Will Happer, Climate Change Denier

July 12, 2019

William Happer is a prominent atomic physicist turned polemicist defender of the virtues of carbon dioxide and naysayer about human-induced climate change. Happer, pictured in Fig. 1, was born in India as the son of a Scottish medical officer, and spent his formative years moving among India, Oak Ridge, Tennessee and North Carolina. He began his academic career at Columbia University, then moved to Princeton University in 1980, where he held the Cyrus Fogg Brackett Professorship in Physics for many years. At both institutions, he developed a strong international reputation for experimental work using the technique known as optical pumping, in which laser light is used to pump atomic or molecular species up into selected excited quantum states.

Will Happer photo
Figure 1.  Will Happer

Happer has served as a long-time member, including a stint (1987-1990) as Chair of the Executive Committee, of the Jason group of prominent scientists that meet annually to carry out (often classified) research and analysis advising various U.S. government agencies on scientific issues of importance to military or other priorities. Happer accepted an invitation to join the Jasons in 1972, while still a post-doctoral assistant at Columbia, after he and others were trapped for a few days inside the Pupin Laboratory by anti-war demonstrators protesting the role of Columbia’s Jason-member faculty in supporting military operations in Vietnam.

Happer made a critical contribution to a mid-1980s Jason assignment to enhance the use of lasers to produce an artificial “guide star” near the top of Earth’s atmosphere, which would facilitate precise corrections for atmospheric distortions in imaging such faint objects as Soviet spy satellites. One result of that work became a crucial element in Ronald Reagan’s proposed Strategic Defense Initiative (SDI) missile defense system in the 1980s. Although Happer’s original work developing adaptive optics was only reported in a declassified version in 1994, it has also become an important technique for improving the quality of imaging by astronomical telescopes.

One of the mysteries of our current political tribalism is how a scientist as respected, clever and discerning as Happer can mutate into a science denier extraordinaire. The latter-day Happer undermines his own calls for dispassionate, fact-based discussion of climate change science with exaggerated polemics illustrated by the following sampling of quotes from him:

This contemporary ‘climate crusade’ has much in common with the medieval crusades [Charles] Mackay describes [in Extraordinary Popular Delusions and the Madness of Crowds], with true believers, opportunists, cynics, money-hungry governments, manipulators of various types, and even children’s crusades.” [Quote from Happer’s 2011 article, The Truth About Greenhouse Gases.]

The demonization of carbon dioxide is just like the demonization of the poor Jews under Hitler. Carbon dioxide is actually a benefit to the world, and so were the Jews.” [Quote from 2014 CNBC interview of Happer.]

“[Concern about climate change is] another one of these sort of mass hysterias that have gripped humanity since it began. In our country, in America, we had a sort of similar case of mass hysteria with Prohibition…More sinister are these movements in Europe: the fascists, the communists. They were mass hysteria too…Any movement can be captured by thugs, and that’s what’s happened.” [Quote from 2015 interview of Happer on the webcast news show Conversations That Matter.]

At the Salem witch trials, every one of those judges had a Harvard degree. Scientific consensus is often wrong.” [From a 2017 Happer seminar at UCLA, as quoted in the Daily Bruin campus newspaper. I suppose it was deference to his home institution that kept him from attributing a Princeton degree to the witch trial judges.]

“…it is high time that we assess great expanses of windmills and solar-panels in the previously unspoiled open spaces of the world with the same objectiveness that we apply to other human perturbations of nature. Looking at once beautiful hilltops, now cluttered with windmills, I am reminded of an exchange between Winston Churchill and a woman who indignantly said, ‘Sir, you are drunk.’ Churchill responded, ‘Madam, you are ugly. In the morning I shall be sober.’ The hilltops will be ugly for a long, long time.” [From the conclusion of The Truth About Greenhouse Gases. Happer claims the mantle of “objectiveness,” but ugliness is in the eye of the beholder. And apparently, he does not consider the excessive burning of fossil fuels as a significant “human perturbation of nature.”]

These quotes, and many more, do not reflect a scientific attitude. We will also show in this post that many of Happer’s allegedly scientific (and hardly original) claims about carbon dioxide and global warming are either irrelevant to the discussion or counter-factual. He remains firmly resistant to the well-documented evidence and counter-arguments that rebut his false claims. Given his training and long experience in the scientific method, he should know better.

But such comments have earned him the (temporary) respect of President Donald Trump, who has recently asked Happer to assemble a Presidential Committee on Climate Security, whose aim would be to cast doubt on the intelligence agencies’ determination that climate change represents a national security threat and on the government’s own 4th National Climate Assessment, which outlined the extreme dangers to U.S. health and economic well-being of the fossil-fuel-burning path we are currently on.

In this post, we will track the stages of Happer’s evolution from respected scientist to climate change naysayer.

Happer’s Early Exposure to Climate Change Concerns

Happer’s initial exposure to the climate science debates likely occurred via Jason group work in the 1970s. Under the leadership of Jason member Gordon MacDonald the group carried out a climate study resulting in a 1979 report on The Long-Term Impact of Atmospheric Carbon Dioxide on Climate. The report presents climate modeling that emphasizes the danger that human burning of fossil fuels would lead to global warming that could outstrip any industrial attempts at cooling. Happer was not a co-author on this study, but his Jason colleague William Nierenberg, then Director of the Scripps Institution of Oceanography, was. Nierenberg and Happer were political allies within the Jason group, both among the group’s “hawks” regarding the Jasons’ advice about Vietnam policy and other military issues. Both would go on to become members of the conservative think tank the George C. Marshall Institute, which was established in 1984 by Nierenberg, Frederick Seitz and Robert Jastrow for the explicit purpose of providing support for Reagan’s SDI initiative.

