NCPA - National Center for Policy Analysis


October 2, 2008

In May 2007, the U.S. Supreme Court decided that greenhouse gases met the definition of an air pollutant in the Clean Air Act.  The Environmental Protection Agency (EPA) responded in 2008 by issuing an Advance Notice of Proposed Rulemaking (ANPR) that explains how the Clean Air Act applies to regulating emissions of greenhouse gases thought to contribute to global warming.  The notice will likely be followed by regulations to reduce emissions.  Unfortunately, such regulations would significantly increase energy prices, but would not affect the global level of greenhouse gases, says Amanda Berg, legislative assistant for the National Center for Policy Analysis.

Human activities are only responsible for about one-quarter of one percent of the total greenhouse effect, which is the moderation of the Earth's temperature due to the absorption of the sun's radiation by atmospheric gases, says Berg:

  • Human activities contribute 0.28 percent to the greenhouse effect.
  • Natural greenhouse gas emissions -- including ocean biologic activity and decaying plants -- contribute 4.72 percent.
  • Water vapor accounts for 95 percent of the greenhouse effect.

Attempting to reduce such a small fraction of the factors that contribute to the overall greenhouse effect will be extremely costly and ineffective.

Furthermore, the proposed EPA rule would result in an unprecedented expansion of the EPA's power, giving them the authority to regulate nearly every sector of the economy and personal decisions about housing and transportation.  These sweeping regulations would cause energy prices to rise, but would be futile because of their negligible impact on the overall concentration of greenhouse gases, concludes Berg.

Source: Amanda Berg, "Regulating Global Warming: Expanding the Authority of the Environmental Protection Agency," National Center for Policy Analysis, Brief Analysis, No. 164, October 2, 2008.

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