On June 17, we and our co-authors received a response to our letter to MIT President, Professor Reif, raising concerns about his letter to the MIT community in support of the Paris Climate Accord. Professor Reif’s response stated that he was confident in his position on the issue because it is consistent with the beliefs of experts that implementation of the Paris Accord is necessary to save the world from harmful effects of man-made global warming. We are not reassured.
Not only have leading experts expressed directly opposing beliefs—including MIT’s own Professor Lindzen, and Princeton’s Professor Dyson—Professor Reif’s argument by authority runs counter to conclusions from decades of research on the value of expert opinions about what will happen in the future. They are no more accurate than those of non-experts and—for complex situations particularly—neither is much better than guessing.
The first review of the literature on expert opinion forecasts was published in MIT’s Technology Review under the title “The Seer-Sucker Theory: The Value of Experts in Forecasting” (Armstrong 1980). Many other studies have supported that review’s conclusion that expertise on a subject does not confer superior ability to see into the future. Tetlock’s (2005) landmark book, Expert Political Judgment, is notable.
The physical sciences are not immune. Not even when leading experts make predictions about the implications of their own work. For example, when Ernest Rutherford split the atom in 1933 he predicted that the energy released was too small to ever be of practical use. Albert Einstein concurred a year later, predicting that man would never be able to harness nuclear energy from shattering atoms.
Efforts in recent years to create alarm by promoting the hypothesis of dangerous man-made global warming as a scientific fact—and to thereby influence public policy—is not a new phenomenon. Scientists acting as advocates—in concert with lobbyists and politicians—have been responsible for at least 26 analogous environmentalist alarms in the past; most of them over the last 100 years.
Green and Armstrong (2011) found that all of the alarms were the product of an unscientific forecasting method: experts’ unaided judgment. All 26 turned out to be false alarms, which suggests a strong bias towards alarm. Governments took action in response to 23 of the alarms to no apparent benefit. Indeed, the policies and regulations implemented by governments were clearly harmful in the case of most (20) of the alarms.
Given the history of environmentalist alarms, it would be a surprise if the dangerous manmade global warming alarm were an exception. It isn’t, as Green and Armstrong (2007) showed. The IPCC’s temperature projections were the outcome of procedures that violated 81% of the scientific forecasting principles that the IPCC report provided sufficient information to rate.
Surprisingly, given the extraordinary level of research grant funding that has been thrown at the topic of climate change, we are aware of only one attempt to apply scientific (evidence-based) forecasting to long-term global temperatures. That effort at scientific forecasting resulted in the Green, Armstrong, and Soon (2009) no-change forecast. As the name implies, the no-change forecast gives no cause for alarm.
Our Green-Armstrong-Soon forecast of no-change in global average temperatures over the 21st Century is consistent with the state of knowledge on climate as described in the last paragraph of Section 14.2.2.2 in Chapter 14 of the IPCC Third Assessment Report. The report states: “In climate research and modeling, we should recognize that we are dealing with a coupled non-linear chaotic system, and therefore that the long-term prediction of future climate states is not possible.” In other words, the IPCC report authors believe that forecasting long-term trends in climate is impossible.
Readers might be excused for not being familiar with that statement of profound uncertainty about the climate. It was not included in the Summary Report for Policymakers given to the media and to political leaders.
The Green, Armstrong and Soon (2009) no-change forecast has been shown to be substantially more accurate than the IPCC dangerous manmade global warming projections (Green and Armstrong 2014). The longer the forecast horizon, the less accurate are the IPCC projections. For example, the IPCC projection errors were 12 times larger than those of the no-change forecast for horizons from 91 to 100 years ahead.
The IPCC’s climate modelers recently conceded that their projections of CO2-caused global warming have been at odds with measured temperatures over the 21st Century, which have shown no trend while atmospheric CO2 levels have continued to increase unabated. As the modelers quaintly put it: “Over most of the early twenty-first century… model tropospheric warming is substantially larger than observed” (Santer et al 2017). These facts should be sufficient to reject a hypothesis that has claims to being scientific.
The extraordinary 100% false alarm rate of environmental alarms raised by scientists (Green and Armstrong 2011) is not evidence of a failure of science, but of a failure of scientists to follow the scientific method. Scientists are subject to incentives and pressures that lead them away from following the scientific method, and to instead become advocates posing as scientists.
Most damagingly to science, scientists are rewarded for obtaining large research grants—especially from government. Governments do not fund blindly, they and their agents have political agendas. Rather than scientists as the experts in their fields deciding how they can best contribute to advancing knowledge, politicians, and bureaucrats determine what to research and how. Moreover, researchers are expected to deliver findings that are consistent with political objectives.
Warnings about the harm caused by governments becoming involved in science—such as President Eisenhower delivered in his Farewell Address in 1961—have been made for decades. In Armstrong and Green (2017), we provide solutions to the deterioration in the practice of science. Our solution is in the form of a checklist of Guidelines for Science that is based on the definition of science developed by Bacon, Newton, Franklin, and other pioneers of the scientific method.
We suggest that the practice of science could be saved from its deterioration into advocacy if universities used the checklist for choosing potential new hires and for rewarding current faculty on the basis of their contributions to useful knowledge. We hope that university presidents will show leadership by taking this important step in asserting independence for their scientists and reforming scientific practice.
Kesten C. Green is a senior research fellow at the Ehrenberg-Bass Institute at the University of South Australia Business School and a policy advisor to The Heartland Institute.
Willie Soon is an astrophysicist and a geoscientist based in Cambridge, Massachusetts.
J. Scott Armstrong, professor at the Wharton School, University of Pennsylvania, is a founder of the Journal of Forecasting, International Journal of Forecasting, and International Symposium on Forecasting. He is the creator of forecastingprinciples.