Nierenberg’s views regarding climate change, which we discuss further below, may have significantly influenced Happer’s. Shortly after the Jason climate study, Nierenberg went on to chair a National Academy of Sciences (NAS) committee of scientists and economists charged with preparing a report on Changing Climate, which had been requested by Congress near the end of the Jimmy Carter administration, but was finally published in 1983 during the Reagan administration.

The 1983 NAS report represented the first comprehensive U.S. look at climate change, including fossil fuel emissions, the carbon cycle, projections of future increases in atmospheric CO2 concentrations, temperatures and sea level, and potential societal and economic impacts. The independently written detailed report chapters are filled with scientific findings that are well in line with decades of subsequent Intergovernmental Panel on Climate Change (IPCC) assessments. Examples of the NAS report’s projections are the following: CO2 concentrations are likely to double by 2065; global mean temperatures would respond to that doubling by rising between 1.5 and 4.5°C, with warming 2 to 3 times as great over the polar regions; sea levels would likely rise by 70 cm by the end of the 21st century but, depending on the extent of melting of polar ice caps, could rise by 5-6 meters over a few centuries.

But the NAS report’s synthesis and Executive Summary, the latter reprinted on the front page of the New York Times the day after the report’s release, also contained words of caution regarding policy recommendations. The report’s synthesis called rising CO2 concentrations a cause for concern, but not panic, and included the following equivocal statement about global accords:

“[J]ust as we as individuals have little incentive to curtail our emissions, we as a nation have little incentive to curb CO2 emissions. By curbing our CO2 output, we make little contribution to the solution and do not know whether we will receive any benefits… Given the need for a widespread long-term commitment, a CO2 control strategy could only work if major nations successfully negotiated a global policy, and while such an outcome is possible, there are few examples where a multinational environmental pact has succeeded.”

The Executive Summary contains the following two quotes, which illustrate the report’s ambivalence regarding government solutions:

We are deeply concerned about environmental changes of this magnitude; man-made emissions of greenhouse gases promise to impose a warming of unusual dimensions on a global climate that is already unusually warm. We may get into trouble in ways that we have barely imagined.”

Viewed in terms of energy, global pollution, and worldwide environmental damage the CO2 problem appears intractable. Viewed as a problem of changes in local environmental factors—rainfall, river flow, sea level—the myriad of individual incremental problems take their place among the other stresses to which nations and individuals adapt.”

The report’s ambivalence thus provided cover for the decision by the Reagan administration to take no action to combat climate change. However, this ambivalence was not very different from that expressed in the preface to the earlier Jason report:

There are numerous uncertainties about the direction and magnitude of anticipated changes. The benefits and costs of these changes to society will depend on the timing and magnitude of the changes and the appropriateness of human responses. Significant uncertainties exist… The uncertainties are great enough to suggest that now is not the proper moment to undertake far-reaching actions designed to mitigate potential effects of increasing CO2.”

There is controversy regarding the specific role that Nierenberg played in inserting these equivocations about policy into both the Jason and NAS reports. Naomi Oreskes and Erik Conway, in Merchants of Doubt and a precursor paper, note that Nierenberg, who was politically conservative, had joined the transition team for the Reagan administration in 1981. By his editing of the NAS report’s synthesis and Executive Summary, Oreskes and Conway argue that “Nierenberg reframed the issue as just one of many changes and challenges facing human society,” and “in doing so arguably launched the climate change debate, transforming the issue from one of scientific concern to one of political controversy.” However, in a 2010 rebuttal paper, Nierenberg’s son Nicolas, with Walter Tschinkel and Victoria Tschinkel, disputes the claims and conclusions of Oreskes and Conway, and argues that the 1983 NAS report reflected no political bias, was fully and wholeheartedly endorsed by all its authors, and was completely consistent with the scientific consensus of the time.

What we do know is that Nierenberg’s skepticism about climate change policy hardened over the ensuing years. Even his son admits: “Later he did become skeptical of the ability of large‐scale climate models to accurately predict the impacts of increasing CO2, and it was his opinion that the likely warming would be on the lower end of the ranges typically discussed. He was also highly skeptical of the political solutions that had so far been proposed at the time of his death in 2000.”

Furthermore, by the end of the 1980s, the Marshall Institute that Nierenberg had co-founded expanded its portfolio beyond SDI support, to cast doubt on the science behind global warming projections. In a 1988 report from the Institute, Nierenberg blamed global warming on solar activity, a claim that has been thoroughly refuted by data. By the 1990s, Marshall Institute scientists Nierenberg, Seitz and Jastrow were leading players in stimulating the conservative backlash against global warming research. They co-authored a 1990 book Scientific Perspectives on the Greenhouse Problem. In 1994, Seitz published a paper entitled Global Warming and Ozone Hole Controversies: A Challenge to Scientific Judgment. The doubt cast upon the work, and even the motives, of climate scientists in Marshall documents was certainly welcomed by the fossil fuel and automobile industries that provided part of the Institute’s funding. This is the environment in which Happer’s views about climate change and the ozone hole controversy began to coalesce.

Happer v. Gore

Happer had a chance to act on his views when he was appointed by President George H.W. Bush in 1991 to the post of Director for the Office of Energy Research within the U.S. Department of Energy. At that point, Happer still had very strong support from the scientific community, and he was easily confirmed to the post by the Senate. Once in the role, he provided strong support to the basic research community in nuclear and particle physics and basic energy sciences. He also oversaw a small portion of the government-funded research into climate change, and expressed consternation that the scientists working on that research were often unable to provide crisp answers to his questions regarding raw data, methods, uncertainties and conclusions.

