Ian Clark is a Ph.D.-trained expert in paleoclimatology and Quaternary geology and was for many years a Professor of Environmental Geoscience at the University of Ottawa. In this chapter of the Canary in a Climate World Vol. 3 we’re discussing in this series, he says that when he began his career he was a true believer in the CO2-driven climate change story, so much so that he changed the name of a course so he could work in the topic. But something funny happened on the way to the consensus: he looked at the data. More precisely, he had a conversation with a senior and highly-esteemed colleague who had studied the very-long-term CO2-and-climate record and told him there was no connection. “That forced me to go back and critically examine the evidence,” Clark said. “And when I did, what I found was deeply concerning.” Not “concerning” as in climate-crisis-we’re-all-going-to-die, but concerning as in the data are at odds with what we keep being told. So the scientific establishment isn’t self-correcting in keeping with the true scientific method.

In his chapter Clark goes through some of the scientific issues that forced him to change his mind. For instance there have been long intervals in the Earth’s history in which CO2 and average temperatures moved completely independently of each other. Also, more recently, over the past million years CO2 and climate move together, but close examination of the data show CO2 responds to climate, not the other way around. And the big picture is that climate always changes on all time scales, meaning natural drivers are in charge and CO2 is not the Earth’s thermostat. And with regard to one current hot topic, in his discussion of extreme weather he points out that over the long term wildfire activity has not consistently been increasing, and there are other explanations for the anomalous 2023 outbreak of forest fires in Canada.

His contribution is not without its flaws, related to the fact that for all its virtues this book was not as rigorously edited as it should have been. (And he is one of the editors.) At one point Clark states that “IPCC Science reports all conclude that most of the observed 20th century warming is natural”, adding that the media never point this out. We’re pretty sure this claim is not correct. Certainly the latest AR6 says almost all the warming since 1850 is anthropogenic and natural causes contributed nothing. So if the IPCC has elsewhere attributed most warming from 1901 to 1999 to natural causes Clark should have provided a page reference or other verifiable source.

On the positive side, Clark discusses the key role of water vapour in the atmosphere and its connection to cloud cover, the decline in which, he points out, has caused much of the warming of the past 20 years and which cannot plausibly be described as caused by rising CO2. He also weighs in on why Net Zero remains infeasible. Nuclear is the only viable emission-free electricity source that might displace (some fossil) but is very expensive and build times are far too long, especially in Canada.

He concludes by pointing out that the foolish pursuit of Net Zero is not only economically harmful, it’s environmentally harmful as well because of the dirty mining for the inputs to wind and solar, the enormous “footprint” of the latter in particular, and the harm to birds from the former. But, he notes, “it suits the privileged western 1% who vote green and buy carbon credit indulgences for their vacations abroad.” Yes, and we will continue pointing it out ourselves, confident that however slowly, this madness too shall pass with crucial help from people like Clark.