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The battle for climate science and policy past—and why it matters

Roger Pielke Jr. delivers a scathing indictment of the climate science establishment, arguing that the field is clinging to discredited future scenarios not because the data demands it, but because admitting the error would undermine two decades of policy advocacy. The piece is notable for its specific historical pinpointing of 2017 as the moment the community should have pivoted, yet chose to double down instead. For busy leaders tracking energy transitions, the implication is stark: the models guiding trillions in investment may be built on a foundation of systematic error regarding fossil fuel production.

The Orwellian Turn

Pielke frames the recent COP30 agreement in Belém not as a diplomatic victory, but as a formalization of historical revisionism. He points to the agreement's claim that the world has already "bent the emission curve" and moved from a 4°C trajectory to a 2.3–2.5°C range as a dangerous distortion. "Today, I ask and answer — When should the climate community have first recognized that its projections of future climate change were based on flawed scenarios and taken action to correct course? The answer, in short, is 2017," Pielke writes. This rhetorical question forces a reckoning with the timeline of scientific knowledge versus institutional inertia.

The battle for climate science and policy past—and why it matters

The core of the argument rests on a 2017 paper by Justin Ritchie and Hadi Dowlatabadi, which Pielke describes as the "seminal" work that exposed the flaw. He notes that the paper found the scenarios underpinning IPCC assessments relied on a "systematic error in fossil production outlooks." Specifically, the models assumed coal consumption would skyrocket, a trajectory that contradicted geological realities and historical trends. Pielke argues that this blind spot distorted uncertainty ranges for primary energy since the 1970s and continues to plague the Shared Socioeconomic Pathways (SSP) framework used today. The failure to act on this finding is, in his view, a deliberate choice to preserve a narrative of impending catastrophe that justifies current policy paths.

"If scenarios are flawed — or more generously, just out of date — then projective climate science will also be flawed or out-of-date."

Critics might argue that scientific models are inherently uncertain and that retaining high-emission scenarios is a necessary precautionary measure, regardless of their statistical likelihood. Pielke counters this by suggesting that the continued use of these scenarios is not about caution, but about protecting the political momentum of the last decade.

The Rehabilitation of a Flawed Narrative

The commentary shifts to the 2020 intervention by Zeke Hausfather and Glen Peters, who Pielke claims "put a spin" on the Ritchie and Dowlatabadi findings. Rather than accepting the conclusion that high-emission scenarios were fundamentally implausible due to flawed energy assumptions, Hausfather and Peters reframed them as "unlikely worst cases." Pielke writes, "The broader climate community found the Hausfather and Peters spin on Ritchie and Dowlatabadi to be much preferrable than the original, devastating analysis." This preference, he suggests, allowed the community to ignore the structural flaws in the models while maintaining the urgency of the threat.

The author highlights a stark divergence in how this work has been treated. While Ritchie and Dowlatabadi were largely ignored for years, the reinterpretation by Hausfather and Peters has been cited over 1,300 times. Pielke notes that Hausfather continues to defend the scenario's utility, claiming that "the world is in a very different place" and that high-end scenarios are now clearly labeled as non-typical. However, Pielke sees this as a half-measure that fails to address the root cause: the models were wrong from the start, not just outdated by recent policy success. He points out that nearly 10,000 studies published in 2025 alone are still utilizing these falsified scenarios. "What a waste of effort and resources," he asserts, emphasizing the opportunity cost of relying on bad data.

"Thus, the battle over climate science and policy past is also a battle over the future of climate science and policy, as well as who and whose ideas lead the way."

This section reveals the high stakes of the debate. If the scenarios were flawed ab initio, then the perceived success of climate policy is an illusion, and entirely new approaches to decarbonization are required. Pielke argues that the community is currently stuck in a defensive posture, unwilling to admit that the "business-as-usual" path never existed in the first place.

The Cost of Denial

Pielke concludes by warning that the rehabilitation of these discredited scenarios will only intensify. He contrasts the views of Hausfather, who sees the shift away from high emissions as proof of policy success, with the work of Peters, who is now questioning the statistical validity of the model ensembles themselves. Peters, in recent work with Ida Sognnaes, suggests that the IPCC's use of database statistics may mean that targets are based on "idiosyncratic model or study assumptions" rather than a true distribution of futures. Pielke uses this to underscore that the problem is not just one scenario, but the entire methodological framework.

