Wood Romances

In a recent talk  (relevant excerpt  here ) given to an Australian political group called the Institute for Public Affairs (IPA), William Happer argued that doubling CO2 causes only 0.71 K warming, and that amount of warming for 2xCO2 is too small to matter. He then suggests that in order to make CO2 a problem, scientists had to invent giant feedbacks to amplify warming by as much as 10x the amount caused by CO2 alone. I've seen this claim repeated by others on X and other social media platforms, but as best I can tell Happer originates this particular argument. So I'd like to consider, is this plausible at all? I think it's pretty easy to investigate this and show conclusively that it is not. In fact, even Happer disagreed with this claim as recently as 2020. Happer's Argument At about the 1 minute mark of the above linked excerpt, Happer explains his math on how he arrives at 0.71 K for equilibrium climate sensitivity (ECS). He begins with the equation: F = εσT^4, whe

In January, I blogged about a lecture I watched from Jessica Tierney, a geologist who has done some fascinating work in paleoclimate, in which she described the research behind a new paper that was at the time still undergoing peer review. You can watch the video and see my previous thoughts about this here . Ever since I watched this lecture, I have been anticipating the publication of the paper and hoping that the text wouldn't be behind a pay wall so I could learn more about what Tierney shared in her lecture. Well, late last week, both of my hopes became a reality. The paper is published and the full version is available. The lead author is Emily Judd[1], and this appears to be a remarkable paper. The tl;dr for this paper is that Emily Judd and her colleagues put together a data analysis (PhanDA) reconstruction of global temperatures and CO2 for the last 485 million years (most of the Phanerozoic), and they found that GMST varied greatly on geologic time scales, ranging from

A recent paper[1] published in the MDPI journal Climate by Frank Stefani provides a wonderful illustration of why we should never treat papers from MDPI journals as having any competent, let alone robust peer review. This paper argues that TCR = 1.1°C (0.6°C - 1.6°C) for doubling CO2. I'm not going to evaluate the entire paper here, since that would take too much time. The paper does make some counterfactual claims, like there's a "nearly perfect correlation of solar activity with temperatures over about 150 years." That's objectively false, but the correlation between CO2 forcings and GMST has an r^2 = 0.88. There's also some comical contrarian alarmism in this paper: "we fear that the huge Milankovitch drivers will—perhaps much too soon—massively interfere with the solar and anthropogenic factors that were considered in this paper." There's a lot we could say about this paper, but I want to focus here on some elementary math errors that would

There's a conspiracy theory floating around the blogosphere and social media that argues (oddly) that climate scientists manufactured global warming by artificially lowering global temperatures. The "thinking" goes like this. Back in 1896, Svante Arrhenius calculated global mean surface temperature (GMST) to be 15°C. Following this, other scientists confirmed this value for later years. For instance, Hansen is reported to have claimed that value in 1981. The first IPCC report is claimed to confirm it again in 1990. In some incarnations of this conspiracy theory use other sources using 15°C, but the concept is the same. Then, after the so-called "pause" began in 1998, scientists needed another way to manufacture global warming, so they lowered GMST to 14°C so that they could increase it again. If that sounds confusing to you, it should. It doesn't make any sense. But let's unpack what's actually going on. Arrhenius' Calculation in 1896 Svante Arr

CO2 Coalition 's " Fact #8 " and " Fact #9 " want us to believe that more CO2 means more plant growth (Fact 8) and allow crops to feed more people globally (Fact 9). The claims here are not really new compared to other claims in this list of "facts," and we've already seen why these claims are misleading at best. We've seen in two posts ( here and here ) that increasing CO2 doesn't just cause greening through CO2 fertilization but also warming through the greenhouse effect. The latter increases heat stress for plants and limit their ability to make use of additional CO2 for photosynthesis. We've also seen here that CO2 Coalition just assumes that increases in corn yields are due to increased CO2 when the sources they cite actually attribute increases in crop yields to better hybrid corn and better technology. The logic of these facts is very similar. In "fact 9," we're shown a graph of grain production with CO2 and tempe

  CO2 Coalition 's " Fact #29 ," " Fact #30 " and " Fact #31 " are essentially the same strawman attacks having to do with claims about droughts that nobody is actually saying. They basically observe here that there has been no change in droughts in the US, and droughts are declining globally. Here are the graphs they use to support this point. And yet who said otherwise? It's well-documented that warmer air holds more water, with water vapor increasing by ~7% for every 1 C warming. So on average, we should expect to see decreases in droughts as a global average. CO2 Coalition is attacking as strawman here. Climate scientists also observe that in more arid areas with less water availability, warming increases vapor pressure deficit (VPD) which should drive local and regional increases in the frequency and intensity of droughts (I cover more about this here ). This is observed in the American Southwest and in other areas around the world. In wetter