"Global warming is a national and international crisis. And even if the federal government won't do anything, many states will," said California Atty. Gen. Bill Lockyer, who filed one of several lawsuits challenging the Bush administration's decision not to act on greenhouse gases.
The legality of California's new vehicle emission standards remains in doubt. They must be approved by the EPA. But the agency has yet to do so, mostly because of its view that carbon dioxide and other greenhouse gases are not air pollutants under the Clean Air Act.
The automakers have sued to block California's rules, citing the EPA's stand.
Humans and animals exhale carbon dioxide, and plants absorb it. It is also emitted from tailpipes and smokestacks when fossil fuels are burned. Once in the atmosphere, carbon dioxide absorbs the sun's radiation and traps heat in the atmosphere. This is known as the greenhouse effect.
As these greenhouse gases -- including methane, nitrous oxide and fluorocarbons -- have become more concentrated in the atmosphere, temperatures have increased slowly but steadily. Though some scientists and politicians once dismissed this link, most now acknowledge it.
Bush administration lawyers do not discount the importance of global warming, but they argue it is not covered by the Clean Air Act. That measure, they say, targets pollutants, such as ozone, that are dangerous to breathe -- not ones that occur in nature and are essentially harmless to breathe, such as carbon dioxide.
Disagreeing, the states' lawyers point to the language of the law. It says an air pollutant is "any physical, chemical (or) biological
In their brief to the court, they point out, "Motor vehicles emit the physical and chemical matter carbon dioxide, methane, nitrous oxide and hydro-fluorocarbons into the ambient air." Motor vehicles are the source of about 25% of the nation's greenhouse gas emissions.
It says 'shall'
Another provision appears to require regulation of such gases. It says the EPA "shall" regulate any pollutant from cars or trucks "which may reasonably be anticipated to endanger public health or welfare." The law defines the public's welfare to include effects on "climate" and "weather."
The state lawyers argue that because it is now apparent that greenhouse gases are endangering the public welfare, the EPA must regulate them.
