Factcheck: Scientists pour cold water on claims of ‘journal bias’ by author of wildfires study

A researcher who claimed his wildfire study was only published in a prominent journal because he “left out the full truth” has faced widespread criticism from other scientists and the journal’s editor.

The study, led by US scientist Dr Patrick Brown and published in Nature last week, found that rising global temperatures are increasing the risk of “extreme daily wildfire growth” in California. 

However, a mere six days later, Brown penned an article online claiming that the research was only published because he “stuck to a narrative I knew the editors would like” regarding the impacts of climate change.

Right-leaning media in the UK and US amplified his claims that he omitted other key contributors to wildfire risk because it would “dilute” the story that journals “wanted to tell”.

However, other scientists were quick to point out that the study’s reviewers had indeed recommended that these other factors were considered.

In addition, Brown and his co-authors themselves had argued in their response to the peer reviewers that including the other factors was “very difficult” and that was “precisely why” they had chosen to focus on “the much cleaner but more narrow question of what the influence of warming alone”.

In a statement, Nature’s editor-in-chief Dr Magdalena Skipper accused Brown of “poor research practices” that were “not in line with the standards we set for our journal”.

One study co-author told Carbon Brief that Brown’s comments “took me by surprise” and that “I don’t think he has much evidence to support his strong claims that editors and reviewers are biased”.

Meanwhile, other climate scientists described Brown’s actions as “monumentally unethical” and “very, very weird behaviour indeed”.

Here, Carbon Brief explains Brown’s claims – and the response to them.

• What did the wildfires study say?
• What did Patrick Brown claim?
• What did the study’s peer-review comments show?
• How did Nature respond?
• Have the study’s co-authors responded?
• How did other scientists respond?
• How did the media react?

What did the wildfires study say?

Dr Patrick Brown is currently co-director of the climate and energy team at the Breakthrough Institute – a controversial thinktank in California which “promotes technological solutions to environmental and human development challenges”. He also works as a lecturer in the energy, policy and climate programme at Johns Hopkins University. 

The wildfire research, published by the peer-reviewed journal Nature on Wednesday 30 August, was initially conducted when Brown was an assistant professor at San José State University. According to his personal website, Brown still holds the position of visiting research professor at the university’s Wildfire Interdisciplinary Research Centre.

The paper has seven other authors, although co-author and meteorologist Holt Hanley told Brown in an interview posted on Twitter that “I would say the large majority of the work was put together by you”.

The study uses the “storyline approach” – a method used in extreme event attribution research – to assess the impact of temperature change on wildfire growth in California.

In the interview, Brown explained to Hanley that, when using the storyline approach, scientists “take a weather event or sequence of weather events and place it in different background climate states”. 

The study first uses machine learning to quantify the relationships between temperature, aridity and the risk of “extreme daily wildfire growth” in California. 

Once those relationships are established, the authors assess how fires would spread in a warmer climate, while other conditions – such as wind, precipitation and absolute humidity – remain constant.

Using this method, the study estimates how historical fires over 2003-20 would change under different temperature and aridity conditions. It finds that human-caused warming has enhanced the expected frequency of extreme daily wildfire growth by 25%, on average, compared with pre-industrial conditions – although for some specific fires there was no change and for other fires there was an enhancement of more than 400%.

The authors estimate that, by the end of the century, in a low future warming scenario, the frequency of “extreme fire growth events” will be 59% higher than in a pre-industrial climate. The frequency increases to 172% higher by the end of the century under a very high warming scenario, they add.

The study was circulated to journalists a few days ahead of its publication under embargo. This practice is common among larger journals. The Nature press team shared a short summary of the article, suggesting that they believed the article would receive media attention. The summary concludes:

“The authors suggest that while temperature is one of many variables that influence wildfire behaviour, it is the variable most closely related to increasing greenhouse gas concentrations. The authors also suggest their calculations may result in conservative estimates of changes in risk, because several variables held constant in the model, like precipitation, wind and absolute humidity, may change in the future and exacerbate the enhanced risk due to warming.”

The study was covered by the Los Angeles Times and the newswire Agence France-Presse – the latter of which was reposted by many other smaller outlets. 