Happer soon began to run afoul of other government agencies and of the Senate Subcommittee on Science, Technology and Space, which was chaired by then-Senator Al Gore of Tennessee. According to a 1993 news account in Physics Today, the conflicts began to become public in 1992:

Signs of Happer’s heterodoxy on prevailing environmentalist positions first appeared at a meeting of the Federal Coordinating Council on Science, Engineering and Technology [FCCSET] more than a year ago, during the Bush Administration. On that occasion he opposed the apocalyptic vision of an environmentally ravaged Earth, the theme of Gore’s best-selling book, Earth in the Balance: Ecology and the Human Spirit (Houghton Mifflin, 1992). At the meeting Robert T. Watson, then chief scientist for NASA’s Mission to Planet Earth (which uses satellites to study global climate change), delivered a scary account of increases in greenhouse gas emissions that could cause global warming and of exposure to cancer-causing ultraviolet radiation resulting from atmospheric ozone depletion. When Watson spoke of an ‘ozone hole over Kennebunkport,’ President Bush’s summer retreat, Happer, visibly angry according to eye witnesses, interrupted the discourse, calling the concept rubbish, only using a more colorful epithet.”

At that juncture, Happer was still expressing doubts within the spectrum of healthy scientific skepticism, even if they were doubts not shared by a large majority of the scientists working on these subjects. On the ozone hole issue, he sought an endorsement from FCCSET for setting up a network of instruments to measure the discrepancy between predicted and observed levels at Earth’s surface of the dangerous UV-B radiation normally blocked by the stratospheric ozone layer. On climate change, he emphasized that understanding of the interactions that control climate was incomplete and inexact. He objected strenuously to what he saw as overstatements from proponents of government action on both issues. But his disrespect for those proponents grew as he began to tangle more directly with Gore. The staff of the Senate Subcommittee chaired by Gore characterized Happer’s doubts about the extent of greenhouse gas warming as “the Bush White House effect.”

After the 1992 Presidential election, the Clinton-Gore Administration asked Happer to remain at his DOE post until a successor could be named. But as Happer continued to push for more measurements and a delay on any action involving a CFC ban to counteract ozone depletion, he was informed that his advice on the subject was no longer needed. The U.S. Senate had, already in 1988 under President Bush, unanimously ratified the country’s signing of the Montreal Protocol leading to a worldwide ban on CFC production and usage.

At an April 26, 1993 hearing before the House Appropriations Subcommittee on Energy and Water, Happer made explicit and clear his strong disagreements with the environmental policy directions of the new administration, of which he was still a part. He told the Subcommittee: “As an individual I think there has been an exaggeration of the dangers of ozone depletion and climate change.” On ozone depletion, he asserted that data supported very little observed change in UV-B radiation actually reaching the ground. On global warming, he directly contradicted Vice President Gore by insisting that better scientific evidence was needed before any government-sponsored mitigating measures should be enacted. He referenced evidence that Earth had been perfectly habitable during much earlier geologic epochs when atmospheric CO2 concentrations were much higher than they were currently. He had previously argued against Gore’s (ultimately successful) urging that President Clinton announce the fulfillment of a campaign commitment to freeze U.S. CO2 emissions at 1990 levels by the end of the decade. And he seemed to initiate a turf war among agencies when he criticized NASA’s planned Earth Observing System of satellites to monitor climate-relevant properties in the atmosphere, and told the House Subcommittee that his own agency, DOE, was “already engaged in a ‘major initiative’ to improve the scientific understanding of climate change.”

Unsurprisingly in light of these conflicts, Happer was dismissed from his post as DOE Director for Energy Research at the end of May, 1993. At the time, the scientific community was still largely on Happer’s side. The Physics Today news article interprets the news of Happer’s dismissal this way: “Happer’s dispute with Gore’s people is the first instance of the Clinton Administration enforcing its version of ‘political correctness’ on scientists in its midst. The sacking of Happer, a former Princeton University physics professor with impressive credentials, raises questions about whether the Administration will be able to recruit scientists for sensitive positions when science conflicts with politics.”

Happer himself insisted that he was being done in by policy decisions that were based on politics, rather than on science. Having served for two decades by that point as an active member of the Jasons, he could hardly have been shocked that science and politics often intersect. A subsequent letter to the Editor of Physics Today from A.J. Lichtenberg, regarding that news article, pointed out that the distinction is not so clear-cut:

We do not have sufficient knowledge to know for sure what the effect of increased CO2 emission will be, and more research to increase that knowledge is necessary. Both Happer and Gore would surely agree with that statement. The disagreement is about whether or not to impose restrictions on CO2 emissions now. Either decision would be political. Emissions restrictions will put some burden on industry, possibly lowering U.S. competitiveness in some industries. Not restricting emissions will place us in danger of some serious future consequences, such as the melting of ice caps and flooding of coastal cities. The political question is to decide, in the face of uncertainty as to the probability and severity of consequences, which course to take.”

In the wake of his dismissal from DOE, Happer’s skepticism hardened into denial. He took over as Chairman of the George C. Marshall Institute in 2006, until it disbanded in 2015. He then co-founded the advocacy group CO2 Coalition, whose aim is to “educate the public that increased atmospheric levels of CO2 will benefit the world.” The group’s large donors include some of the most ardently conservative foundations in the U.S.: the Sarah Scaife Foundation, the Mercer Family Foundation, the Searle Freedom Trust, and the Lynde & Harry Bradley Foundation. With their support, Happer has been a frequent, outspoken critic of the work done by most of the climate science research community, labeling them with the polemical comments quoted near the start of this post.

