If 97% of Scientists Say Global Warming is Real, 100% Say It Has Nearly Stopped

John Cook’s methodology proves that there is a “pause consensus”.

Guest essay by Paul C. “Chip” Knappenberger and Patrick J. Michaels, Center for the Study of Science, Cato Institute

The central premise of “global warming” is that human greenhouse-gas emissions will lead to a rise in the earth’s average surface temperature, and that as emissions continue to increase (a result of population growth and the desire to improve public health and welfare through increased energy availability), global average temperature will rise ever faster, that is, accelerate.

The U.N.’s Intergovernmental Panel on Climate Change (IPCC), back in 2007, claimed the acceleration was happening. This is a central part of both their global warming meme and the notion that it will lead to all sorts of negative consequences (and few, if any, positive ones).

Figure 1. Global average surface temperature history with trends through various periods emphasized by the IPCC to bolster their argument that global warming was accelerating (source: IPCC Fourth Assessment Report).

As proof the story told by the IPCC represented the “consensus of scientists,” a research team led by John Cook, founder of the website skepticalscience.com, (which is only “skeptical” about “skeptics”) surveyed the topical scientific literature, and categorized relevant publications as either endorsing the “scientific consensus” that “humans are causing global warming,” or rejecting it. They found that of those papers in which the authors expressed their opinions, 97.1% endorsed the “scientific consensus.”

The results of this study have been trumpeted ever since by climate alarmists and supporters of efforts to curtail greenhouse gas emissions the world over. President Obama even tweeted it:

While the White House doesn’t exactly have a reputation for being evenhanded about climate change, we still need to point out that the Cook et al. results said nothing about it being “dangerous.”

What Cook et al. did claim to find—that a high percentage of scientists that think that humans play some role in “global warming”—seems to comport pretty well with our own experiences with climate scientists and the climate literature. We definitely would fall within Cook’s 97 percent.

[Note: there is fair amount of criticism directed at the Cook et al. study, and the accuracy of the 97% number, and we are not specifically endorsing it here. Put simply, some think it’s the data that have been “Cooked” and we would not be surprised if some day the paper is retracted—but, regardless of the details, the percentage is still high].

The fact humans play a role in the enhancing the greenhouse effect leading to global warming is hardly actionable. The relevant questions are “How?” and “How much?”

The answers to these questions (and the specifics and details) are required to inform policy decisions. And, with regard to these, the science is most definitely not settled.

For example, is global warming really accelerating?

Not these days. In fact, observations show that the rise in the global average surface temperature has been little different (in the case of the University of East Anglia record, no different) from zero for the past 18 years or so. So instead of accelerating, global warming is actually decelerating, or, (nearly) stopped.

This period is colloquially known as the global warming “hiatus,” “pause,” or “slowdown,” and its existence seriously undermines the high-end, high-impact climate scenarios so beloved by the IPCC.

Is it the “consensus of scientists” that this “hiatus” is real, or is it just a manifestation of the “skeptical” global warming naysayers as we have so often been told?

So, we decided to use Cook’s own (debatable) methodology to find out.

We identified papers published between 2009 and 2014 and currently cataloged in the Web of Science database that included either the term “pause” or “hiatus” or “slowdown” and subsequently, the terms “global” and “temperature.” We then read the abstracts of those papers (or the papers themselves if further investigation was required) and assigned them to one of the following three categories: “not applicable,” “acknowledging the existence of a slowdown or stoppage in global warming (as reflected in the earth average surface temperature) in recent years,” and “arguing that a slowdown or stoppage of global warming (as reflected in the earth average surface temperature) has not occurred in recent years.”

Of the 100 papers we identified, 65 didn’t have anything to do with recent global temperature trends (these typified papers published prior to about 2010). Of the remaining 35 papers, every single one of them acknowledged in some way that a hiatus, pause, or slowdown in global warming was occurring.

In other words, we didn’t find a single paper on the topic that argued the rate of global warming has not slowed (or even stopped) in recent years. This is in direct opposition to the IPCC’s contention that global warming is accelerating, and supports arguments that the amount of warming that will occur over the remainder of the 21^st century as a result of human fossil fuel usage will be at the low end of the IPCC projections, or even lower. Low-end warming yields low-end impacts.

We surely may have missed a few papers that were not cataloged in the database we used, or that weren’t captured by our search terms, but the evidence is overwhelming—virtually all (if not actually all) scientific papers that mention a hiatus or pause agree that it exists.

So while 97% of scientists may agree that global warming is caused by humans, virtually 100% agree that global warming has stopped or slowed considerably during the 21^st century.

Tweet that, Mr. President!