Wood Romances

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, 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...

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...

Accounting for Climate Forcings Puts ECS Near 3 °C From ClimateBrink The so-called "Climate Working Group," hired by the Department of Energy to write what Roger Pielke Jr termed a "red team" response to climate science  (my initial response is here ) is predictably critical of the central scientific estimate for ECS. The first ECS estimate I know of was calculated by Arrhenius, who concluded that 2xCO2 would cause between 4-6°C warming. This value was revised downward by Gilbert Plass in the 1950s to ~3°C, and since the 1970s this has become the standard estimate. The IPCC currently says the likely range is 2.5-4.0°C, largely as a result of Sherwood et al 2020 (S22),[1] which is still to date the most comprehensive assessment of ECS (Sherwood's likely range was 2.6-3.9°C). There is a growing body of scientific literature arguing that recent observational evidence is more consistent with an ECS closer to 4°C, suggesting that the IPCC may be a bit conservative on...