A friend of mine is a journalist who writes about scientific issues for major national publications. He recently wrote a piece trying to explain why some people doubt an established consensus in the physical sciences. One consensus he cites is that emissions of warming gases pose a “serious threat.” Being conflated with critics of evolution and vaccines got under my skin, so I responded with the following email.
From: Caleb Rossiter
Subject: Hi from Caleb, the luke-warmist
Dear _________: I just read your piece in ______________ on doubters of a scientific consensus. You include with modern doubters of Darwin, Galileo, fluoride, and vaccines those of us who study the science, math models, and statistics of “climate change” and find little evidence of human-caused climate catastrophe. I think that our inclusion on that list is inappropriate at present.
Theories about evolution and vaccines, or claims about the damage done to human health by GMOs or by chemicals, can all be tested by controlling for intervening variables that also affect rates of damage. These hypotheses can then be confirmed or rejected to a degree of certainty. For example, Rachel Carson on DDT causing cancer, Mother Jones magazine on industrial chemicals reducing sperm counts, and Erin Brockovich on chromium-6 causing a litany of ailments were all proved wrong with proper statistical controls.
However, in Earth’s poorly understood and complex, interactive climate system, many intervening variables are impossible to control for accurately. As a result, predictions about climate changes are extremely hard to test. Climate claims at present are fundamentally speculative, rather than, as in the other examples of science cited in your article, definitive.
I am just a small fry among the big fish like Lindzen, Happer, Dyson, Soon, Pielke, pėre et fils, Curry, and Spencer who think this. But I have taught math models and statistics for a decade at American University, and I am proud of the work my students have done to assess the climate “consensus” you cite.
Yes, the United Nations summary you cite concludes that most of the half degree F warming from 1980 to 2000 (it has held flat for the 15 years since then) was the result of human emissions. But the justification for this conclusion comes almost entirely from the fact that a few modelers, using hundreds of parameters for unknown and currently unknowable interactions, can get a decent back-fit on previous global mean temperatures when they assume a certain sensitivity of temperature to CO2 and methane levels.
That is hardly the “scientific consensus” you claim. It’s a mathematical effect, which can also be produced with baseball batting averages as the correlated variable, given enough tuning of the other parameters. And the modelers have had to cut their sensitivity almost in half recently to account for the recent 15-year hiatus.
The modelers themselves call their future figures “scenarios” and not “predictions.” They also acknowledge that they must resort to solar and other natural variations to model an even greater temperature rise from 1890 to 1940, since industrial CO2 in that era would have had little effect. Their scenarios have huge error bands, in part because the laboratory effect of CO2 on temperature is a square root rather than a linear function, meaning that the impact of additional CO2 on temperature levels off, rather than keeps increasing. This is because the CO2 molecules, which happen to oscillate at the same frequencies as infrared leaving the atmosphere, get “filled” with the resulting heat-trapping interactions, and absorb less and less of the escaping infrared over time.
More importantly, the “climate change” that drives policy choices is not the modest temperature rise in the past 130 years, whatever its cause, but rather its effects. There is absolutely not a scientific consensus that human-caused climate change is “a serious threat.” The UN report provides little to show that droughts, hurricanes, and sea height have increased due to, or even with the warming. I know because for many years my students have taken the individual, usually peer-reviewed studies cited in the U.N.’s footnotes and analyzed them for their final projects, so I’ve had to read all the studies.
—All the best, Caleb
A luke-warmist catastrophe-denier and hopeful recipient of those energy company research funds you say are sloshing around out there for climate skeptics…tell ‘em I’m waiting!
P.S. I have written much on this topic. One piece in the WSJ about the need for carbon-based electricity for Africa got me fired from my anti-imperialist think-tank last year. In this polarized debate, newspapers that adopt the “consensus” had, of course, turned it down. It’s all on my blog, We Love Electricity, on calebrossiter.com.