Wood Romances

A prepublication version of the Indicators of Global Climate Change 2025 (IGCC25) has recently been released. This report provides an annual update to IPCC's AR6 WG1 report concerning human emissions and global warming. The data provided as excel spreadsheets related to this report was extensive, and this allows me to produce some graphs I haven't been able to do before. These data do a really good job of showing the relative impact of human and anthropogenic forcings since 1750.  Using HadCRUT5 (1850-1900 Baseline) First I decided to show these forcings with GMST anomalies from HadCRUT5 to see how well the quantifications of forcings agree with observations for warming. This means for this section I'm limiting myself to values from 1850 to present. The graph below shows an update to Gillett's analysis used in AR6 that made it possible to conclude that human activity is responsible for virtually all the warming above the 1850-1900 mean. For this graph, I set HadCRUT5 to...

A couple months ago, I saw that the " Indicators of Global Climate Change 2024 " ( IGCC24 ) was published, which is an annual update on the state of global climate and how it is changing in response to human and natural forcings. The data provides the most up to date information on human emissions and associated changes in radiative forcings as well as an evaluation of the change in temperature. A graphical summary of this is below. From IGCC24 I thought it would be helpful to show how updated values for warming, EEI, and radiative forcings would impact calculations for Equilibrium Climate Sensitivity (ECS). Here's their accounting of the various natural and anthropogenic forcings. Note that s olar forcing in the diagram above is only for 2024 only and so disagrees with the accounting in the table below. Change in Radiative Forcing Forcer 1750-2024 CO2 2.33 ± 0.28 W/m² CH4 0.57 ± 0.11 W/m² N2O 0.23 ± 0.03 W/m² Halogenated GHGs 0.41 ± 0.08 W/m² Ozone 0.5 ± 0.25 W/m² Strat...

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 ...

Cenozoic CO2 and Temperature A new paper was published this month that I think will produce some exciting new insights for those interested in historical geology and paleoclimate studies. The paper is a product of the Cenozoic Carbon dioxide Proxy Integration Project (CenCO2PIP) Consortium, and it looks to reconstruct the proxy evidence for CO2 levels during the Cenozoic (the last 66 million years). The Cenozoic began after the asteroid impact (and/or volcanism) at the Cretaceous-Tertiary (K-T) boundary that caused the mass-extinction that included the extinction of non-avian dinosaurs. The value of this kind of work will have significant benefits for scientists as they seek to constrain estimates for long-term climate sensitivity (ESS). We can think of "sensitivity" on roughly three time scales:  TCR : On a near-immediate time scale, GMST increases with increasing CO2 in what is called transient climatic response (TCR), which generally speaking tells you how quickly temperat...