What did Patrick Brown claim?

On Tuesday 5 September, six days after his paper had been released, Brown published an article in the Free Press (a US-based website known for promoting “culture-war” issues) in which he claimed he had “left out the full truth” of his research in order to get it published in a high-profile peer-reviewed journal. 

The article was subsequently reposted as a comment piece by the New York Post, a US right-leaning tabloid, with the headline: “As a scientist, I’m not allowed to tell the full truth about climate change.”

His study focused “exclusively on how climate change has affected extreme wildfire behaviour”, wrote Brown, adding that “I knew not to try to quantify key aspects other than climate change in my research because it would dilute the story that prestigious journals like Nature and its rival, Science, want to tell”.

He argued that the editors of prominent journals “have made it abundantly clear, both by what they publish and what they reject, that they want climate papers that support certain pre-approved narratives – even when those narratives come at the expense of broader knowledge for society”.  

There is a “tremendous premium placed on publishing in journals like Nature and Science”, said Brown and “it’s also become extraordinarily more competitive” to get published as the number of researchers has “skyrocketed”. As a result, Brown said, “savvy researchers tailor their studies to maximise the likelihood that their work is accepted”. 

It is, therefore, necessary to ensure the research “support[s] the mainstream narrative”, he claimed:

“[N]amely, that the effects of climate change are both pervasive and catastrophic and that the primary way to deal with them is not by employing practical adaptation measures like stronger, more resilient infrastructure, better zoning and building codes, more air conditioning – or, in the case of wildfires, better forest management or undergrounding power lines – but through policies like the Inflation Reduction Act, aimed at reducing greenhouse gas emissions.”

As a result, Brown said he “focused narrowly on the influence of climate change on extreme wildfire behaviour”, adding: 

“Make no mistake: that influence is very real. But there are also other factors that can be just as or more important, such as poor forest management and the increasing number of people who start wildfires either accidentally or purposely.”

Brown said he “didn’t bother to study the influence of these other obviously relevant factors”, noting:

“Did I know that including them would make for a more realistic and useful analysis? I did. But I also knew that it would detract from the clean narrative centred on the negative impact of climate change and, thus, decrease the odds that the paper would pass muster with Nature’s editors and reviewers.”

(Brown noted here that he produced the study with seven other authors. However, he has subsequently stated on Twitter that the “all the decisions” to “mould” the way the research was presented to Nature “were made 100% by me and my co-authors bear no responsibility whatsoever”. Carbon Brief has contacted the co-authors for comment – see below.)

Brown also argued that, in order to be published, the research should “ignore – or at least downplay – practical actions that can counter the impact of climate change” and “be sure to focus on metrics that will generate the most eye-popping numbers”.

Not following this “formula” had seen Brown’s previous papers “rejected out of hand by the editors of distinguished journals” and he had instead needed “to settle for less prestigious outlets” – pointing to a 2020 study of his in the megajournal Plos One.

For the Nature study, the result was research that was “less useful than it could have been”, wrote Brown:

“I sacrificed contributing the most valuable knowledge for society in order for the research to be compatible with the confirmation bias of the editors and reviewers of the journals I was targeting.”

Nonetheless, Brown said in an accompanying thread on Twitter that he was “very proud of this research overall”. He also published a personal blog covering similar points.

What did the study’s peer-review comments show?

All research papers in credible academic journals go through some form of “peer review”. This process sees two or three scientists not involved in the study – but with appropriate expertise – offering their assessment of the work, often anonymously. They will recommend whether the paper should or should not be published, as well as offering suggestions for improvement.

Nature published the peer-review comments for Dr Brown’s paper alongside the study – a practice it has been offering since 2020.

There are three reviewers for the paper and author “rebuttals” to their comments are also included in the document.

Their comments, taken together, severely undermine Brown’s claims that he was encouraged to support what he described as the journal’s “pre-approved narratives”.

Two of the three reviewers said they could not recommend the paper for publication in its initial form, with the third reviewer providing comments, but no specific recommendation.

