Bad science is the foundation of fears of dangerous, manmade global warming and therefore of any policy recommended to reduce it.
If you’re like many Americans, you find that position surprising, because you’ve heard that many national academies of science, the United Nations Intergovernmental Panel on Climate Change (IPCC), and an alleged overwhelming consensus of the world’s scientists say the opposite.
So why should you judge that the skeptics are right and all those others are wrong?
Because the key to science is not counting to see how many people agree with you but testing hypotheses and theories against real-world observation.
By that criterion, the hypothesis of dangerous, manmade global warming fails. Miserably.
In a nutshell, from 1990 onward the IPCC and those who agree with it have said that human emissions of carbon dioxide should be warming the atmosphere at a rate of about 3˚ C per century, or 0.3˚ per decade. Until 2013, they said the rate could be as low as 2.0˚ per century (0.15˚ per decade) or as high as 4.5˚ per century (0.45˚ per decade), and in 2013 they adjusted the low-end estimate to 1.5˚, but 3˚ remains their best estimate.
They also claim that warming of more than 2˚ compared with pre-industrial times—and so far there’s been about 0.8˚ of warming since then—would be dangerous to human and other life. (That claim lacks persuasive empirical evidence, but we can accept it provisionally for the moment.)
How do their predictions compare with real-world observations?
Over the 36.5 years covered by our most reliable global temperature measurements—obtained by satellites—global average temperature (GAT) has risen, as illustrated in this graph, only 0.407˚. Continued for a century, that would be 1.115˚, or a decadal rate of 0.11˚, which is 27% lower than the lower-bound rate the IPCC claims, and 67% lower than IPCC’s “best estimate.”
To achieve the 3˚ “best estimate” for a century, GAT would have to rise another 2.593˚ in the remaining 63.5 years, a rate of 0.41˚ per decade, which is 3.7 times as fast as the observed rate so far. To achieve the 2˚ lower bound claimed for over 20 years, GAT would have to rise two-and-a-quarter times as fast as the observed rate. Even to reach the 1.5˚ the IPCC now claims is the lower bound, GAT would have to rise one-and-a-half times as fast as the observed rate.
And there is no empirically driven reason to think warming will accelerate in coming decades. On the contrary, because the warming effect of rising carbon dioxide concentration is logarithmic, warming attributable to it should slow, not accelerate, as CO2 continues its steady rise.
In short, there is no solid scientific ground to fear anthropogenic global warming.
That’s a good reason to sign An Open Letter on Climate Change to the People, their Local Representatives, the State Legislatures and Governors, the Congress, and the President of the United States of America.
Learn more by watching this video.
Frank Hilder says
Your comment that ” there is no solid scientific ground to fear anthropogenic global warming” is complete rubbish. You are cherry-picking data and are intentionally trying to mislead readers. Virtually every US and international scientific academy recognizes that increasing GHGs is and will have serious implications on the planetary climate system. Show us your sources of evidence.
E. Calvin Beisner says
After reading your accusation that I’m “cherry picking data” I expected to see some data in response. Instead I found an appeal to authority—which of course is unscientific. Not only that, but your appeal to authority misrepresents what the authorities affirm, which is not AGW of such rapidity and magnitude as to justify spending trillions of dollars to mitigate it that could otherwise be spent to solve other problems, but simply the claim that human activity probably caused most of the warming since about 1950 (i.e., >50% of roughly 0.4C)—a claim that, even if true, wouldn’t be particularly alarming, but that in fact is quite likely not true, as I’ll show in a moment.
First, have I cherry-picked data? No. I’ve taken the entire period of satellite data record. There are no satellite data earlier than that. And the satellite data are the most comprehensive and reliable we have, because they’re not contaminated by the quite significant differences in equipment, siting, and maintenance that contaminate the land-surface and ocean-surface data.
Second, is the claim, embraced by the IPCC, that human activity caused most of the warming over about the last 50 years true? Not likely, when we subject the temperature data to valid statistical analysis. That’s done in Ross McKitrick’s “HAC-Robust Measurement of the Duration of a Trendless Subsample in a Global Climate Time Series” (http://dx.doi.org/10.4236/ojs.2014.47050), which, after adjusting for heteroskedasticity (heteroskedacity) and autocorrelation (https://en.wikipedia.org/wiki/Autocorrelation), finds that in the weather balloon temperature data from 1960 through 2012 there is no statistically significant upward trend from 1960 to late 1977, a rapid stepwise upward shift in late 1977 (probably caused by the cyclical reversal of the Pacific Decadal Oscillation from negative to positive), and then no significant upward trend from 1977 through 2012, implying that atmospheric CO2, which rose steadily throughout the half-century period, had no significant impact on global average temperature during that time. It also found “a trendless interval of 19
years duration at the end of the HadCRUT4 surface temperature series, and of 16 – 26 years in the lower troposphere”—and since there has been no significant warming trend since 2012 (the end of McKitrick’s data for his 2014 article), that means the trendless intervals now run about 22 years by the HadCRUT4 surface temperature series and 19 – 29 years for the lower troposphere. One might have wished that the climate scientists themselves had applied such proper, valid statistical methodology to the analysis of their data, but few if any of them are professional statisticians, and therefore few if any were even aware of the problems of heteroskedasticity and autocorrelation, much less able to apply the proper statistical techniques to control for them. (This isn’t the only instance in which a professional statistician has pointed out the invalid statistical methodology of AGW alarmists. See “Ad Hoc Committee Report on the ‘Hockey Stick’ Global Climate Reconstruction” (the “Wegman Report,” http://www.uoguelph.ca/~rmckitri/research/WegmanReport.pdf).
E. Calvin Beisner says
By the way, the length of the period during which there’s been no statistically significant global warming according to the satellite data has now reached 18 years and 9 months. See the article and graph at http://www.climatedepot.com/2015/11/04/no-global-warming-at-all-for-18-years-9-months-a-new-record-the-pause-lengthens-again-just-in-time-for-un-summit-in-paris/.