Much of the fear of global warming, now called climate change, stems from long-term projections that use complex climate models. These are correctly called projections, not predictions, because none of the models has undergone the rigorous scientific testing required for verification and validation. Consequently, the models and their results are speculative. If a climate model had been verified and validated, that would be the only model needed. As it is, we have multiple models producing a wide variety of projections. A critical issue in global warming/climate change science is the reliability of the models and the evidence substantiating their use.
Recent History of the Global Warming Guess
The fear of human-caused global warming really started in the late 1970s. Based on the best surface-temperature data available at the time, global temperatures had been falling from 1940 to the mid-1970s, creating fears of another ice age. (See “Hot and Cold Climate Apocalypses,” nearby.) About 1977, temperatures suddenly rose. At the time, the reasons for this sudden increase were not known.
Some scientists suggested the cause of the sudden warming was an increase in carbon dioxide, and other greenhouse gases, brought about by the Industrial Revolution. During the Industrial Revolution, the burning of wood and other traditional materials for fuel was replaced by the burning of coal and later oil and natural gas—so-called fossil fuels. Use of fossil fuels increased significantly during the prosperous post-World War II period, as part of a significant improvement in people’s living conditions. The result was an increase of carbon dioxide (CO2) in the atmosphere, leading many scientists to suspect the globe may be warming due to carbon dioxide.
The U.S. National Academy of Sciences had an eminent panel of experts examine the claims of possible warming from carbon dioxide and other greenhouse gases. The panel, called the Climate Research Board, was headed by the noted meteorologist Verner Suomi, considered the father of satellite meteorology. The Climate Research Board appointed an ad hoc study group to examine impact the of greenhouse gases on the earth’s temperatures. The study group was headed by the noted American meteorologist Jule G. Charney, who played an important role in developing numerical weather prediction and was Alfred P. Sloan Professor of Meteorology at the Massachusetts Institute of Technology.
Their report was published in 1979 by the National Academy of Sciences and is called the Charney Report. 1 It estimated that “the most probable global warming for a doubling of CO2” would be roughly 6 degrees Fahrenheit, with a probable error of plus or minus 3 degrees. But the devil is in the details. Repeated laboratory experiments, such as ones at the U.S. National Bureau of Standards, demonstrated that a doubling of CO2 would lead to a modest increase in temperatures. Modern instruments probably would not be able to detect the influence of CO2 on temperatures that is separate from natural variation in temperatures. The climate has been warming and cooling for hundreds of millions of years, long before humanity evolved, much less before the Industrial Revolution. For the past 2.5 million years, the earth has been in a cold period with lengthy ice ages, interrupted by brief warm periods of 10,000 years or so. We are about 10,000 years into the current warm period called the Holocene.
The Charney Report stated that numerical modelers of global climate had estimated that the modest warming caused by carbon dioxide would be greatly amplified by a more powerful warming from an increase in water vapor, particularly in the tropics. Though few people realize it, water vapor is the dominate greenhouse gas on earth. At the time of the 1979 report, there were no comprehensive measurements of global atmospheric temperatures, or water vapor, to confirm or deny this educated guess that water vapor would cause a more powerful warming. Measurements by weather balloons, the main method used to measure temperatures at the time, only test a small sliver of the atmosphere and are far from comprehensive.
Thus, according to the Charney Report, human-caused greenhouse gas warming has two components, both of which occur in the atmosphere. The first component is directly from increased carbon dioxide and is estimated from laboratory experiments to be modest. The second component of human-caused global warming is indirect—a positive feedback from increased atmospheric water vapor—and would be far more powerful than the direct warming from carbon dioxide, but would also occur in the atmosphere.
In 1979 scientists lacked any comprehensive measurements of atmospheric temperatures, so the Charney Report’s guesses could not be confirmed or denied. But to cause this “top-down warming,” the warming trends in the atmosphere would have to be more pronounced than surface warming trends, because much of the energy from atmospheric warming is lost into space and does not affect surface temperatures.
In 1988, the U.N. formed the Intergovernmental Panel on Climate Change (IPCC). It was set up “to prepare, based on available scientific information, assessments on all aspects of climate change and its impacts, with a view of formulating realistic response strategies.” According to its governing principles, the IPCC is “…to assess on a comprehensive, objective, open and transparent basis the scientific, technical and socio-economic information relevant to understanding the scientific basis of risk of human-induced climate change, its potential impacts and options for adaptation and mitigation. IPCC reports should be neutral with respect to policy, although they may need to deal objectively with scientific, technical and socio-economic factors relevant to the application of particular policies.”2
In its first assessment report, the IPCC provided no new data regarding the cause of the temperature increase in the late 1970s or the relationship between increasing CO2 and global warming. But it did play a decisive role in creating “the key international treaty to reduce global warming and cope with the consequences of climate change.”
That treaty, called the U.N. Framework Convention on Climate Change (UNFCCC), was agreed upon at the Earth Summit in Rio de Janeiro in 1992. President George H.W. Bush signed it, and the Senate ratified it with stipulations. The treaty entered into force in 1994. The treaty’s principal objective was “stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic [i.e., man-made] interference with the climate system.” The UNFCCC holds annual meetings called the Conference of Parties (to the treaty).3
Measuring Atmospheric Temperatures
The international agreements forming the IPCC and the UNFCCC were designed to prevent greenhouse gas warming of the atmosphere, and as those agreements were hammered out, two American scientists, Roy Spencer and John Christy, developed a method that uses data collected from weather satellites to produce science’s first comprehensive measure of global atmospheric temperatures.
