Do such people even exist?

The National Aeronautics and Space Administration (NASA) makes the following claim on its web site (1):

…97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are very likely due to human activities.

The assertion in itself is not very bold or even interesting as there is likely not a single “scientist” anywhere who would disagree with the basic claim notion that humans have altered atmosphere to some extent and/or effect. But what should be of interest is the concept of a “climate scientist.” Is the study of climate a “science” and are the people who engage in it “scientists”?

The fundamentalist view of what is a science is perhaps best expressed by 1908 Nobel Prize winner and “father” of nuclear physics, Ernest Rutherford, who said:

All science is either physics or stamp collecting.

One interpretation of this sentiment is that nature and its processes may only be completely understood through the study of how matter and forces operate on the most basic level. Absent this, all other study is merely an amassing and cataloging of various information and observations.

A more generous view of science is as a process or method of learning about how nature works on a larger, more directly observable scale. This definition expands “science” from the study of matter and forces to chemistry, biology and their many derivative fields. But the common theme running through all these different fields is the process of science or the scientific method.

The climate is complex and it goes without saying that a Rutherfordian understanding of it is impossible. Even a far more general understanding of how energy flows on a short-term basis in the climate system is beyond current comprehension.(2) So that leaves us with the possibility of studying climate via the scientific method.

As we think of it today, the scientific method consists of four basic steps:

Formulate an idea or hypothesis to be tested. Collect and analyze relevant data that will adequately test the hypothesis. Evaluate the results and refine the hypothesis. Repeat the process until the hypothesis can be accepted or discarded.

In terms of climate science, the scientific method then entails making predictions about the future climate and testing them to see how accurate they are.

As experiments with actual climate are pretty much impossible to conduct, when it comes to climate science, this process has been used to predict global temperature. A number of mathematical models of the climate have been constructed to predict future mean global temperature. That these models have so far pretty much failed to predict the mean global temperature trend is not a shortcoming of their general intent so much as it of their individual and collective failures to accomplish what they set out to do. In other words, it’s not that modeling can’t work; it just that the existing models don’t predict global temperature very well. Predictive climate modeling is a scientific process and we can consider those who engage in it to be climate scientists.

It is, of course, not enough to merely make predictions to be a scientist. A senior NASA climate scientist recently stated at a conference:(3)

What’s the use of having developed a science well enough to make predictions if, in the end, all we’re willing to do is to stand around and wait for them to come true?

The hubris of this statement is that allegedly scientific predictions about the climate don’t need to be tested, just asserted. This flies in the face of the scientific method. “Trust me” is not a scientific concept.

Also falling into the realm of non-science, at least on a practical level, are predictions that are non-testable or non-verifiable. Many predictions have been made about future climate. Some of these predictions are ongoing and can be regularly verified (i.e., climate models), but other predictions are about the climate 50 or 100-plus years in the future. As these predictions are not really practically verifiable, they trend toward non-scientific the further into the future they extend.

In stark contrast to the predictive nature of climate modeling is the study of past climate. The most famous of these efforts is the infamous “hockey stick” graph, which purported to describe the past 1,000 years of average global temperature. Regardless of how such study is undertaken, it is not and never will be scientific in nature for the simple reason that hypotheses about past climate can never be verified or confirmed. We can never measure what the mean global temperature was 1,000 years ago ⎯ there is great dispute over current temperatures ⎯ so confirmation and verification of historic claims is impossible. Such study may be interesting and may produce useful information, but it is not science. The people who engage in it are not scientists.

So what, then is a climate scientist? A climate scientist is someone who makes predictions about the climate, tests them and then repeats the process until he has developed a reliable explanation for how some aspect of the climate operates. Modelers who work with global temperatures may be considered as climate scientists ⎯ provided they also have other scientific characteristics, such being unbiased, honest, transparent, etc. Study of past climate does not constitute science nor does the making of untestable predictions.

Now that we know what a climate scientist is, how many of them are there and what do 97 percent of them agree on, if anything?

It would be very difficult to estimate the number of climate scientists there are in the world. But we can make a couple of broad generalizations. There are many more now than there were say 25 years ago simply because interest in and money for climate research is exploded during that period. As described by the American Institute of Physics:(4)

Until the middle of the 20th century, the discipline of climatology was a stagnant field preoccupied with regional statistics representing a static “normal” climate. The study of climate change (what to many climatologists seemed a contradiction in terms) was only an occasional interest of individuals who worked in divergent ways, and scarcely knew of one another’s existence. It had little to do with meteorology, which itself was predominantly a craft that paid scant attention to physical theory. The Second World War and Cold War promoted a rapid growth of meteorology, which some practitioners began to combine with physical science in hopes of understanding global climate dynamics. But the dozen or so scientific disciplines that had something to say about climate were largely isolated from one another. In the 1960s and ’70s, worries about climate change arose and began to push the diverse fields into contact. Scientists interested in climate change kept their identification with different disciplines but increasingly developed ways to communicate across the boundaries, for example in large international projects. Around the turn of the 21st century the Intergovernmental Panel on Climate Change institutionalized an unprecedented process of exchanges; its reports relied especially on computer modeling, which became a center of fully integrated interdisciplinary cooperation.