The two reviewers that recommended rejection both highlighted the limited scope of the study. Reviewer 1 noted that “a concern is the use of wildfire growth as the key variable”, adding:

“As the authors acknowledge there are numerous factors that play a confounding role in wildfire growth that are not directly accounted for in this study…Vegetation type (fuel), ignitions (lightning and people), fire management activities (direct and indirect suppression, prescribed fire, policies such as fire bans and forest closures) and fire load.”

Reviewer 3 was concerned that “the climate change scenario only includes temperature as input for the modified climate”, adding that “changes in atmospheric humidity would also be highly relevant”.

In a lengthy response, the authors wrote that “we agree that climatic variables other than temperature are important for projecting changes in wildfire risk”, adding: 

“In addition to absolute atmospheric humidity, other important variables include changes in precipitation, wind patterns, vegetation, snowpack, ignitions, antecedent fire activity, etc. Not to mention factors like changes in human population distribution, fuel breaks, land use, ignition patterns, firefighting tactics, forest management strategies and long-term buildup of fuels.”

However, “accounting for changes in all of these variables and their potential interactions simultaneously is very difficult”, they said:

“This is precisely why we chose to use a methodology that addresses the much cleaner but more narrow question of what the influence of warming alone is on the risk of extreme daily wildfire growth.”

They added:

“We believe that studying the influence of warming in isolation is valuable because temperature is the variable in the wildfire behaviour triangle…that is by far the most directly related to increasing greenhouse gas concentrations and, thus, the most well-constrained in future projections. There is no consensus on even the expected direction of the change of many of the other relevant variables.”

When these points were raised to Brown on Twitter, he responded that “the point here is that focusing exclusively on the climate change variable (temperature and, yes, acknowledging other variables but holding them constant) is what makes the study more likely to be publishable in a high-impact journal”.

He added:

“It would be MUCH more difficult to take any one of the other moving parts, study it in isolation, and get that into a high-impact journal.”

(Brown has also posted further comments in a piece on the Breakthrough Institute’s website where he argues that “nowhere in the peer-review process did reviewers challenge the usefulness of focusing solely on the impact of climate change when projecting long-term changes in wildfire behaviour”.)

However, in an interview conducted with study co-author and meteorologist Holt Hanley the day after the paper was published, Brown – adopting a very different tone – noted he considers the study as “step one” of ongoing research: 

“We did isolate the impact of temperature on – in this case – the risk of extreme [wildfire] growth…And, in that sense, we’re not looking at the relative influence of temperature change versus other important contributions like changes in ignition patterns and changes in fuel characteristics in particular. But, in our current phase of the research, we are bringing those in.” 

Full interview with @PatrickTBrown31 about our paper that was just published in Nature:

Climate Warming Increases Extreme Daily Wildfire Growth Risk in California#climate #wildfire #california #CAwx pic.twitter.com/8HPG4KeyLe

— Holt Hanley (@HoltHanley) August 31, 2023

How did Nature respond?

In a statement issued to Carbon Brief, as well as other media outlets, Nature’s editor-in-chief Dr Magdalena Skipper said the journal is “carefully considering the implications of [Brown’s] stated actions” which “reflect poor research practices [by the authors] and are not in line with the standards we set for our journal”.

Nature has an “expectation” that researchers use the “most appropriate” data and methods in their work, including “all key facts and results that are relevant to the main conclusions of a paper”, Skipper said. For researchers to deliberately not do this is, “at best, highly irresponsible”, she warned.

She also addressed the issue of peer-review comments:

“I note that the issue of the lack of inclusion of variables other than climate change was highlighted during the peer-review process, but the authors themselves argued against including it.”

Responding on Twitter, Brown said this was “not really true”, arguing that “a reviewer asked us about accounting for another climate variable (absolute humidity) and I voluntarily brought up other non-climatic factors in my response”. Other scientists on Twitter replied to point out that one of the reviewers had, indeed, raised non-climate factors. 

Skipper’s statement continued:

“When it comes to science, Nature does not have a preferred narrative. Nature editors make decisions about what to publish based solely on whether research meets our criteria for publication: original scientific research (where conclusions are sufficiently supported by the available evidence), of outstanding scientific importance, which reaches a conclusion of interest to a multidisciplinary readership.”