The value of measuring atmospheric temperatures globally becomes clear when we recall that the untested hypothesis behind global warming projects that greenhouse gas warming in the atmosphere will cause the surface to warm by 6 degrees Fahrenheit (with a probable error of plus or minus 3 degrees). For atmospheric warming to cause surface warming, atmospheric warming trends need to be far more pronounced than the surface warming trend.
The Spencer-Christy method of determining global atmospheric temperatures uses weather satellites, which do not directly measure temperature; instead, they measure radiant energy in various wavelengths. The energy must then be mathematically converted to obtain calculations of temperature. The process is similar to using an ear probe in a doctor’s office to calculate a person’s temperature.
Since December 1978, the National Oceanic and Atmospheric Administration’s polar-orbiting satellites have measured upwelling microwave radiation from atmospheric oxygen, and Spencer and Christy use this data to calculate the temperature of broad volumes of the atmosphere. Thanks to their work, we have comprehensive atmospheric temperature dating to December 1978. The records are kept electronically and are publicly available, including any adjustments, at the National Space Science & Technology Center of the University of Alabama in Huntsville.
Although there have been minor errors in calculations, such as early failure to adjust for orbital decay of the satellites, once recognized, the data have been quickly adjusted, as is expected in rigorous science. For developing this method to calculate atmospheric temperatures from satellite data, Spencer and Christy have been awarded NASA’s Medal for Exceptional Scientific Achievement. Today, the data from satellites is converted to temperature data by three independent groups, which cross-check each other. Further, the temperature calculations are independently confirmed by four different sets of weather balloons that measure atmospheric temperatures using thermometers.
The global average temperature calculations cover 97-98 percent of the earth’s surface, excluding only the most extreme polar latitudes. Obviously, lower atmospheric measurements are not possible in land areas with an elevation above 4,500 feet, but upper atmospheric measurements are available for these areas.
As the Spencer-Christy method to measure atmospheric temperatures was being developed—a method that would permit scientists to test the greenhouse gas warming hypothesis in the Charney Report—international organizations did not wait to act. They were being mobilized to control greenhouse gases that the untested hypothesis of the Charney Report guessed would cause global warming. The international solution proposed was to control emissions of carbon dioxide.
Yet a conflict arose among scientists over the question of whether the Charney Report’s hypothesis had been adequately tested, and the dispute became very public because governmental organizations with large public funding were involved. The conflict, in other words, was and remains largely political, not scientific, and it is financed by governments. The U.S. government is heavily involved in financing the guess that greenhouse gas warming will be dangerous, based on the untested hypothesis. At the same time, independent research efforts are producing evidence that calls into question the fear of global warming from greenhouse gases.
Independent researchers have tested the Charney Report’s hypothesis against atmospheric temperature data, which now extends over 37 years, and found the hypothesis wanting. The Report’s assumptions are simply not supported by empirical observation of nature. The hypothesis needs to be modified or discarded. As Richard Feynman, a Nobel laureate in physics, liked to say, “It doesn’t matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn’t agree with experiment, it’s wrong.”
From Warming Fears to Cooling Claims
The lack of significant warming in recent years has become such an embarrassment that many desperate persons are now abandoning the term “global warming” in favor of the term “climate change,” in hopes they can somehow connect carbon dioxide to cooling global temperatures. Yet there is no generally accepted scientific hypothesis that posits any way for greater carbon dioxide levels in the atmosphere to cause cooling. In addition, some political advocates of climate alarmism have invented the claim that increased carbon dioxide will worsen extreme weather events like hurricanes, but this, too, has no basis in broadly accepted theory or in empirical observation. As the Swedish climate scientist Lennart Bengtsson has written, “there are no indications of extreme weather in the model simulations, and even less so in current observations.”4 Bengtsson is an internationally known Swedish meteorologist. His research includes the sensitivity of climate to CO2, extreme weather events, climate variability, and climate predictability.
Similarly, professor Roger Pielke Jr. of the University of Colorado, Boulder, has published extensively on extreme weather, including at the center-left website FiveThirtyEight.com run by Nate Silver. He writes, “There is scant evidence to indicate that hurricanes, floods, tornadoes or drought have become more frequent or intense in the U.S. or globally.” But in the same article he observes that even though the U.N. IPPC backtracked on earlier claims related to extreme weather, he and his findings were attacked by the Obama White House and by the Center for American Progress, which was founded by Hillary Clinton’s 2016 campaign chairman, John Podesta.5 After WikiLeaks published thousands of Podesta’s emails, Pielke discovered an email6 in which a staffer at CAP bragged to a donor, hedge fund billionaire Tom Steyer, that CAP’s website had forced Nate Silver to ban Pielke from FiveThirtyEight.com. Steyer has been the largest individual donor in American politics for the last two election cycles, giving over $91 million in the 2016 cycle.7 Given the way Steyer has focused his giving on environmentalist causes of the left, Steyer’s inspiring CAP to squash scientific discussion provides support for Robert Brulle’s view that rich donors can distort public perceptions of climate science.
The failure to find physical evidence that supports the Charney Report’s assumptions does not stem from any lack of funding—from both governmental and private sources—in strong support for projects trying to find such evidence. For details on the tens of billions spent on scientific research and political advocacy, see the nearby reports.
Kenneth Haapala is president of the Science and Environmental Policy Project and a contributor to the reports of the Nongovernmental International Panel on Climate Change (NIPCC). He is an energy and economics modeler and past president of the oldest science society of Washington.
- Roger Pielke Jr., “My Unhappy Life as a Climate Heretic,” Wall Street Journal, Dec. 2, 2016, https://www.wsj.com/articles/my-unhappy-life-as-a-climate-heretic-1480723518