Manipulation of Global Warming Science

Published Mar 19, 2007

NOTE: The following is one of a series of case studies produced by the Union of Concerned Scientists' Scientific Integrity Program between 2004 and 2010 to document the abuses highlighted in our 2004 report, Scientific Integrity in Policy Making.

Since taking office, the George W. Bush administration has consistently sought to undermine the view held by the vast majority of climate scientists that human-caused emissions of carbon dioxide and other heat-trapping gases are making a discernible contribution to global warming.1  Despite promises by the president that “my Administration’s climate change policy will be science-based,”2 the past several years have seen widespread political interference in the work of federal climate scientists, edits to official scientific documents and a general attempt to foster uncertainty about robust scientific conclusions.

After coming to office, the administration asked the National Academy of Sciences (NAS) to review the findings of the Intergovernmental Panel on Climate Change (IPCC) and provide further assessment of climate science’s “certainties and uncertainties.”3  In 2001 the NAS panel rendered a strong opinion affirming the conclusions of the IPCC and stating that “Greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise.”4 

Also in 2001, President George W. Bush established the U.S. Climate Change Research Initiative (CCRI). One of the initiative’s two main priorities was to study “areas of uncertainty” in global climate change science.5 

In May 2002, President Bush expressed disdain for a State Department report6 to the United Nations that pointed to a clear human role in the accumulation of heat-trapping gases and detailed the likely negative consequences of climate change; the president called it “a report put out by the bureaucracy.”7  In September 2002, the administration removed a section on climate change from the Environmental Protection Agency’s (EPA) annual air pollution report,8 even though the climate issue had been discussed in the report in each of the preceding five years.

The American Geophysical Union (AGU), the world’s largest organization of earth scientists, released a strong statement in 2003 describing human-caused disruptions of Earth’s climate.9  “Human activities are increasingly altering the Earth's climate,” the AGU statement declared. Yet Bush administration spokespersons continued to contend that uncertainties in climate science were too great to warrant mandatory action to slow emissions.10 

Scientists were also largely excluded from internal policy discussions relating to climate change.  “This administration seems to want to make environmental policy at the White House,” an EPA scientist said. “I suppose that is their right. But one has to ask: on the basis of what information is this policy being promulgated? What views are being represented? Who is involved in the decision making? What kind of credible expertise is being brought to bear?”11  The Bush administration often “does not even invite the EPA into the discussion” on climate change issues, the scientist said.

Dr. Rosina Bierbaum, a Clinton administration appointee to the Office of Science and Technology Policy (OSTP) who also served during the first year of the Bush administration, also said that science was kept out of the process of policymaking on the topic of climate change. From the start of the Bush years, Bierbaum said, “The scientists [who] knew the most about climate change at OSTP were not allowed to participate in deliberations on the issue within the White House inner circle.”12 

Through such consistent tactics and a focus on uncertainty, the Bush administration has avoided fashioning any policies that would significantly reduce the threat implied by those findings.

The discussion may have changed with the February 2007 release of a report by the Intergovernmental Panel on Climate Change (IPCC), made up of hundreds of scientists from 113 countries, which declared that “human-generated greenhouse gases account for most of the global rise in temperatures over the past half-century.” The New York Times quoted Achim Steiner, executive director of the United Nations Environment Program, as saying “Feb. 2 [2007] will be remembered as the date when uncertainty was removed as to whether humans had anything to do with climate change on this planet.”13 

The 2007 report Atmosphere of Pressure, by the Union of Concerned Scientists and the Government Accountability Project, extensively documents Bush administration efforts to manipulate the work of federal climate scientists and exercise strict control over which scientists are allowed to talk to the media and which scientific results are communicated to the public.14 

1. This page contains material excerpted from the 2004 UCS Report, Scientific Integrity in Policymaking.

2. White House, President’s Statement on Climate Change (July 13, 2001).

3. National Academy of Sciences, Commission on Geosciences, Environment and Resources, Climate Change Science: An Analysis of Some Key Questions, 2001.

4. Ibid.

5. U.S. Climate Change Science Program.  2003. The Climate Change Research Initiative.  Washington, DC. Accessed October 25, 2006.

6. US Climate Action Report, Department of State, May 2002.

7. K.Q. Seelye, “President Distances Himself from Global Warming Report,” New York Times, June 5, 2002.

8. Past EPA Air Trends Reports can be found at; the 2001 report is the first Summary Report that doesn’t discuss climate change.

9. American Geophysical Union, Human Impacts on Climate, December 2003.  Accessed March 13, 2007.

10. P. Dobriansky, “Only New Technology Can Halt Climate Change,” Financial Times, December 1, 2003.

11. Author interview with EPA scientist, name withheld on request, January 2004.

12. As quoted in N. Thompson, “Science friction: The growing—and dangerous—divide between scientists and the GOP,” Washington Monthly, July/August 2003.  Accessed March 13, 2007.

13. Rosenthal, E. and Revkin, A.C., Science Panel Calls Global Warming “Unequivocal,” New York Times, February 2, 2007.  Accessed March 13, 2007.

14. Union of Concerned Scientists and Government Accountability Project.  2007. Atmosphere of Pressure.

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