Scientists Voice Support For Curbing Carbon Dioxide

On Aug. 31, 18 prominent climate-change researchers filed a brief with the Supreme Court expressing their support for regulating CO₂ emissions from motor vehicles in a global warming case that is before the high court. Among the signers are F. Sherwood Rowland and Mario J. Molina, who shared the 1995 Nobel Prize in Chemistry for their work in atmospheric chemistry.

The Supreme Court case—Commonwealth of Massachusetts v. U.S. Environmental Protection Agency—has a long history. In 1999, various environmental groups petitioned EPA, asking it to set motor vehicle emission standards for greenhouse gases. EPA denied the petition, saying that the Clean Air Act provides no authority to regulate CO₂ and that , even if the agency had authority, it preferred voluntary programs and further study.

In 2003, Massachusetts, 11 other states, and environmental groups challenged EPA's ruling in the U.S. Court of Appeals for the District of Columbia. The court upheld EPA's decision last year.

In March of this year, Massachusetts and 28 other parties requested Supreme Court review of the case, and in June, the court agreed to hear it (C&EN, July 3, page 7).

In their brief, the scientists say they originally believed they would not see strong signs of human-induced climate change during their lifetimes. But by the beginning of this decade, "we observed that global temperatures are rising, plant and animal ranges are shifting, glaciers are in retreat globally, and Arctic sea ice is retreating." In addition, "sea levels are rising, and the oceans are becoming more acidic," they write. "We know these changes are just a small increment of climate change yet to come if human societies do not curb emissions of greenhouse gases."

The evidence of the changes is so compelling, the researchers write in their brief, that a consensus has crystallized within the scientific community: Global warming is happening, and it is virtually certain human activities are causing it. In denying the petition to regulate CO₂ emissions from mobile sources, the scientists write, EPA misrepresented the findings contained in a 2001 National Research Council report on climate change by selectively quoting statements about uncertainty while ignoring statements of certainty.

The high court will hear oral arguments in the case in December.