To conclude, Skipper gave three examples of recent publications in Nature that “do not follow the purported editorial biases alleged by Brown”.

She pointed to a study that finds the effect of marine heatwaves on bottom-dwelling fish are “often minimal”. Another article finds that the decline in the Amazon carbon sink is mainly due to a reduction in law enforcement, rather than changes in the climate.

And a “world view” paper on the factors that contribute to wildfire spread through communities discusses the built environment in fire-prone regions, such as roof materials, cladding types and the sizes and locations of windows.

In his response on Twitter, Brown said “of course there are counterexamples”, adding that “my point is not that it is impossible to publish high-impact papers that deviate from the formula I describe, but that it is much harder”.

In subsequent comments to Agence France-Presse climate journalist Roland Lloyd Parry, Skipper said she was “completely baffled” by Brown’s claim that he chose the results to fit a specific narrative. She said:

“If a researcher provides compelling, convincing, robust evidence that goes against a consensus, that study actually becomes of special interest to us – that’s how science progresses.”

With Brown’s paper, Nature was “persuaded” that a paper with a focus on climate “was of value to the research community because of the contribution made by the quantification (of climate impacts)”, Skipper added.

Have the study’s co-authors responded?

In its reporting of the story, E&E News noted that “it’s not clear if any of his co-authors knew about Brown’s plans” to make his claims once the paper was published.

It added that the co-authors include a number of “recent graduates and early-career scientists” and that none of them had yet responded to requests for comment.

But one senior co-author, Prof Steven Davis, a professor of Earth system science at the University of California, Irvine, has now spoken to Carbon Brief.

He says that Brown “may have made decisions that he thought would help the paper be published, but we don’t know whether a different paper would have been rejected”. He adds: 

“I don’t think he has much evidence to support his strong claims that editors and reviewers are biased.”

Davis says that he “wasn’t involved in strategic decisions to exclude factors from the study” and that Brown’s subsequent claims “took me by surprise”. 

He notes that “keeping the focus narrow is often important to making a project or scientific analysis tractable” and that he “wouldn’t call that ‘leaving out truth’ unless it was intended to mislead”. This, he notes, was “certainly not my goal”.

In a newly published interview with Heatmap, Brown told journalist Robinson Meyer that he gave some of the co-authors “a verbal heads up”, but “they did not see” his Free Press article before publication. He added:

“I wrote the paper, I did the entire analysis, and this is my thing in terms of the opinion piece as well.”

The authors of the original study have since written a letter to Nature in which they note that “as co-authors of the study, none of the rest of us was aware of [Brown’s] perspective, nor do we share it”.

How did other scientists respond?

Brown has been widely criticised by other scientists, both for the content of his claims and the manner in which he has aired them.

Dr Gavin Schmidt, director of the NASA Goddard Institute for Space Studies, told E&E News (see below) that Brown’s actions were “monumentally unethical”. 

Over decades of research in the field, Schmidt said he could not remember another author treating publication as a “game”, E&E News reported. Schmidt also said that Brown censored himself rather than being told his paper would not be published if he broadened his research, noting:

“He’s whistleblowing on himself – he did all of this…Nobody did anything to him.”

Prof Lisa Schipper, professor of development geography at the University of Bonn and Carbon Brief contributing editor, described Browns’ actions as “very, very weird behaviour indeed”.

On his blog, Prof Ken Rice, professor of computational astrophysics at the University of Edinburgh, noted that the study’s peer-review comments suggest that “at least one of the reviewers highlighted the nuances that Patrick claimed would prevent this paper from being published”. He continued:

“Not only did the authors’ response claim that their narrow framing was appropriate, this also doesn’t appear consistent with the suggestion that only certain narratives are acceptable to this scientific community.”

Several scientists also queried whether Brown’s co-authors were aware he was going to highlight his concerns about publishing in Nature after the paper came out. 

Schmidt added in a tweet that “there is no evidence whatsoever that Nature applied any improper pressure on Brown, but rather lots of evidence that he was less than honest or transparent [with] the journal or co-authors”.

(As mentioned earlier, Brown said in response that the decisions “were made 100% by me and my co-authors bear no responsibility whatsoever”.)

How did the media react?

