This is the second of seven parts; read the first part on our website: www.mllg.us.
The most frequent, and likely strongest, argument by believers in manmade warming is the existence of a near-unanimous (97%) consensus of climate scientists. It is therefore critical to deconstruct this assertion, including its origin, accuracy and scope.
The original and most referenced source is a 2013 study by John Cook, who runs a website promoting catastrophic climate change. Cook wrote that 97.1% of the papers he surveyed agreed the earth is warming and human emissions of greenhouse gasses are the main cause. Cook took data, much from non-scientists, from the internet using the search phrase “sea ice climate change“. Cook counted papers stating there was manmade warming but not how much and included papers he believed implied it. Only 2% of the papers explicitly stated humans were the main cause of warming.
Cook’s work was reviewed by four professors who read the same papers; their findings, published in Science and Education magazine, concluded only 41 of all 11,994 papers (0.3%) endorsed the claim that human activity causes most warming. Many scientists Cook included protested and asked their papers not be counted.
The National Academy of Sciences published a survey by Stanford University student William Anderegg, who used Google Scholar to survey the 200 most prolific authors on climate change. He determined 97% to 98% believed man was responsible for most warming. His survey included only 200 out of many thousands published.
NASA’s website cites Cook and Anderegg for its 97% scientific consensus claim, thus lending its imprimatur. The media then glom on repeating the claim as coming from NASA. After that meme is repeated year after year by government, politicians, media and educators, many people (especially youth) unquestioningly adopt it as their mantra. Nonetheless, those who cite NASA really are relying on Cook and Anderegg. Note: NASA has also stated that changes in the solar orbit of earth, along with alteration to its obliquity (axial tilt), are responsible for changes in climate.
There are a few other sources alleging scientific consensus. A two-question online survey published in Eos claimed 97% of climate scientists agree temperatures have risen and humans are a significant contributing factor. Only 79 of 3,146 respondents claimed to be climate scientists. Last, in Science Magazine Naomi Oreskes alleged 75% of abstracts in scientific journals supported the view that human activity is responsible for most warming. However, many dissenting articles were excluded and the methodology was flawed. When subsequent researchers (Peiser, Schulte, et. al.) attempted to replicate the study, they found only 33% and not 75%.
Readers can judge the veracity of the 97% scientific consensus, which alleges only that the planet is warming and man is the main cause. That the earth is warming is uncontested and hence meaningless. Man as the main cause means only at least 51%. Thus, the putative consensus, which includes only a tiny number of climate scientists, extends only to humans causing at least 51% of warming – no other consensus.
It is imperative to understand what is not included in any claimed consensus: there is no scientific consensus about whether or not: (1) benefits from warming outweigh the harm; (2) warming is an existential, or even dangerous, problem; (3) we should attempt mitigation; (4) more CO2 is harmful; (5) CO2 significantly affects climate; (6) combatting warming is a high priority; (7) mitigation is preferable to adaptation; and (8) we should spend trillions today for uncertain and infinitesimal benefits in the distant future. None of these things are part of any claimed consensus.
Many Scientists Reach a Different Consensus
The Environmental Science & Policy Journal published a study reporting most climate scientists question climate data and computer models and believe climate science can’t predict future climate change. An American Meteorological Society survey reported that only 39% believe manmade global warming is dangerous.
In a particularly damning riposte, 31,487 physicists, 9,029 with PH.Ds, signed a petition stating: “We urge the US to reject the Kyoto Protocol. The proposed limits on greenhouse gasses would harm the environment and damage the health and welfare of mankind. There is no convincing scientific evidence human release of CO2 is causing, or will, in the foreseeable future cause catastrophic heating of the Earth’s atmosphere. Moreover, there is substantial scientific evidence that increases in atmospheric CO2 produce many beneficial effects upon the plant and animal environments of Earth.”
The 2018 Nobel Prize in Economics was awarded to William Nordhaus for his work on the economics of climate change. His work demonstrated economic policies necessary to limit warming do far greater harm to humans in reduced economic output and that it is better for governments to do absolutely nothing about climate change.
Finally, progressive arguments for scientific consensus ring hollow. Progressives embrace science when it suits their purpose but cynically deny science when it doesn’t as in, inter alia, nuclear energy, rent control, and minimum wage, all of which enjoy a genuine scientific consensus well above 90% opposed to their policies.
Next on October 27th is Part III – other arguments for manmade warming.