A Free-Market Energy Blog

Remove the Golden Egg (CO2) from EPA’s GHG Basket

By Chip Knappenberger -- June 16, 2009

In its Proposed Endangerment and Cause or Contribute Findings for Greenhouse Gases Under Sections 202(a) of the Clean Air Act , the Environmental Protection Agency (EPA) places six greenhouse gases into one basket. All are treated as equal, primary culprits in the anthropogenic enhancement of the earth’s greenhouse effect, and thus the EPA proposes to find that they “endanger the public health and welfare of current and future generations.” The six are carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride.

But for many reasons, one of these gases is not like the others and should be considered separately. That gas is carbon dioxide.

The Green Greenhouse Gas

Carbon dioxide (CO2) is essential to life on earth as we know it. It is a necessary ingredient in the photosynthetic recipe that produces the oxygen that we breathe as well as the carbohydrates that we eat. The more CO2 in the atmosphere, the better plants grow. And better-growing plants are, obviously, a boon for the planet’s animal life (including humans).

Interestingly, not only does carbon dioxide make plants grow better and be more productive, but it makes them more resistant to other environmental stressors. More CO2 reduces the negative impacts on plants from air pollution including low-level ozone concentrations (EPA sees low-level ozone concentrations rising under global warming). More CO2 improves the water-use efficiency of plants, that is, they require less water to go about their business (EPA sees global warming as placing a growing burden on our water supply). More CO2 also enables plants to survive (or, in some cases, even thrive in) higher temperatures (the EPA sees future temperatures rising).

(For a long, long list of scientific references in support of my claims concerning CO2 and plants, and for other positive impacts I failed to mention, please visit the CO2 Science webpage – far and away the web’s most thorough documentation of the interaction between carbon dioxide and the earth’s plant species)

So, not only does CO2 directly improve the productivity of the earth’s plant life, but it also helps mitigate many of the impacts of environmental changes identified by the EPA—and both of these responses lead to positive downstream impacts on the rest of the planet. So regulations aimed at reducing atmospheric CO2 levels also are aimed at reducing these benefits.


These effects are unique to carbon dioxide among the EPA’s collection of GHGs. Thus CO2 should not be grouped together with the other five GHGs, and instead it should be judged independently as to its impacts on public health and welfare. Atmospheric CO2 increases have overwhelmingly positive impacts on the earth’s ecology which lead to similarly positive impacts on public health (e.g., better producing food crops) and welfare (which the Clean Air Act defines as including “effects on soils, water, crops, vegetation, man-made materials, animals, wildlife, weather, visibility, and climate…”—of which better-growing plants positively impacts many of the listed items).

So the far-reaching benefits from increasing atmospheric CO2 would have to be weighed against any negative consequences—i.e., oceanic acidification (see here for why this concern is on wobbly legs), and presumably those arising from its role in enhancing the global greenhouse effect and the resulting impacts on the climate—to which the EPA has built a rather long list (even though scientific support for many of the items on the list is far less than EPA establishes, see here for example).

But let’s look a little closer at CO2’s role in climate change and climate change impacts.First, consider that CO2 makes up less than one-half of the total warming pressure (positive climate forcing) attributed to anthropogenic activities. According the IPCC’s numbers (which are relied upon by the EPA) the total positive anthropogenic climate forcing increase (which includes not only GHGs, but also the impacts from black carbon aerosols, tropospheric ozone, and stratospheric water vapor) since pre-industrial times totals about 3.16 W/m2, of which CO2 makes up 1.66W/m2, or 53%.

But, new research (highlighted in the Proposed Endangerment) by Ramanathan and Carmichael concluded that the warming impact of black carbon aerosols was underestimated by the IPCC. Incorporating the results of Ramanathan and Carmichael, the total positive forcing from anthropogenic activities becomes about 3.86 W/m2, which means CO2 only makes up 43% of the total. By extension, therefore, CO2 is only responsible for a modest 43% of the total climate change.

This has direct consequences to EPA’s Proposed Endangerment, for in it the EPA admits that:

The Administrator also acknowledges that warming temperatures may bring about some health benefits. Both extremely cold days and extremely hot days are dangerous to human health. But at least in the short run, modest temperature increases may produce health benefits in the U.S. (and elsewhere).


The Administrator acknowledges that as for human health, so too for welfare: moderate temperature increases may have some benefits, particularly for agriculture and forestry over the short term…

And “modest” or “moderate” temperature increases are all the CO2 alone has to offer!

Of note is that the EPA keeps repeating “in the short-term” not to refer to the benefits from modest warming, but to indicate that the EPA doesn’t think that the temperature increase will be modest for very long—but if they only considered CO2, it probably would be.