Happer seems to have adopted the unshakable belief that those who warn of the dangers of anthropogenic global warming (AGW) are dishonest propagandists, and to have dismissed all the climate research done since the early 90s that supports the reality of AGW. As we will show in the next section, he is now fixated on the fact that human health could absorb much more carbon dioxide in the atmosphere, with no allowance for the climate impacts that are far more important than mere human breathing of CO2. Despite his continuing protestations to the contrary, it is now difficult to see his well-funded resistance as “scientific” rather than “political.”

Perhaps most remarkably, in light of his own public testimony strongly opposing the scientific views of the administration he was part of in 1993, Happer now “supports a controversial crackdown on the freedom of federal agency scientists to speak out about their findings, arguing that mixed messages… have led to people disregarding all public health information,” according to a 2017 profile in The Guardian. How convenient, now that Happer has found an administration that welcomes his idée fixe. The proposed crackdown would ensure that mixed messages will continue, but be based purely on political preferences of the party in power, rather than on peer-reviewable science.

Happer’s False Narratives About CO2

Will Happer has no formal training in, and has published no peer-reviewed articles on, climate science. The fullest exposition of his ideas about climate and CO2 are presented in a paper he wrote for a 2011 issue of the journal First Things, which promotes itself as “America’s Most Influential Journal of Religion and Public Life.” The article, entitled The Truth About Greenhouse Gases, has been reprinted by The Global Warming Policy Foundation. For a scientist reader, the most disappointing aspect of this paper is how little originality is invested in Happer’s claims and arguments, given his considerable innovation in his earlier scientific career. He simply repeats, sometimes embellishing, debunked and specious claims by other climate change deniers. He does not bother to include any figures with data that might support his claims. A paragraph-by-paragraph rebuttal of essentially every point in Happer’s paper has been offered by Michael MacCracken, the Chief Scientist for Climate Change Programs at the Climate Institute in Washington, D.C.

One or two of Happer’s arguments are expanded in a May 2013 op-ed piece, In Defense of Carbon Dioxide, which he co-authored for the Wall Street Journal with former astronaut, Republican Senator and Heartland Institute Board member Harrison Schmitt. A point-by-point critique of that Happer-Schmitt op-ed has also been written, by Shauna Theel of Media Matters. Schmitt’s own views about climate science, by the way, are very clearly influenced by his political outlook, expressed in his 2010 blog: “The previously faint but obvious path of the United States toward national socialism [i.e., Nazism] has suddenly become a super-highway. Reversing direction requires concerted, immediate action in the courts, push-back by the States, and passive resistance by the people…Our concern today should be that ‘regulation’ of individual liberties and ‘control’ of the private sector now has become the often publicly stated goals of the current Congress and President of the United States.”

In what follows, we address here the flaws only in a few central aspects of Happer’s false narrative, aspects we may reasonably expect to see highlighted in any eventual output from Trump’s Presidential Committee on Climate Security to be overseen by Happer. Since these points echo standard climate denier claims, there will be some overlap between our debunking arguments below and those we have offered elsewhere on this site in addressing the Heartland Institute’s book sent to K-12 science teachers throughout the U.S.

1) Happer claims: “Increased CO2 will be good for the planet and will easily outweigh any negative effects.”

This is Happer’s central thesis, and that of his CO2 Coalition. We list below the arguments he uses to support this conclusion, with our own responses in boldface following each of Happer’s claims. For reference, CO2 concentrations in Earth’s atmosphere were roughly 280 ppm (parts per million) in the pre-industrial era and have risen to 415 ppm by 2019, with most of the increase arising over the past half-century (see Fig. 2), in close correlation with increases in the human burning of fossil fuels.

