Day Two: Reaction to the EPA

December 8, 2009

(Updated with comments from Dr. Gidon Eshel, physics professor, Bard College)

On the first day of the United Nations Conference on Climate Change in Copenhagen, the U.S. Environmental Protection Agency cleared the way for regulation of greenhouse gases without new laws passed by Congress, reflecting President Barack Obama’s commitment to act on climate change.

The EPA ruling that greenhouse gases endanger human health was widely expected, but for the record, asked our panel of experts on climate change what they thought of the decision.

Watch this space throughout the conference, which runs to Dec. 18. We’ll be asking some of the world’s foremost thinkers timely questions about breaking news and overarching themes about fighting global warming. We hope you will join the discussion.

Today’s question: What does the EPA announcement mean for the climate debate and what are the potential impacts on businesses?

ray2 Dr. Raymond Pierrehumbert, Louis Block Professor in geophysical sciences at the University of Chicago:

The anticipated EPA finding that CO2 is a pollutant is entirely appropriate and indeed long overdue.  Some will say that CO2 can’t be a pollutant because it isn’t directly toxic and occurs naturally in the environment.

That is such an overly narrow view of the notion of “pollutant” that it would actually exclude most things that EPA routinely regulates.

For example, Mercury occurs to some extent naturally in the environment; so do heavy metals such as Chromium, which in fact are necessary micronutrients in small doses.

Nonetheless, these need to be regulated because they cause great harm when emitted at the rates that industry is capable of.  In the case of Mercury, the EPA is already dealing with the fact that much of the emission can cross international borders, so CO2 is not different in that way either.

A pollutant is any thing that is affected by human-controlled emissions, which can cause harm in sufficient quantities. CO2 solidly fits that definition. The finding of harm would be justified even just by the anticipated effects of global warming on heat waves alone.

It is often said that EPA regulation is not the most natural way to control carbon emissions, but I’m not even sure I agree with that.

In some sectors, notably power plants, taking CO2 emissions into account  fits very naturally into the permitting process.

To be sure, some things such as carbon taxes are outside the purview of the EPA, but to the extent that such things come to pass they would complement direct regulatory action by EPA.

The higher the price on carbon, the less economic coal-fired power will be without sequestration, and that will naturally reduce the number of cases in which EPA needs to consider CO2 emissions as part of the permitting process. ”



Dr. Gidon Eshel, physics professor at Bard College:

CO2 is a tricky one.

It is certainly not toxic or harmful to people at the minor concentrations we are talking about in any foreseeable atmospheric scenario, so in that sense it is not a pollutant.

The reason I think it DOES make sense to classify it as a pollutant (thereby broadening the definition of a pollutant) is that it is highly unlikely that rising levels of atmospheric GHGs are not indirectly harmful to the biosphere and humans therein.

The two most obvious risks associated with rising CO2 are (1) accompanying rising global mean temperatures, and (2) the effects of ocean acidification due to invasion of atmospheric CO2 into ocean waters on already stressed to the brink ocean life.

Regarding point 1: There is a strong, sound and well-developed theory connecting GHG concentrations and global mean temperatures, atmospheric radiation transfer theory, the theoretical body of knowledge addressing interactions of EM radiation and matter. So we have a solid a priori theoretical foundation for expecting global mean temperatures to rise in response to thickening (wrt GHG) atmosphere. We have been experiencing rising GHG concentrations, and, lo and behold, we have also been experiencing rising global mean temperatures.

Could the two possibly be related, by appeal to radiation transfer?! Outlandish though this may sound, the EPA’s move indicate they decided to wait no longer for Senator Inhofe’s green light, and have decided, all on their own, that yes, it is possible.

For the climate debate, this most likely means little. Those who wish to emphasize the uncertainty, will continue to  do so. It  is in some sense prudent: no, we are not sure thickening atmosphere caused the observed warming. At least not flat 100 percent sure.

The case is not close. But any closed case is not a scientific problem, nothing in science is ever 100 percent settled, there are more or less likely scenarios, more or less conjectural routes to getting from observations to an

To my somewhat subjective mind, the least conjectural, the least fanciful, way of explaining the dramatic recent temperature rise is  by invoking the contemporaneous rise  in atmospheric GHG concentrations. It is false, however, and unhelpful, to claim the case is settled and there are no lingering doubts.

I will leave the effect on business to those who know business.



Kim Carstensen, leader of the World Wildlife Fund Global Climate Initiative:

Just hours after the official launch of COP15, the negotiations were injected with an added boost of optimism upon news that the United States was moving closer toward eventual regulation of greenhouse gases by the U.S. Environmental Protection Agency (EPA).

Here in Copenhagen, the announcement sent a clear, unmistakable message that President Obama is serious about addressing climate change and, as such, it was taken as very good news by many of the negotiating parties.

Sealing a global deal, though, will require confidence by the international community that the U.S. will be able to follow through on its commitments.

And to secure that we still need a comprehensive U.S. climate change bill, which is still clearly the best way to provide the long-term certainty we need.

So when President Obama arrives here next week, the world will be looking for him to announce that climate change will be his next legislative priority.



Knut Alfsen, Head Research Director, Center for International Climate and Environmental Research, Oslo (CICERO):

The endangerment decision by EPA implies that, according to EPA, CO2 emissions from the transport sector is damaging to human health and therefore to be regulated under the Clean Air Act unless a climate act is passed covering the same emissions.

Nobody really want EPA to regulate CO2 emissions. This would be very cumbersome, time-consuming and costly as the regulation would have to be sector by sector and perhaps even firm by firm.

Thus, the decision by EPA increases the chances for a climate law to pass the Senate.


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