In an op-ed piece, Joseph R. Reisert wrote:
the states insist that the Clean Air Act, which was enacted in its current form in 1990, already requires the EPA to address global warming, because it states that the EPA's top administrator "shall" impose limits on the amount of any "air pollutant" new cars may emit whenever that pollutant will "in his judgment cause, or contribute to air pollution which may reasonably be anticipated to endanger public health or welfare." In their view, carbon dioxide must be regulated as an air pollutant because it contributes to global warming, which will, in their view, inevitably endanger the public health and welfare.
One can see a Philips "claim term interpretation" issue in the way "air pollutant" is to be construed. Carbon dioxide is a natural product in the oxidation of carbon-containing molecules, and is made both by cars and human beings. Chemically speaking, it is fairly inert, unlike certain oxides of sulfur and nitrogen, the real targets of pollution control.
Before jumping to any conclusions about how certain justices construe terms, environmental activists and non-activists might wish to review Justice Scalia's decisions both in Merck v. Integra and (especially) the earlier Medtronic case in the realm of patent law.