carbon dioxide emissions
Figure 2. A history of worldwide CO2 emissions from fossil fuel burning (blue curve, left-hand axis) and of atmospheric concentrations of CO2 (brown curve, right-hand axis) during the industrial age. Current emissions are about 36 billion metric tons per year and concentrations are 415 ppm, with both still growing rapidly.
  • “…atmospheric CO2 levels should be above about 150 ppm [parts per million] to avoid harming green plants and below about 5000 ppm to avoid harming people.” The upper limit Happer quotes is based on NASA studies of the long-term limits on human breathing for healthy astronauts. This is hardly relevant, as great harm to human well-being will arise from other properties of CO2 – such as its absorption of infrared radiation emitted by the Earth — at much lower concentrations. Happer’s thesis here is the rough equivalent of telling humans that food is good for them, and their stomachs will not burst until they’re consuming 100,000 calories per day. So they should all be eating much more than they are currently. Never mind the serious health problems related to obesity that set in at far lower caloric intakes.
  • About fifty million years ago, a brief moment in the long history of life on earth, geological evidence indicates, CO2 levels were several thousand ppm, much higher than now. And life flourished abundantly.” Of course, there was no human life at that point, and certainly nothing like the population density of humans that characterizes our current situation. The inexorable rise of sea levels associated with ongoing global warming induced by greenhouse gas concentrations will end up causing massive human migrations from coastal areas, and we’ve gotten a glimpse over the past several years into how poorly human civilizations adjust to massive influxes of foreigners. Furthermore, evolution allows adaptation of species to gradual environmental changes, including higher greenhouse gas concentrations. But what we are currently seeing is not at all gradual, it is on track to double greenhouse gas concentrations over just a few human generations. The closest analog in the geologic history of the Earth arose from periods of intensive volcanic eruptions that spanned a few millennia, and are closely correlated with Earth’s known periods of mass extinctions. As emphasized by Ken Caldeira, a paleoclimate expert at Stanford University: “Atmospheric CO2 concentrations have never risen so much so rapidly as they are today without being accompanied by a mass extinction event. The geologic record gives us no reason to be sanguine about current rates and amounts of CO2 increase.”
  • Plants grow better and have better flowers and fruit at higher CO2 levels. Commercial greenhouse operators recognize this when they artificially increase the CO2 concentrations inside their greenhouses to over 1000 ppm.” Commercial greenhouses are controlled environments, in which operators also maintain temperatures, water availability and other nutrient (e.g., nitrogen) supplies within optimal ranges. The planet is not a controlled environment, and rapidly increasing greenhouse gas concentrations in the atmosphere will lead to changes in climate and soil properties that will harm agricultural productivity over many parts of the planet, while some regions may benefit in the short term.  For example, a 2019 IPCC Special Report on Climate Change and Land notes that: “A recent meta-analysis shows that experimental CO2 enrichment generally results in lower nitrogen and phosphorus concentrations in plant tissues…reduced responses to elevated CO2…result from complex interactions of ecosystem factors that influence nitrogen acquisition by plants.” The fact that human-induced emissions of greenhouse gases have led to a steady increase in atmospheric concentrations over the past half-century (see Fig. 2) is evidence that all the vegetation on Earth cannot absorb the extra CO2 we’re pumping out. We are upsetting the delicate environmental balance, illustrated schematically in Fig. 3 for a moment during the 1990s (it’s much worse now). Many countries are currently investing heavily in reforestation projects to try to increase CO2 absorption capacities.
carbon cycle
Figure 3. Worldwide emissions (upward arrows) and absorption (downward arrows) of CO2 during the 1990s. Fossil fuel burning emissions are currently up to 36 billion metric tons per year and still rising rapidly. Furthermore, the rate of emissions from the oceans increases as the oceans warm.
  • Happer and Schmitt amplify the latter point in their 2013 op-ed, where they claim that increased levels of CO2 in the air lead to evolutionary change that “decreases the amount of water that the plant is forced to transpire and allows the plant to withstand dry conditions better. Crop yields in recent dry years were less affected by drought than the crops of the dust-bowl droughts of the 1930s, when there was less carbon dioxide. Nowadays, in an age of rising population and scarcities of food and water in some regions, it’s a wonder that humanitarians aren’t clamoring for more atmospheric carbon dioxide.” This oversimplified argument simply ignores the broader array of climate impacts indicated by far more sophisticated analyses of increasing greenhouse gas concentrations. Global climate modeling carried out by the IPCC shows that the temperature increases accompanying growing greenhouse gas concentrations will lead (indeed, are already leading) to increased evaporation, decreased soil moisture, greater crop water demand, more erratic precipitation patterns and more extreme climate events, such as heat waves, floods and droughts. Those regions now suffering food and water scarcity are likely to be the most seriously affected. NASA simulations available when Happer and Schmitt were writing their op-ed indicate that “wet regions of the world, such as the equatorial Pacific Ocean and Asian monsoon regions, will see increases in heavy precipitation because of warming resulting from projected increases in carbon dioxide levels. Arid land areas outside the tropics and many regions with moderate rainfall could become drier.” An analysis carried out by W.R. Cline for the World Bank Climate-Smart Agriculture program cites IPCC studies that “point to severe crop yield reductions in the next decades without strong adaptation measures – particularly in sub-Saharan Africa and South Asia. These are areas where rural households are highly dependent on agriculture and farming systems are highly sensitive to volatile climate. One assessment estimates that by the 2080s world agricultural productivity will decline by 3-16%. The loss in Africa could be 17-28%.” The projected regional impacts on agricultural productivity of global mean temperature increases by 1-3°C are indicated in Fig. 4. If temperatures increase by even more than 3°C, then even those northern regions that appear to benefit in Fig. 4 will likely see climate-driven deterioration in the length of growing seasons and in agricultural productivity.
Figure 4. Projected changes, by region, in agricultural productivity by 2080 if global temperatures rise by 1 to 3 degrees C, from Cline (2007).
  • Now the Environmental Protection Agency wants to regulate atmospheric CO2 as a ‘pollutant.’ According to my Webster’s New Collegiate Dictionary, to pollute is ‘to make or render unclean, to defile, to desecrate, to profane.’ By breathing [out CO2] are we rendering the air unclean, defiling or desecrating it?This is another misdirection by Happer. The relevant definition of “pollutant” is not Webster’s, but rather that in the U.S. Clean Air Act (CAA) that governs EPA policies with respect to the atmosphere. The CAA identifies covered pollutants as air components “which may reasonably be anticipated to endanger public health and welfare.” The U.S. Supreme Court in Massachusetts v. EPA has long since decided that, at elevated concentrations, “greenhouse gases fit well within the CAA’s capacious definition of air pollutant…” Even the Trump Administration’s EPA is not contesting that ruling.

2) Happer claims: “The supposed reason for limiting CO2 is to stop global warming—or since the predicted warming has failed to be nearly as large as computer models forecast—to stop climate change.”

Here, Happer parrots standard denier claims that there is no significant global warming and that climate change is not producing any serious noticeable effects. Again, we debunk each aspect of this argument below.

