Posts

Is there a Pause in the Decline of Arctic Sea Ice Extent?

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A couple papers were published this year about the recent "pause" in the decrease in September sea ice extent (SIE). One paper, Stern 2025[1] shows that the trend in Sept. SIE has been indistinguishable from 0 since about 2007.  From Stern 2025 Likewise, England et al 2025[2] has found that 20-year trends have increased to the point where there is no longer a statistically significant downward trend for 2005-2024. England et al 2025 The publication of these two studies, plus coverage of at least the latter in the Guardian , has caused quite a stir among contrarians on social media, who are claiming this is evidence that AGW isn't really a problem after all, and perhaps natural variability is what's driving recent changes in sea ice extent and temperature. However, that's not the way the authors of these studies are saying. Instead, the authors see the long-term downward trend in sea ice as being very real and caused by human activity, but they are also saying that...

Pielke Jr and the Misrepresentation of AR6

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from IPCC AR6 WG1 Chapter 11 With all the misrepresentation of the scientific literature found in the recent DOE report, I thought it might be helpful to show that misrepresenting the scientific literature has a long tradition in contrarian circles, even among those who give the appearance of supporting the overall science presented in the IPCC technical reports. The strategy can serve an important rhetorical goal if you want to show that the science is on your side while taking a counterfactual stance on the science. If your goal is to show that position X (found in the media or in some scientific study) is wrong or not sufficiently supported by evidence, you can cite a series of papers with extremely selective quotations to give the false impression that this series of papers either falsifies Position X or undermines its credibility. This strategy appears to be a go-to strategy in the DOE report.  An interesting twist on this strategy is frequently used by those who want to say t...

The DOE Report on Urban Heat Islands

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I've written a lot on the effect of urbanization and urban heat islands  (UHI) on GMST and CONUS  trends, and I don't want to duplicate those efforts here, but I think this section of the DOE report deserves its own post. The DOE report (authored by the Climate Working Group) has a section on "Urbanization influence on temperature trends" on pp. 20-21 (section 3.3) that engages in a bit of rhetorical slight of hand that I find dishonest. In particular, their treatment of UHI involves two studies authored or co-authored by members of the Climate Working Group (CWG), but the report misrepresented one and casually dismissed the other. The report misrepresented a study by Roy Spencer and casually dismissed a paper co-authored by Judith Curry, despite the fact that this study provided conclusive evidence against the position taken in the DOE report. I consider this particularly dishonest. Their treatment of UHI begins with: Historical temperature data over land has been ...

The DOE Report on Plant Life During Low CO2

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One of the frequently repeated tropes in climate contrarian circles is the supposed " line of death " at 150 ppm below which, we're told, all photosynthesis stops, so all plant life dies and there's a mass extinction of life on Earth. CO2 Coalition loves to trot out this trope to claim that, since CO2 became as low as 170 ppm during the glacial cycles of the Quaternary, we were dangerously close to a mass extinction. They claim we're still "CO2 starved." They also tell us that Berner's 2001 CO2 models shows "an alarming downward trend toward CO2 starvation."  We're then apparently supposed to be thankful for fossil fuel emissions that have saved us from perhaps the extinction of all life on earth. The DOE report, authored by the "climate working group" (CWG), tones down this rhetoric a bit, but it's essentially the same claim with slightly different numbers: "At the end of the last glaciation CO2 levels had fallen to...

The DOE Report on Ocean Acidification

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The  DOE report, authored by the Climate Working Group (CWG) only has a little to say about ocean acidification, but what it does say is somewhat bizarre, biased, and extremely problematic; it reveals what I consider irresponsible and short-sighted thinking on the part of  CWG. Here's perhaps the most significant paragraph on p. 7. While this process is often called “ocean acidification”, that is a misnomer because the oceans are not expected to become acidic; “ocean neutralization” would be more accurate. Even if the water were to turn acidic, it is believed that life in the oceans evolved when the oceans were mildly acidic with pH 6.5 to 7.0 (Krissansen-Totton et al., 2018). On the time scale of thousands of years, boron isotope proxy measurements show that ocean pH was around 7.4 or 7.5 during the last glaciation (up to about 20,000 years ago) increasing to present-day values as the world warmed during deglaciation (Rae et al., 2018).Thus, ocean biota appear to be resilient...

The DOE Report: A Case Study in Scientific Misrepresentation

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WNA Heat Dome from Bercos-Hickey et al 2022 In preparing my previous post on my initial response to the DOE report, I stumbled on the report's assessment of Western North America heat dome in June 2021, and I discovered several ways in which the authors misrepresented the scientific research they used to support their position. It turns out in many ways I was just scratching the surface of the problems with their analysis of this event. Their assessment comes from pp. 96 and 97 of the DOE report, and it is structured as a rebuttal to a "rapid attribution analysis" that was published in Philip et al 2022.[1] This is their summary of that analysis: The WWA team generated international headlines with their analysis, which provided the following attribution statements (WWA, 2021; Philip et al., 2022): Based on observations and modeling, the occurrence of this heatwave was virtually impossible without human-caused climate change. The event is estimated to be about a one in 10...