Wood Romances

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...

One of the most common studies cited in favor of a low equilibrium climate sensitivity (ECS) was published by Lewis and Curry in 2018 (LC18).[1] Their paper used the standard energy balance equation I've used in previous blogposts to estimate both ECS and TCR. They arrived at median estimates with 95% uncertainties of 1.66 C for ECS (1.15–2.7 C) and 1.33 C for TCR (1.0–1.9 C). These values are significantly below the range estimated by the more recent IPCC assessment reports. Since the publication of this paper, Sherwood et al 2020[2], published what may be the most comprehensive assessment of ECS and found a 95% range of 2.3–4.7 C. Argument of LC18 So I thought it might be interesting to do a back-of-the-envelope style update to LC18. I think there are several reasons why this can be valuable. Since the publication of this paper, a number of new insights have been published: The publication of HadCRUT5 had significant improvements over HadCRUT4, even the dataset with kriging to li...