  • Climate models have dozens of parameters, not unlike the epicycles of Ptolemaic astronomy. And they have done poorly at predicting the future. No model predicted the lack of net warming of the earth’s temperature that we have experienced over the past ten years.” Since about 1970 the average observed global warming trend has been an increase by approximately 0.2°C per decade. Superimposed on this trend there are annual fluctuations of amplitude on the order of 0.2°C that arise from volcanic activity, el niño, polar vortex, solar cycles, and the like. These fluctuations are difficult to predict long in advance. Hence, it is always possible to cherry-pick a decade in which year-to-year events conspire to give little net change in global mean temperatures. The red circle in Fig. 5 highlights the particular decade climate change deniers have uniformly focused on to discredit models of the human effect on global temperatures. But as the data before and since clearly demonstrate, global mean temperatures have continued to rise for more than a half-century, at a rate quite consistent with climate model predictions. Furthermore, Happer completely neglects the steady increase in the amount of heat energy stored in Earth’s oceans. Most observed consequences of global warming have in fact fallen near or above the upper end of uncertainty ranges associated with predictions of global climate models.
anomalous decade
Figure 5. The observed changes in global mean temperature since 1880. The red circle encloses the decade many climate change deniers have highlighted to discredit the concept of human-caused global warming.
  • Climate change itself has been embarrassingly uneventful, so another rationale for reducing CO2 is now promoted: to stop the hypothetical increase of extreme climate events like hurricanes or tornados. But dispassionate data show that the frequency of extreme events has hardly changed and in some cases has decreased in the 150 years that it has taken CO2 levels to increase from 270 ppm to 390 ppm.” This is a simple falsehood that ignores the growing number of people that have lost loved ones and property to extreme climate events. The dispassionate actuarial data in Fig. 6 show clearly that the frequency of severe storms, floods, droughts, extreme weather events and forest fires – all predicted to be correlated with climate change in climate models – has tripled since 1980, as greenhouse gas concentrations and heat stored in Earth’s oceans have risen steadily (warmer oceans spawn more severe storms). The same plot illustrates that the frequency of catastrophes, such as volcanic eruptions, earthquakes and tsunamis, that are not attributable to climate change, has remained steady during the same period of time.
Munich RE disaster statistics annotated
Figure 6. Actuarial data recorded by the world’s largest reinsurance company Munich RE since 1980 on the annual number of severe natural loss events, which cause fatalities and/or substantial monetary loss, of various types. The statistics are updated annually at Munich RE’s NatCatService site.
  • The argument starts something like this. CO2 levels have increased from about 270 ppm to 390 ppm over the past 150 years or so, and the earth has warmed by about 0.8°C during that time. Therefore the warming is due to CO2. But correlation is not causation. The local rooster crows every morning at sunrise, but that does not mean the rooster caused the sun to rise.” This is more multi-faceted misdirection by Happer. As seen clearly in Fig. 5, global mean temperatures have risen by 1.0°C over 50, rather than 150, years when the emissions of greenhouse gases have been most severe. The argument is not simply based, as Happer implies even though he knows better, on observed correlation alone, but rather on the well understood physics that greenhouse gases in the atmosphere absorb infrared radiation emitted by the Earth and re-radiate much of it back toward Earth’s surface, thereby altering the balance between power input to and output from the Earth, and consequently increasing Earth’s temperature. Indeed, correlation does not prove causation. But the past 50 years have seen: CO2 emissions double; atmospheric CO2 concentrations rise by 25%; global surface temperatures rise by 1°C, and by much more in many Earth regions; the heat stored in Earth’s oceans increase by 2 x 1023 Joules, roughly equivalent to 300 years’ worth of worldwide energy consumption at present rates; sea levels rise by 10 cm, with the rate of rise accelerating; severe storms, droughts, floods and forest fires triple in frequency; Arctic and Antarctic ice melt rates increase 6-fold; and so forth. These are all impacts consistent with global climate model projections, and no convincing alternative explanations to human-caused greenhouse gas emissions have been offered. If this much correlation doesn’t cause you concern, you’re either not paying attention or being paid to ignore the issue.

3) Happer claims: “The earth’s climate has always been changing. Our present global warming is not at all unusual by the standards of geological history, and the mild warming is probably benefiting the biosphere. Indeed, there is very little correlation between the estimates of CO2 levels in the atmosphere and the estimates of the earth’s temperature over the past 550 million years.”

The true part of this statement is that Earth’s climate has indeed gone through many changes over geologic history, and that greenhouse gas concentrations are just one among a number of climate drivers. However, the implication that the ongoing changes are in no way unusual, and that there is little evidence of correlation between past CO2 levels and global temperatures, is another part of the standard climate change denier’s false narrative. We address each of Happer’s supporting claims below.

  • Our present global warming is not at all unusual by the standards of geological history.” The magnitude of the temperature changes we’ve seen are not unusual, but the rate of global temperature rise is certainly unusual. Happer lists a number of other drivers of Earth’s climate, but all are characterized by time scales very different – either much longer, in the case of changes to Earth’s orbit around the Sun, or much shorter-term fluctuations, in the case of volcanoes or shifts in ocean currents – from what we’re seeing now. The rapid steady rise in global mean temperatures is occurring on time scales that are short compared to human evolutionary or mass migration movements.
  • A rare case of good correlation between CO2 levels and temperature is provided by ice-core records of the cycles of glacial and interglacial periods of the last million years or so. But these records show that changes in temperature preceded changes in CO2 levels, so that CO2 levels were an effect of temperature changes.Happer here refers to a detailed record showing extremely strong correlation between temperatures and CO2 (as well as methane) concentrations over a time interval of 800,000 years as “a rare case of good correlation.” Elsewhere he suggests we should really consider the geologic record going back 550 million years. He neglects to mention that our Sun, like all so-called “main sequence” stars, increases its own temperature and power emission as it burns its hydrogen fuel, so that 550 million years ago Earth would have been receiving several percent less energy from the Sun, making an increased greenhouse “blanket” around Earth quite welcome then, in contrast to now. And he oversimplifies the cause-effect relationship associated with temperature rise during interglacial periods. The initial driver on the emergence from ice ages is Earth orbital changes, but one cannot account for the extent of the interglacial temperature rise over millennia from that driver alone. Models that can explain the details of the temperature rise during emergence from the most recent ice age 20,000 years ago attribute most of the eventual warming to the secondary greenhouse effect of CO2 released into the atmosphere from oceans that were first warmed by the primary driver of orbital change. So increased CO2 concentrations were both effect and cause of the temperature changes.
  •  “There is no evidence for significant increase of CO2 at the Medieval Warm Period, nor for a significant decrease at the time of the subsequent Little Ice Age.Reconstructed temperature records shown in Fig. 7 do, indeed, reveal a global warming by a few tenths of a degree during the so-called Medieval Warm Period from about 500 to 1200 AD, and a global cooling of similar magnitude during the Little Ice Age from about 1400 to 1800. These changes do not seem to have been caused by changes in greenhouse gas concentrations. But as also revealed in Fig. 7, the rate of temperature change during these historical periods does not compare to the current trend seen since 1900, and especially over the past half-century. As noted above, the ongoing warming is strongly correlated with measured increases in greenhouse gas concentrations of known origin and predicted effect within global climate models that do a pretty good job of explaining the observations.
global temps
Figure 7. The history of mean northern hemisphere temperatures since the year 200, as estimated from a variety of different analyses represented by the different colored bands.