He argues that the refusal to correct course is a form of institutional self-preservation. "Some deny that these scenarios were ever flawed. Instead, they argue, it is climate advocacy and climate policy that has rendered these previously accurate scenarios obsolete," Pielke writes. This framing suggests that the scientific community is prioritizing political utility over empirical accuracy. The implication is that until the field admits the scenarios were fundamentally broken, the resulting policies will be misaligned with the actual energy transition already underway.

Bottom Line

Pielke's strongest argument is the evidence that the scientific community actively chose to reinterpret flawed data rather than correct it, prioritizing policy narratives over empirical truth. His biggest vulnerability lies in the assumption that admitting these errors would not destabilize the political consensus needed for climate action, a risk the establishment is likely unwilling to take. Readers should watch for how the next IPCC assessment cycle addresses the statistical validity of these ensembles, as the pressure to abandon the RCP8.5 and SSP5 frameworks is now impossible to ignore.

"The out-dated extreme scenarios should still be used, they argue, as a warning not to return to our bad old ways. However, if the scenarios were fundamentally flawed from the beginning, that would mean that climate advocacy and policy have actually accomplished very little, and that new and different approaches to decarbonization are needed."

Deep Dives

Explore these related deep dives:

  • Representative Concentration Pathway

    The article centers on RCP8.5 and its validity as a climate scenario. Understanding what Representative Concentration Pathways are, how they were developed, and their role in IPCC assessments provides essential context for the debate about whether RCP8.5 represents a plausible future or an implausible worst case.

  • Shared Socioeconomic Pathways

    The article discusses SSP5-RCP8.5 and SSP1-Sustainability extensively. Shared Socioeconomic Pathways are the framework that replaced earlier SRES scenarios and combine with RCPs to create the scenarios used in modern climate research. Understanding SSPs is crucial to grasping the scenario debate.

  • Integrated assessment modelling

    The article concludes with discussion of how individual integrated assessment models have outsized influence on climate projections. Understanding what these models are, how they combine economic, energy, and climate systems, and their limitations illuminates the methodological critiques raised in the article.

Sources

The battle for climate science and policy past—and why it matters

by Roger Pielke Jr. · The Honest Broker · Read full article

“Who controls the past controls the future: who controls the present controls the past” — George Orwell, 1984

Last week in Belém, Brazil the 30th Conference of Parties to the U.N Framework Convention on Climate Change (UNFCCC) concluded with little accomplished, according to most observers.

Perhaps the most significant accomplishment was formalizing a fully Orwellian characterization of the recent history of climate policy — See my post last week for why the UNFCCC characterization of moderating trends in climate projections is straight up misinformation.

Below is an excerpt from the COP30 agreement that turns flawed scenarios into policy success:

Acknowledges that significant collective progress towards the Paris Agreement temperature goal has been made, from an expected global temperature increase of more than 4 °C according to some projections prior to the adoption of the Agreement to an increase in the range of 2.3–2.5 °C and a bending of the emission curve based on the full implementation of the latest nationally determined contributions, while noting that this is not sufficient to achieve the temperature goal;

Today, I ask and answer — When should the climate community have first recognized that its projections of future climate change were based on flawed scenarios and taken action to correct course?

The answer, in short, is 2017.

That’s when Justin Ritchie and Hadi Dowlatabadi published their seminal paper:1

Ritchie, J., & Dowlatabadi, H. (2017). Why do climate change scenarios return to coal? Energy, 140:1276-1291.2

That paper altered the trajectory of my own work on climate. It found that the scenarios underpinning essentially all of projective climate research and the basis for the IPCC assessments were fundamentally flawed.3

They argued:

This paper finds climate change scenarios anticipate a transition toward coal because of systematic errors in fossil production outlooks based on total geologic assessments like the LBE model. Such blind spots have distorted uncertainty ranges for long-run primary energy since the 1970s and continue to influence the levels of future climate change selected for the SSP-RCP scenario framework. Accounting for this bias indicates RCP8.5 and other ‘business-as-usual scenarios’ consistent with high CO2 forcing from vast future coal combustion are exceptionally unlikely. Therefore, SSP5-RCP8.5 should not be a priority for future scientific research or a benchmark for policy studies.

Despite — or perhaps because of — its profound significance, Ritchie and Dowlatabadi 2017 was largely ignored by the climate science community. In the first three years ...