Right-leaning outlets in the US and UK, which frequently promote climate-sceptic views and talking points, were quick to leap on Brown’s claims in the days following his article in the Free Press. 

The story made the frontpage of the UK’s Daily Telegraph on 6 September under the headline: “Climate change expert overhyped his findings.” US outlets, including Fox News and the Daily Caller, also ran the story under similar headlines.

GB News interpreted Brown’s comments as a warning that “research is CENSORED with ‘certain narratives’ deliberately shunned by academic journals”.

And the Mail titles published a series of articles. The first, in MailOnline on 5 September, said that Brown deliberately “omitted key fact[s]” to ensure that “woke” journal editors would publish his work. A subsequent article focused on Skipper’s response, before a third article in the Daily Mail’s print edition again reported on Brown’s original claims.

The Times led its coverage of the story on 8 September by noting Skipper’s rebuke, including quotes from the peer reviewers of the study.

A Sun article quoted Craig MacKinlay, the Conservative MP who leads the net-zero scrutiny group and has links to the climate-sceptic lobby group known as the Global Warming Policy Foundation. He said:

“There are many eminent voices across the spectrum of climate science, from scepticism to full adherence to the new religion. Scientific study in this area has diminished to making the most hyperbolic claims. I hold a science degree and my training was one of reaching a conclusion after full analysis and after following evidence, not writing the conclusion and then selectively using data to make it fit, ignoring anything inconvenient. We need honesty if we are to spend multiple trillions of pounds, change the way we’re expected to live and reduce our freedom on the net-zero pathway.”

The Daily Telegraph gave space on its comment pages to climate-sceptic commentator Matt Ridley, who said the incident shows that “the public isn’t being told the full truth about climate change”. Ridley claimed that Brown had “blown the whistle on an open secret about climate science: it’s biased in favour of alarmism”.

In the US, E&E News published a piece under the headline: “A scientist manipulated climate data. Conservative media celebrated.” The article said Brown was “hailed as a whistleblower by some conservative media outlets”, also noting the rebuke that Brown has since received from the scientific community. 

Writing on Twitter, Richard Black, a senior associate of the Energy and Climate Intelligence Unit and a former BBC environment correspondent, dismissed Brown’s claims that scientific journals reject papers that “don’t fit the climate change narrative”as an “ancient canard”. He said that he investigated this claim for BBC News in 2007 and “found nothing”.

“No, climate scientists aren’t being forced to exaggerate,” wrote Bloomberg columnist Mark Gongloff, in an opinion article on 8 September. “It reads like a climate denier’s dream come true,” Gongloff writes. However, he says that Brown’s claim “doesn’t add up”.

In contrast, the Times uncritically republished Brown’s original article for the Free Press on 9 September as its “weekend essay”. It also published an accompanying editorial stating that “these [journal] tactics lead to work that is deceptive and neglects promising lines of inquiry for fear of challenging consensus”.

On 11 September, the Times published a letter from Bob Ward, policy director at the Grantham Research Institute on Climate Change and the Environment, in which he scolds the Times:

“It was deeply ironic you chose that day [when the UK recorded its hottest September day on record] to publish a leading article alleging that scientific journals were ‘unwilling to consider research which downplays the scale of climate change’, citing an article by Dr Patrick Brown in which he made several inaccurate claims about current publication practices.”

On the same day, the Washington Post quoted Brown, responding to some of what the newspaper calls the “uproar” following his initial Free Press article. The outlet said that “Brown and some of his colleagues at the Breakthrough Institute worry that focusing narrowly on climate might ignore opportunities to adapt to changing temperatures”. Brown told the newspaper:

“I do think there is a taboo against studying increases in resilience to climate…That is thought to undermine the motivation for greenhouse gas emissions reductions.”

And, the following day, the Los Angeles Times quoted Prof Neil Lareau, assistant professor of atmospheric science at University of Nevada-Reno, who warned the episode was likely to fuel climate change denial conspiracies for decades. He said:

“I don’t think that’s Dr Brown’s intent…I kind of trust that he’s probably coming from a place with some level of frustration about the scientific publication process, and it’s an imperfect process. But frankly, it’s the best system that we have.”