Wood Romances

Expected Global Temperature Change from Solar Variability Alone, Assuming ECS = 3 C In a previous post , I considered whether there is a "continuing debate" over whether current climate changes are being caused in part by solar variability. This is effectively part 2 of that post. The evidence we currently have is clear that solar variability has been negligible since 1850, and particularly after 1960. There no significant ongoing debate on this point, as best as I can tell. However, the question remains, how much can the Sun affect climate? After all, the Sun may well have affected climate between 1850 and today, even if the combined effects were negligible over the last 170 years. To answer this question, we can think of the Sun's affect on climate on at least three different time scales: 1. Decadal : Given that solar variability operates on roughly 11-year cycles, TSI increases and decreases on roughly decadal time scales. But what they add to warming as TSI increases...

In 2020, Zeke Hausfather (and others) published a study in Geophsysical Research Letters[1] examining the performance of climate models in relation to observational data. Their conclusion was that "We find that climate models published over the past five decades were skillful in predicting subsequent GMST changes, with most models examined showing warming consistent with observations, particularly when mismatches between model-projected and observationally estimated forcings were taken into account." Given the selection criteria for selecting models described in Hausfather's paper, most of the models produced results that were statistically indistinguishable from observations. Reliability of Models in Hausfather et al 2020. However, just last month, Nicola Scafetta examined the performance of the individual CMIP6 models which contributed to projections in the AR6 report.[2] This paper was published in the same journal as Hausfather's paper a couple years ago. The CMIP...

Andy May recently wrote an opinion piece in the Washington Examiner[1] that I think warrants a rebuttal. If you haven't heard of him, Mr. May is a petroleum geologist who somewhat inflates his credentials when sharing his opinions to obscure his conflict of interest with climate science. He claims that he is a "petrophysicist" (he's a petroleum geologist with a BS in Geology), a "paleoclimate expert" (which he demonstrably isn't, see below), and a member of the CO2 Coalition (which he is). But he's popular in the contrarian blogosphere, so I think there are some things we can learn from interacting with his claims here that can yield some helpful insights into climate science and the scientific method. In this opinion piece, Andy May is claiming that Karl Popper's philosophy of science should cause us to see that climate change is unfalsifiable and therefore pseudoscience. Well, I think that's what he's trying to say but he kind of blunde...

This is part 1 of  review of the claims in Connolly et al 2021. You can see part 2 here . A paper was published in 2021 arguing that scientists have been premature to rule out the possibility that the Sun is the dominant explanation for the current warming trend. One key element in this argument is that there is continued disagreement over the degree of solar variability in reconstructions of Total Solar Irradiance (TSI) since 1610.  Some reconstructions show "low solar variability," and if those are correct, then current warming may be best explained by anthropogenic forcings. However, if "high solar variability" reconstructions are correct, then solar variability may explain most of current warming. So Connolly et al argue that "the answer to our question 'How much has the Sun influenced Northern Hemisphere temperature trends?' depends substantially on which estimate of TSI we choose."[1] But is this correct? Connolly et al Figure 2 Figure 2 in h...