4) Happer claims: “Other things being equal, doubling the CO2 concentration, from our current 390 ppm to 780 ppm will directly cause about one degree Celsius warming.”

Happer is here acknowledging the basic physics that makes clear that increased greenhouse gas concentrations contribute to warming, while intimating that the effect is no cause for concern by his careful use of the word “directly.” Skeptics and proponents alike agree that the primary effect of the greenhouse “blanket” would increase global mean temperatures by about 1.2°C for a doubling of pre-industrial CO2 concentrations from 280 to 560 ppm (not from 390 to 780, as Happer claims). What climate models attempt to account for are the multiple secondary feedback effects that result from this primary effect, and either amplify it (positive feedback) or counteract it (negative feedback). Again, we consider each of Happer’s supporting arguments below.

  • But there is observational evidence that the feedback factor is small and may even be negative. Climate models appear to fit the temperature rise over the last 150 years very well. But the values of various parameters like clouds and the concentrations of anthropogenic aerosols are adjusted to get the best fit to past observations.” Happer does not provide any reference to or comment on the so-called “observational evidence” that the feedback factor is small or negative. He makes it sound like “fudging” that model parameters are adjusted to fit past observations, when he knows fully well that is a characteristic of all scientific models, preceding the establishment of some more fundamental theory that might predict the parameter values. He fails to mention several of the most important feedback mechanisms that would affect not only the current situation, but also the historical glacial cycles recorded in ice samples (long before “anthropogenic aerosols” were a concern), independent of whatever caused the primary temperature change. These feedback mechanisms include: (a) the warmer atmosphere holds more water vapor, which also acts as a greenhouse gas, amplifying the temperature rise; (b) warmer oceans will release more CO2, since it becomes less soluble in warmer water; (c) rising surface and water temperatures melt more polar ice, reducing the reflection of incident sunlight, and thereby amplifying the temperature increase; (d) thawing Arctic permafrost releases more methane, which also acts as a greenhouse gas to amplify the warming. Without inclusion of such positive feedback effects, it is not possible to account for the observed temperature rises in the emergence from past ice ages. Analyses of those periods indicate that a primary temperature increase of 1.2°C would be amplified by feedback to somewhere between 2 and 4.5°C, or roughly 3°C on average, in contradiction to Happer’s claim of minimal positive, and perhaps even negative, overall feedback. Claims that CO2 increases don’t cause much temperature increase, and that feedback mechanisms are not important or are predominantly negative, are generally based on oversimplified models that are unable to account for the historical climate changes to which global climate models are calibrated.
  • “…the main problem with models could well be their treatment of clouds and water vapor, changes of which can affect the earth’s temperature as much or more than changing levels of CO2.” The feedback effect of clouds is, indeed, complicated. A warmer atmosphere supports greater cloud formation. More clouds then reflect more of Earth’s infrared emissions back toward the surface, increasing warming, but they also reflect more of the sunlight incident from above, thereby cooling the Earth. Uncertainties in the treatment of these and other feedback effects lead to specified uncertainties in the projections made with global climate models. But the entire range of projections within those uncertainty bands indicate a dangerous warming resulting from the steady increase in emissions of CO2 and other greenhouse gases, arising primarily from human activities. Sea levels have risen during this century at a rate at the upper end of climate model predictions, and Arctic and Antarctic ice melt has been occurring at rates exceeding even the most pessimistic model predictions.
  •  “Yet the models have failed the simple scientific test of prediction. We don’t even have a theory for how accurate the models should be.” Happer reiterated this point in a different context in a short 2018 piece in Range magazine: “I know the difference between real and phony science. My sodium guide stars work. Climate models do not.” The models have not failed the test of prediction. Happer’s claim here is based on the cherry-picked decade highlighted in Fig. 5, where year-to-year fluctuations beyond model prediction capabilities conspired to temporarily stabilize temperatures. He continued to make the same claim in 2018, when that anomalous decade had receded in the rear view mirror. He supported his argument by the further counter-factual claims that “The rates of sea level rise have not accelerated. The weather has not become more extreme.” Furthermore, his statement that “we don’t even have a theory” is made to suggest that getting a theory is the starting point of any serious analysis. It is not. Global climate is a highly complex system with many drivers, interacting parts, and feedback mechanisms. These are reasons for skepticism and for modeling with adjustable parameters tuned to reproduce past observations. But they are not reasons to discredit the implication of all credible models that warming is significant, caused predominantly by human activities and likely to have severe consequences if left unchecked. The issue goes back to the statement made in the letter to the Editor of Physics Today, quoted above: “The political question is to decide, in the face of uncertainty as to the probability and severity of consequences, which course to take.” Discrediting the science underlying the question cannot get one to a sensible answer. If the countries of the world were to wait until there is a more fundamental underlying theory of global climate, it would be far too late to act to avoid severe consequences – that delay, after all, is the real aim of climate change deniers.

