Columbia subject headings:
Air quality management--United States.
Carbon dioxide--Environmental aspects--United States.
Greenhouse gases--Environmental aspects--United States.
Greenhouse gases--Environmental aspects.
Harvard subject headings:
Air quality management--United States
Carbon dioxide--Environmental aspects--United States.
Climatic changes
Environmental policy--United States
Global warming.
Greenhouse effect, Atmospheric.
Greenhouse gases--Environmental aspects--United States
Princeton subject headings: