Does the US EPA have the authority to regulate CO2 and other greenhouse gases? Are carbon dioxide, methane, nitrous oxide and hydrofluorocarbons – air pollutants? Is EPA not acting enough to regulate these gases under the Clean Air Act (EPA.gov)? What is the responsibility of the government in these matters?

These and many other questions are being debated in this historic court case (SFgate.com).

The EPA is not ready to regulate CO2 on the basis that it “even if the agency had the authority to regulate greenhouse gases, it wouldn’t because of scientific uncertainty around global warming and because limiting U.S. emissions could hurt the president’s ability to persuade other countries to reduce their greenhouse gas output.”

Lets look at the scientific argument.

According to the survey by Naomi Oreskes (sciencemag.org), which was cited by Gore in ‘An Incovenient Truth’, there is a concensus among scientific community on human-induced global warming.

This analysis shows that scientists publishing in the peer-reviewed literature agree with IPCC, the National Academy of Sciences, and the public statements of their professional societies. Politicians, economists, journalists, and others may have the impression of confusion, disagreement, or discord among climate scientists, but that impression is incorrect.

The scientific consensus might, of course, be wrong. If the history of science teaches anything, it is humility, and no one can be faulted for failing to act on what is not known. But our grandchildren will surely blame us if they find that we understood the reality of anthropogenic climate change and failed to do anything about it.

The EPA’s scientific argument is totally wrong. Frankly, I do not have the scientific background to understand all the science behind this issue. However, that is the case for many scientific ideas that I believe in.

For example,

• The earth is round
• The Solar System and the Universe
• Health problems and medical solutions
• Atoms and molecules
• The nervous system in human beings
• How does the aeroplane fly?

As lay people we are used to understanding scientific conclusions without understanding the science.

The second part is the US vc China debate.

Justice Samuel Alito suggested EPA was right to propose that United States wait to cut emissions until other countries agreed to the same.

“What is wrong with their view that for the United States to proceed unilaterally would make things worse?” Alito said.

This is factually wrong. First, as I explained before (India and Emissions) China, India or any of the other emerging econmies cannot be blamed for increasing their emissions. Second, the US is not unilaterally in this.

As of Sep 2006, some 163 countries (wikipedia.com) have signed and ratified the Kyoto Protocol (wikipedia.com). Australia and US (the red countries in the figure on the left) are the only countries which have signed but are not intending to ratify. Croatia and Kazakhstan (light green in the accompanying figure) have signed but have not yet ratified.

So, the US is not alone in this. The UK and the EU have been working on many laws mandating greenhouse gases, e-waste (europa.eu) etc. and the EU has a carbon trading scheme underway too.

In fact, the EU is going to propose mandatary cuts next year (Yahoo! News).

European Commission plans to propose new mandatory targets for EU nations to cut greenhouse gas emissions in an effort to battle climate change, its president, Jose Manuel Barroso, said on Thursday.

European Union member states already face targets up to 2012 to cut emissions under the international Kyoto Protocol on global warming, while its industry faces caps on carbon dioxide (CO2) under the bloc’s carbon trading scheme.

It will be interesting to see how this court battle will continue. But it will depend on convincing people like Justice Antonin Scalia.

“Is it an air pollutant that endangers health? I think it has to endanger health by reason of polluting the air, and this does not endanger health by reason of polluting the air at all.”

Justice Antonin Scalia