Today, EPA gave notice that it intends to regulate greenhouse gases under the federal Clean Air Act. Technically, the notice is a proposed finding that greenhouse gases endanger public health. When it becomes final after EPA has had a chance to consider public comments, this finding will trigger other regulatory requirements that will move the U.S. in the right direction.
EPA's announcement is an important landmark, because it is an unambiguous acknowledgment -- finally -- that the federal government must play a role in curbing global warming. Perhaps more important, it will add critical momentum to congressional efforts to pass climate change legislation, because it effectively eliminates any hope that industry had of avoiding regulation of carbon emissions altogether. Opponents now know that if they delay or defeat climate change legislation, they'll eventually face regulation from EPA. That ought to focus the debate.
Some background: Section 202 of the Clean Air Act requires EPA to regulate “any air pollutant from any class or classes of new motor vehicles or new motor vehicle engines, which in its judgment cause, or contribute to, air pollution which may reasonably be anticipated to endanger public health or welfare.” In other words, to be regulated, a substance emitted by vehicles must: (1) be an “air pollutant,” and (2) “endanger” health or welfare. The Bush EPA took the position that greenhouse gases aren’t technically “air pollutants” and that even if they were, regulation under the Clean Air Act wouldn’t be good policy.
The Bush EPA was slapped down by the Supreme Court in Massachusetts v. EPA. The historic opinion was written by Justice Stevens, who wrote that greenhouse gases were clearly covered by the statutory definition of air pollutants. Justice Stevens also said that EPA had no business considering extraneous policy arguments rather than implementing the statute passed by Congress. Thus, the Court made it clear that the agency’s only role is to determine the existence of “endangerment.” The agency was directed to do so in no uncertain terms.
The Bush EPA was no more interested in carrying out mandates from the Supreme Court than mandates from Congress. It simply stalled, attempting to run out the clock until Bush left office. When Obama came to Washington, it was plain that the agency would have to rule on this issue. There was very little doubt about how the agency would in fact rule. Not only is the science clear, but the Supreme Court itself had identified serious harm from climate change such as rising sea levels -- an issue that the Court had to address in order to find that the plaintiffs in the case were actually injured and did have standing.
Today’s agency action dutifully carries out the Supreme Court’s mandate. Industry and conservative advocates will undoubtedly criticize the agency on policy grounds. But the agency really had no choice under the law: it had to base its decision solely on science, not policy. Few reputable scientists would dissent from EPA’s conclusion that the “effects of climate change observed to date and projected to occur in the future include, but are not limited to, more frequent and intense heat waves, more severe wildfires, degraded air quality, more heavy downpours and flooding, increased drought, greater sea level rise, more intense storms, harm to water resources, harm to agriculture, and harm to wildlife and ecosystems.” Nor could any expert doubt that emissions from motor vehicles “cause or contribute to” climate change.
Under section 202, the next step after the endangerment finding becomes final will be a new regulatory effort to set the applicable standards. More significantly, EPA will also be faced with the question of whether to classify greenhouse gases as “criterion pollutants.” The standard for making this determination is very similar to the endangerment standard under section 209. Classifying a substance as a criterion pollutant triggers a different set of requirements under the Clean Air Act that apply to power plants, factories, and other stationary pollution sources. It is very difficult to see how EPA can avoid making that additional determination and bringing the full weight of the Clean Air Act to bear on mitigating greenhouse gases.
Implementing regulations for cars and trucks will be a routine (though not simple) regulatory task. Using the Clean Air Act to regulate greenhouse gases from factories and power plants is trickier, because the relevant provisions of the Clean Air Act are best designed for dealing with local forms of pollutions such as particulates and carbon monoxide. But the EPA has considerable ingenuity at adapting the statute to unforeseen issues.
Regulating greenhouse gases under the Clean Air Act is not ideal. It would be better to have new federal legislation that addresses climate change explicitly. But, even with the prod of today’s EPA action, it may be a struggle to find the votes needed to pass new legislation. It is reassuring to have the Clean Air Act as a fallback if new legislation fails.