Unsettled Climate Science: 30 Years Apace

By Robert L. Bradley, Jr.

Climate activist Emily Akin has called it “the most important climate story of the last 10 years: The quiet, concerted effort by fossil fuel interests to conceal and deny climate science, for the purposes of preventing climate action.” The bad guys had been at it for “the last three decades,” she contends, creating an illusion of unsettled science that “allowed the public to take their minds off the problem.”

In the oil and gas capital of the world, the business editorialist of the Houston Chronicle, Chris Tomlinson concluded: “Exxon scientists … have accepted climate change as fact since at least the mid-1980s.”

True, some tasked Exxon employees opined about the potential of carbon dioxide (CO2) to warm the planet with negative effects. But other employees rejected a dire result, as did the company as a whole. And, in fact, external experts, in and out of the scientific community, did not know the answers either. And in some fundamental ways, they still do not.

Global Cooling?

A much smaller climate-science community 45 years ago was conflicted over the human influence on global climate from industrial emissions. Important scientists tilted toward global cooling and the threat of a new Ice Age from sulfur dioxide (SO2) emissions from coal plants in particular.

Future Obama science advisor John Holdren, for one, noted that aerosol pollution was blocking sunlight with the potential to “start another ice age.”

Scientists also debated how humans were artificially influencing the climate in offsetting ways. “[T]here can be scant consolation in the idea that a man-made warming trend might cancel out a natural cooling trend,” declared Paul Ehrlich and Holdren in 1977. “Since the different factors producing the two trends do so by influencing different parts of Earth’s complicated climatic machinery, it is most unlikely that the associated effects on circulation patterns would cancel each other.”

“Predictions of future climate trends by Stephen Schneider and other leading climatologists, based on the prevailing knowledge of the atmosphere in the early 1970s,” Paul and Anne Ehrlich would later admit, “gave more weight to the potential problem of global cooling than it now appears to merit.”

Cooling, warming, or both—it was industrial-related and thus bad. Welcome to the deep-ecology bias against “human centeredness” at the expense of pristine nature. This is Al Gore’s “dysfunctional civilization” where fossil fuels (aka dense, mineral energies) have disconnected us from “the vividness, vibrancy, and aliveness of the rest of the natural world.”

Global Warming Controversy

The scientific consensus would shift to global warming with carbon dioxide (CO2) outdistancing the cooling influence of SO2. But James Hansen’s dramatic testimony in the summer of 1988, the beginning of the consensus, was quite controversial among his peers.

Hansen vs. the World on the Greenhouse Threat,” read a headline in Science magazine by climate scribe Dr. Richard Kerr. Dissent ran high. Wrote Kerr: “What really bothers [fellow scientists] is not that they believe Hansen is demonstrably wrong, but that he fails to hedge his conclusions with the appropriate qualifiers that reflect the imprecise science of climate modeling.”

“The [natural] variability of climate from decade to decade is monstrous,” stated one leading scientist. “To say that we’ve seen the greenhouse signal is ridiculous.” Said another to Kerr: “Confidence in detection [of anthropogenic warming] is now down near zero.”

This uncertainty and debate led one cooling-to-warming climatologist to go political. Stated Stephen Schneider in 1989:

On the one hand, as scientists we are ethically bound to the scientific method, in effect promising to tell the truth, the whole truth, and nothing but — which means that we must include all the doubts, the caveats, the ifs, ands, and buts.

On the other hand, we … need to get some broadbased support, to capture the public’s imagination. That, of course, entails getting loads of media coverage. So we have to offer up scary scenarios, make simplified, dramatic statements, and make little mention of any doubts we might have.

Schneider then offered a “hope.”

This ‘double ethical bind’ we frequently find ourselves in cannot be solved by any formula. Each of us has to decide what the right balance is between being effective and being honest. I hope that means being both.

But by prejudging the enhanced greenhouse effect as highly negative, and by blessing politicization, Schneider doubly violated the science. Meanwhile, more than thirty years later, we are still arguably a decade away—if not more—from getting a firm handle on climate forcings, natural and anthropogenic.

Uncertain Science

The untidiness of climate science regarding fundamental questions has been recognized by alarmists, not only skeptics. James Hansen noted in 1993:

Climate is always changing. Climate would fluctuate without any change of climate forcings. The chaotic aspect of climate is an innate characteristic of the coupled fundamental equations describing climate system dynamics.

And in 1998: “The forcings that drive long-term climate change are not known with an accuracy sufficient to define future climate change.”

Mainstream climatologist Gerald North has repeatedly described uncertain science trying to sort itself out. “There is a good reason for a lack of consensus on the science,” he stated in 1998. “It is simply too early. The problem is difficult, and there are pitifully few ways to test climate models.”

And in 2010 (279):

In another decade of research we will have squared away a lot of our uncertainties about forced climate change. As this approaches we can be thinking about what to do if the warming does indeed appear to be caused by humans and to what extent things are changing as result.

In a Climategate email dated 2009, scientist Kevin Trenberth lamented the state of climate science:

Well, I have my own article on where the heck is global warming… The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t.

Was cloud behavior negating the assumed-to-be strongly positive feedback from the initial warming? Was the heat disappearing into a well-mixed ocean to remain for decades, centuries, or longer? Trenberth admitted “we are nowhere close to knowing where energy is going or whether clouds are changing to make the planet brighter. We are not close to balancing the energy budget….”

Today, climate models are significantly overestimating global warming, suggesting that there is a complicated, subtle answer that only the distant future will know.

