

And even when Curry might have read the peer-reviewed sources she discusses, she still distorts the sources in a way that fits the denialist/contrarian preferences of many of her blog's visitors. For instance, in her 2017 blogpost, Curry claimed that a paper showed that natural climate fluctuations caused half of the global warming over the past 135 years. The paper actually only said there was a >25% chance that this was the case.

So if Curry read the paper, then she was apparently fine with this ">25%" probability claim. But when it came to responding to evidence on man-made global warming, Curry objected to how "imprecise [4, page 1685]" the word "most" was, even though "most" represents a more precise probability than the >25% probability, since "most" means ">50%". Thus Curry claimed the precision for anthropogenic global warming was too low, while also accepting even less precision for non-anthropogenic (or natural) global warming. Curry therefore displays an inconsistent double standard when it comes to evidence for man-made climate change vs. evidence for non-man-made, natural climate change. This is not surprising, given other critiques of Curry's self-contradictory abuse of probabilistic reasoning.

And in the same 2017 blogpost, Curry summarized another paper as follows:

"Identification of the driving forces of climate change using the longest instrumental temperature record [link] Punchline: solar, El Nino [5]"

The paper does state that the Sun and El NiƱo were shorter-term drivers of climate change. But Curry left out the fact that the paper suggests that greenhouse gases (such as CO2) act as longer-term drivers of climate change. When this was pointed this out to Curry, she evaded the points she left out from the paper, much as she did in her discussions with Gavin Schmidt and others.

Thus Curry left out pertinent information on greenhouse-gas-induced global warming for at least two papers she cited in the same blogpost. Yet she conveniently found space in the same blogpost to cite a non-peer-reviewed press piece about how data on greenhouses gases might undermine intergovernmental responses to climate change:

"Dodgy greenhouse gas data threatens Paris accord [link] [5]"

So Curry found space in her blogpost to undermine public confidence in mitigating greenhouse gas emissions. But she conveniently did not find space in that same blogpost to accurately represent the scientific research she cites on the impact of greenhouse gases. She also continues to argue against various climate-related policies/regulations and to receive funding from the fossil fuel / energy industries. This might lead one to think Curry is a libertarian who distorts climate science in order to avoid policies she dislikes, especially since she admits to leaning libertarian (for more discussion on the relationship between political conservatism and responses to the science on AGW, see section 3.1 of "John Christy, Climate Models, and Long-term Tropospheric Warming"). If this is the case, then Curry would not be the only political conservative in this position.

Many (but not all) political conservatives distrust climate science research because they think this research could be used to support environmentalism, regulation, or other policies. This produces a negative correlation in the US between political conservatism vs. trusting climate scientists and accepting various scientific claims regarding climatology. These two correlations result in an ideologically-motivated controversy on AGW.

Fossil-fuel-industry-funded think tanks, the media, and other denialists maintain the controversy by manufacturing more false doubt about climate science. Yet Curry cites these same think tanks, media, and denialists as worth taking as seriously as peer-reviewed research. These think tanks and media outlets then, in turn, promote Curry's work. So Curry promotes sources that misinform many political conservatives on climate science, while these sources defend her. She also distorts peer-reviewed papers that could better inform these conservatives about greenhouse-gas-induced AGW, as shown by her discussion of the two aforementioned papers.

One might therefore suspect that Curry left out the papers' points on greenhouse gases, because the papers' support the mainstream science on CO2-driven AGW objected to by Curry, the thinks tanks (and other sources) she often cites and who cite her, and many of her politically conservative blog readers. Or maybe Curry did not bother to read the papers closely before commenting on them. One might also suspect that Curry distorted the paper on natural climate fluctuations for the same reasons.

Curry's example illustrate the dangers of solely relying on Internet critics (including me) for one's information on science; it always pays to read the peer-reviewed scientific literature, to ensure that Internet critics accurately represent what the scientific evidence shows and that they do not distort the evidence to support an ideologically-convenient position. As Curry noted in response to one of her critics:

"Read the literature and the IPCC [the IPCC is the United Nations' Intergovernmental Panel on Climate Change] [6]."

As a final note: Curry continues to misrepresent scientific research to downplay CO2-induced climate change, going up to at least March 2020. And to make matters even worse, even non-peer-reviewed denialist blogs like WattsUpWithThat offered more accurate representations than Curry. So she cannot even blame them this time around for the distortions she peddles. So Judith Curry likely learned nothing from her repeated history of misrepresenting peer-reviewed research.

Curry eventually admitted her misrepresentation of the research was a mistake. But that still leaves a major problem she failed to address: based on the research Curry advertised and misrepresented in January 2020, anthropogenic increases in CO2 caused more than 100% of the global warming from 1955 - 2005; i.e. other factors caused a cooling effect that partially offset the CO2-induced warming. And that is not even including the substantial warming effect from non-CO2 greenhouse gases humans produced. Thus the research Curry cites again undermines her attempts to manufacture false doubt about humans causing most of the post-1950s global warming.

3. Posts Providing Further Information and Analysis

4. References

  3. "Characteristics of temperature change in China over the last 2000 years and spatial patterns of dryness/wetness during cold and warm periods"
  4. "Comment on “Climate Science and the Uncertainty Monster” by J. A. Curry and P. J. Webster"
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