According to the Proposed Endangerment, the EPA Administrator has to find that an air pollutant “may reasonably be anticipated to endanger public health or welfare” in order to take regulatory action. However, making this case for CO2 presents the EPA with a far greater task than is the case now when CO2 is thrown into the same basket as methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride.

To make a fair and scientifically just finding, the EPA must consider its Golden Egg on its own merits. If it were forced to do so, the EPA would be faced with a situation in which the benefits of enhanced atmospheric CO2 concentrations quite possibly overcome any negative conseqences.


IPCC, 2007. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Solomon, S., et al. (eds), Cambridge University Press, Cambridge, U.K., 996pp.

Ramanathan, V., and G. Carmichael, 2008. Global and regional climate changes due to black carbon. Nature Geosciences, 1, 221-227.


  1. Andrew  

    One wonders why the EPA doesn’t have plans to regulate soot or land use or anything like that. Oh, right, climate/health impacts don’t matter. Science doesn’t matter. It is all about control.


  2. Allen  

    Interesting comment on the master resource post….does EPA have any plans to regulate soot? Yes they do and they have. In fact, most of the benefits derived from establishing the national ambient air quality standards for PM2.5, O3, Pb, NO2, SO2, etc. are derived from the mortality and morbidity risk reduction benefits associated with reducing particulate concentrations directly, or via control of precursor emissions of ozone, lead, nitrogen dioxide and sulfur dioxide.

    The master resource post does address the void in EPA’s proposed finding with respect to the near term effects consequences relative to the more distant and uncertain effects. However, the 43% is still a large number. But, the percentage pertinent for the endangerment finding is much lower. Why? The USA is just a part of the world’s current and future CO2 loadings.,,not as big as China last year. Moreover, the effectiveness of any USA GHG reduction strategy is dependent on what the rest of the world does in the interim. Do we find as we have with the primary smelting, textile, steel industry, and other formerly dominant domestic industries that stringent regulations and costly emission reduction requirements in the USA offer opportunities across our borders and offshore? Yes!! What EPA fails to address in the proposed endangerment finding is the marginal effect of domestic GHG emissions changes on radiative forcing. To do that EPA must address what other countries are doing or may do in the interim as well as the deficiencies of macro meterological and emissions inventory projection models in predicting impacts on narrow geographic areas where the alledged significant endangerment may occur.


  3. Fred H. Haynie  

    To all concerned,

    One reason I retired early from research at EPA years ago was good
    science was beginning to be sidetracked for political purposes. In this
    case EPA has been completely derailed. I have spent the last four years
    of my retirement studying all the data I could find to get to the truth about climate change. I just finished a presentation that shows ample evidence that anthropogenic emissions of carbon dioxide do not cause global warming. Carbon dioxide has been falsely convicted on circumstantial evidence by a politically selected jury. A just retrial could overturn this conviction before we punish ourselves by trying to control emissions that will have no effect on climate change. You can view the presentation and be your on judge and jury at http://www.kidswincom.net/climatechangepdf

    .pdf Sincerely,

    Fred H. Haynie
    Retired Environmental Scientist


  4. Chass  

    Fred –

    Can you check your link? I couldnt’t get a copy of your climatechange.pdf to download.



  5. Fred H. Haynie  

    Try this http:\www.kidswincom.netclimate.pdf



  6. Joe LaVigna  

    Do you have or use a biography summary that you care to share so that I can send it along with copies of your very fine pdf report?


  7. Fred H. Haynie  

    Basically, I have a master’s degree in chemical engineering from Auburn, masters in metallurgical engineering from Ohio State, addition graduate work at Georgia Tech and the University of Pennsylvinia, and a certificate from the Environmental Management Institute at USC. At EPA I served in several organizations as we seemed to be constantly being reorganized (Economics Effects Research Division, Ecology Division, Environmental Sciences Research Laboratory). I worked with economist, engineers, plant pathologists, statisticians, meteoroligist, and atmospheric chemists. I was an active member of AIChE, ASTM, and NACE. Google “Fred H. Haynie” to view examples of some of my publications. As an aside, I spent seven years on active duty as a naval aviator and remained in the reserves and retired as a Captain. One reserve job was in a Systems Analysis Division studying command and control.


  8. Roger Pielke Jr. Challenges Joe Romm: Looking for Intellectual Improvement — MasterResource  

    […] etc.) that should be recognized as such. There are ecological and economic positives from the green greenhouse gas that should be factored into the equation–a happy fact given that politics cannot solve the […]


  9. More Deceit from Climate Progress, Center for American Progress (Is Joe Romm shooting himself in the foot?) — MasterResource  

    […] etc.) that should be recognized as such. There are ecological and economic positives from the green greenhouse gas that should be factored into the equation–a happy fact given that politics cannot solve the […]


Leave a Reply