5) Happer claims: “A major problem has been the co-option of climate science by politics, ambition, greed, and what seems to be a hereditary human need for a righteous cause. What better cause than saving the planet, especially if one can get ample, secure funding at the same time? Huge amounts of money are available from governments and wealthy foundations for climate institutes and for climate-related research.”

Happer’s implications here that (a) the thousands of climate scientists who have participated in the IPCC and U.S. national models and assessments of global climate are all in it for the money or the glory, while (b) climate change deniers are pure of motive and starved of support by wealthy foundations, simply do not wash. Here are a couple of his related arguments:

  •  “…a government contract becomes virtually a substitute for intellectual curiosity.” So insists the pure scientist no longer sullied by a government contract. This innuendo is both false and insulting. Happer’s rehash of numerous already debunked denialist claims hardly manifests unfettered intellectual curiosity at work.
  •  “Skeptics’ motives are publicly impugned; denigrating names are used routinely in media reports and in the blogosphere; and we now see attempts to use the same tactics that Big Brother applied to Winston Smith in Orwell’s 1984.” A curious claim from a scientist who has compared climate researchers who warn of serious global warming consequences to hysterics, opportunists, thugs and Nazis.
  • ’Mitigation’ and control efforts that have been proposed will enrich a favoured few with good political ties—at the expense of the great majority of mankind, including, especially, the poor and the citizens of developing nations.” Happer’s concern for the poor and developing nations is touching, but based on a hidden assumption that the buildup of electricity supply infrastructure in developing nations will necessarily be much more expensive for abundant renewable energy sources than for fossil fuel burning. That is far from obvious, on the time scales on which those infrastructure buildups will occur. Furthermore, there is a clear template in the Montreal Protocol for global environmental accords that allow developing nations to meet guidelines on a longer time scale than wealthy nations. But such accords require that the leaders of wealthy nations not complain that their own countries are getting ripped off by committing to more stringent timelines and conditions, and by offering financial contributions to aid the compliance by developing countries. And what if Happer and his fellow-travelers happen to be wrong? If global warming continues on its projected trend, it is precisely the poor and developing nations who will bear most of the brunt of rising seas and deteriorating food supplies. In fact, if climate change deniers really want to help developing nations, perhaps they should voluntarily relocate to poor island nations at risk of submersion under rising seas, to lead adaptation efforts there. Finally, it seems unlikely that Happer’s concern for the poor and developing nations is shared by the wealthy conservative foundations and fossil fuel companies that have supported the George Marshall Institute and his CO2 Coalition.

Nobody is suggesting that formulating policies to address climate change will be an easy process (see our post on Climate Change Problem Solving). What I am suggesting is that it is a fundamentally dishonest process when many politicians base their stances on views expressed by a tiny minority of scientists, like Happer, who expend lots of energy questioning the underlying science, but no energy actually listening to the answers. Politics and science have become inextricably intertwined on this issue, but we have a responsibility to subject the arguments made by both sides to intellectual scrutiny. Happer’s claims do not withstand that scrutiny.

Will Happer must know that many of the arguments made on behalf of his CO2 Coalition are either false or seriously misleading. He deliberately mis-characterizes data that clearly point to serious warming trends. Happer’s conclusions have remained unchanged over the past two decades, as he continues simply to ignore the accumulating wealth of evidence that points to anthropogenic global climate change. His characterizations of mainstream climate scientists and their motives are shocking and grossly exaggerated. Dr. Happer has abandoned any attempt to provide an objective and even-handed review of climate change.




Ann Finkbeiner, The Jasons: The Secret History of Science’s Postwar Elite (Penguin Books, 2006), https://www.amazon.com/Jasons-Secret-History-Sciences-Postwar/dp/0143038478


W. Happer, The Truth About Greenhouse Gases, https://www.thegwpf.org/images/stories/gwpf-reports/happer-the_truth_about_greenhouse_gases.pdf

M.C. MacCracken, The Real Truth About Greenhouse Gases and Climate Change, http://www.climatesciencewatch.org/wp-content/uploads/2011/09/The-Real-Truth-About-Greenhouse-Gases-and-Climate-Change.pdf


W. Happer, Climate Science Fiction (Range Magazine, 2018), https://web.archive.org/web/20190220232116/http://www.rangemagazine.com/features/summer-18/range-su18-climate_science_fiction.pdf







Changing Climate: Report of the Carbon Dioxide Assessment Committee (National Academies Press, 1983), https://www.nap.edu/catalog/18714/changing-climate-report-of-the-carbon-dioxide-assessment-committee


N. Oreskes and E. Conway, From Chicken Little to Dr. Pangloss, https://web.archive.org/web/20130720101043/http:/history.ucsd.edu/_files/base-folder1/From%20Chicken%20Little%20to%20Dr.%20Pangloss.pdf

N. Nierenberg, W.R. Tschinkel and V.J. Tschinkel, Early Climate Change Consensus at the National Academy: The Origins and Making of Changing Climate, http://scilib.ucsd.edu/sio/hist/nierenberg_early-climate-change-consensus.pdf









IPCC Special Report on Climate Change and Land (2019), https://www.ipcc.ch/report/srccl/








J.D. Shakun, et al., Global Warming Preceded by Increasing Carbon Dioxide Concentrations During the Last Deglaciation, Nature 484, 49 (2012), https://www.nature.com/articles/nature10915