IPCC Reports

The United Nations’ Intergovernmental Panel on Climate Change (IPCC) has periodically updated different aspects of the climate change issue, including the physical science. Although the rush to portray “consensus science” has proven controversial, the IPCC reports from inception have indicated great uncertainty and a wide range of estimates from tremulous climate models.

While presenting “climate sensitivity” estimates ranging from benign (1.5ºC) to problematic (4.5ºC) from a doubling of atmospheric CO2, the report stated (1990: xxv) that “climate models give no consistent indication whether tropical storms will increase or decrease in frequency or intensity as climate changes; neither is there any evidence that this has occurred over the past few decades.”

And in the 1995 IPCC report (173): “Overall, there is no evidence that extreme weather events, or climate variability, has increased, in a global sense, throughout the 20th century, although data and analyses are poor and not comprehensive.”

In the third assessment in 2001 (33, 15):

There is no compelling evidence to indicate that the characteristics of tropical and extratropical storms have changed…. For some other extreme phenomena, many of which may have important impacts on the environment and society, there is currently insufficient information to assess recent trends….

And in the fourth assessment (2007: 9, 308):

There is no clear trend in the annual numbers of tropical cyclone activity…. Changes in tropical storm and hurricane frequency and intensity are masked by large internal variability.

Climate models, too, came with words of caution (2007: 805):

[T]he set of available models may share fundamental inadequacies, the effects of which cannot be quantified…. The potential for missing or inadequately parameterized processes to broaden the simulated range of future changes is not clear….

In the most recent (5th) assessment, the IPCC stated (2013: 216):

Current data sets indicate no significant observed trends in global tropical cyclone frequency over the past century and it remains uncertain whether any reported long-term increases in tropical cyclone frequency are robust….

Climate models had “improved” since the prior assessment, but (2013: 824)

every bit of added complexity … also introduces new sources of possible error (e.g., via uncertain parameters) and new interactions between model components that may, if only temporarily, degrade a model’s simulation of other aspects of the climate system…. [S]cientific uncertainly regarding the details of many processes remains.

Models were grappling with a slowdown of surface warming (“the hiatus”) in the last 15 years than the previous 30–60 years (769).

What about today? Two climate scientists wrote in “The Scientific Challenge of Understanding and Estimating Climate Change” (Proceedings of the National Academy of Sciences: December 3, 2019):

The idea that the science of climate change is largely “settled,” common among policy makers and environmentalists but not among the climate science community, has congealed into the view that the outlines and dimension of anthropogenic climate change are understood and that incremental improvement to and application of the tools used to establish this outcome are sufficient to provide society with the scientific basis for dealing with climate change.

Climate Economics

Versus unsettled climate science, the science of plant physiology points toward the direct benefits of carbon dioxide via photosynthesis. Global greening is reason to celebrate, as Matt Ridley recently opined.

CO2 is plant food. The greening of the earth means more food for animals and greater crop yields for humans. Why is no one talking about it?

Another part of settled science is the modest direct warming from CO2 (about 1.2ºC) as compared to feedback effects that are in dispute. Climate economists welcome warmth. “Given that mankind, over the last million or so years, has evolved in climates that were both hotter and colder than today’s,” wrote Thomas Gale Moore in 1998, “how is it that we in the 20th century are so fortunate as to have been born into the ideal global climate?”

In the late 1990s, twenty-six climate economists from 11 universities and three federal agencies were tasked with evaluating the benefits and costs from the IPCC’s “best guess” sensitivity estimate of 2.5ºC and a 7 percent increase in precipitation (forecast to occur in 2060). Study chapters were prepared for agriculture, timber, water, coastal communities (sea level rise), energy, commercial fishing, and outdoor recreation. The assumption was that actors would adapt to change, capitalizing on benefits and mitigating costs.

The overall result, The Impact of Climate Change on the United States Economy (Cambridge University Press: 2009), edited by Robert Mendelsohn and James Newmann, concluded:

  • “The likely warming over the next century is expected to make the US economy better off on average.” (321)
  • “Agronomic studies suggest that carbon fertilization is likely to offset some if not all of the damages from warming.” (ibid.)
  • “Both analysis suggest that a 2.5C warming would result in small market benefits for the United States….” (324)

The public policy conclusions?

  • “The results suggest that aggregate market impacts in the United States are not a motivating favor for near-term action to reduce emissions of greenhouse gases.” (328)
  • “… there is a growing consensus among economists that near-term reductions in greenhouse gases could result in substantial costs.” (1)

Climatologist Gerald North commented:

Mendelsohn … believes the impacts are not negative at all for the US and most of the developed countries. Most impact studies seem to be showing this. It leads us to think that a little warming is not so bad. Glad I have kept my mouth shut on this issue of which I know so little.

This was mainstream analysis at end of the twentieth century—and in the second full decade of the climate alarm—refuting the premise of lawsuits against energy companies and all of us as consumers.

Conclusion

The global warming debate begins—but does not end—with physical science. And a review of mainstream climate science, complemented by mainstream climate economics, unmasks the fallacy of settled alarm in the 1970s, 1980s, and 1990s—and more recently.

Today, the debate over physical climate change roars. If the uncertainties were not great enough within the IPCC, dissident scientists gathered as the Nongovernmental International Panel on Climate Change (NIPCC) have issued their own weighty volumes emphasizing natural, not manmade, climate forcing and the benefits of CO2.

Still, taking the IPCC’s “consensus” at face value, the wide range of sensitivity estimates from the enhanced greenhouse effect, ranging from a positive externality at the lower end to a negative externality at the upper end, awaits further clarification.

 

This article appeared on the Institute for Energy Research website at https://www.instituteforenergyresearch.org/climate-change/unsettled-climate-science-30-years-apace/