But asking how many climate scientists there are is really the wrong question to ask. As discussed above, if someone formulates a hypothesis about the climate, tests, evaluates and refines it, and then repeats the process with the intention of arriving at some understanding of how the climate works, then that person can be considered to be a climate scientist. This is where the rubber hits the road, though.

While there are many more people now than in the past who might imagine themselves as “climate scientist,” if you limit the “climate scientist” to someone who goes about the process described above for studying the climate, many fewer of them qualify. Many ersatz “climate scientists” study past changes in climate. Many make apocalyptic but untestable predictions of event decades and centuries into the future. But as discussed previously, while this work may be interesting, it’s not science and the people who do it are not scientists (at least because of such work).

This leads us to back NASA’s claim about the 97 percent so-called “consensus.” The “97 percent” claim largely arises from the claims and work of Al Gore, Naomi Oreskes and John Cook. The idea of a consensus of scientists concerning global warming was birthed with the 1995 release of the second report from the Intergovernmental Panel on Climate Change. As reported by the New York Times (Sept. 10, 1995):(5)

In an important shift of scientific judgment, experts advising the world’s governments on climate change are saying for the first time that human activity is a likely cause of the warming of the global atmosphere. While many climatologists have thought this to be the case, all but a few have held until now that the climate is so naturally variable that they could not be sure they were seeing a clear signal of the feared greenhouse effect — the heating of the atmosphere because of the carbon dioxide released by burning coal, oil and wood… But Dr. [Tom} Wigley and others involved in the reassessment say it is not yet known how much of the last century’s warming can be attributed to human activity and how much is part of the earth’s natural fluctuation that leads to ice ages at one extreme and warm periods at the other. Nevertheless, the panel’s conclusion marks a watershed in the views of climatologists, who with the notable exception of Dr. James E. Hansen of the NASA Goddard Institute for Space Studies in New York have until now refused to declare publicly that they can discern the signature of the greenhouse effect. The new consensus, as represented by the intergovernmental panel, seems likely to stimulate more public debate over how seriously the threat of climate change should be taken. [Emphasis added]

Despite the claim, there never was any such consensus among the contributors to the IPCC report. No vote was ever taken among the contributors and many contributors disagreed with the report’s conclusion, which was not drafted and agreed to by all the contributors. Instead, the report’s conclusion was written by a much smaller group of “inside” individuals who “summarized” the report and then misrepresented them as the agreed-upon conclusions of all contributors.

In 2004, Harvard science history professor Naomi Oreskes attempted to solidify the notion of a consensus with a quick-and-dirty analysis published in Science magazine: (6)

That hypothesis [of a global warming consensus] was tested by analyzing 928 abstracts, published in refereed scientific journals between 1993 and 2003, and listed in the ISI database with the keywords “climate change”.

The 928 papers were divided into six categories: explicit endorsement of the consensus position, evaluation of impacts, mitigation proposals, methods, paleoclimate analysis, and rejection of the consensus position. Of all the papers, 75% fell into the first three categories, either explicitly or implicitly accepting the consensus view; 25% dealt with methods or paleoclimate, taking no position on current anthropogenic climate change. Remarkably, none of the papers disagreed with the consensus position.

Oreskes’ claim of a 75% consensus on climate change was soon debunked as it was discovered that her search of the scientific literature was based on the term “global climate change,” not “climate change.” Had her search employed “climate change,” I would have produced more than 12,000 studies.(7)

The next major claim of a scientific consensus on climate occurred in 2010 when manmade climate change advocates published a paper in the Proceedings of the National Academy of Sciences claiming a 97-98% consensus of climate scientists based on publication and citation data from 1,372 “climate researchers” who had published at least 20 papers.(8) The study was a clumsy and arbitrary exercise in dividing scientists into “believers” and ‘non-believers.”(9)

The next effort to solidify in the public’s imagination a consensus on global warming was the May 2013 publication claiming a 97.1% consensus based on the abstracts of 11,944 papers on climate published between 1991 to 2011.(10) The paper reported:

We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW, 0.7% rejected AGW and 0.3% were uncertain about the cause of global warming. Among abstracts expressing a position on AGW, 97.1% endorsed the consensus position that humans are causing global warming.

A subsequent analysis of this claim reported that only 0.3% ⎯ not 97.1% ⎯ of the papers actually supported the notion that humans had caused most of the warming observed since 1950.(11)

Despite all the aforesaid claims and counterclaims, what has been disregarded in all these exercises-in-counting is how many of the surveyed individuals are “climate scientists” doing “climate science”? Certainly many researchers have published many articles on many aspects of climate. But how much of it is actually scientific in nature? How much of it is mere stamp collecting? No one has really answered that question.