Global-warming objectivity is debating “why,” not “if”

A classic example of so-called “objectivity” functioning as a mask for ideological obfuscation is the “debate” over global warming. The form over which the corporate mass media presents the issue is as if there is a question of whether Earth’s climate is changing, presenting humanity with grave challenges.

A foolish “debate,” as climate scientists are nearly unanimous in the reality of global warming, and the world’s temperatures are indisputably rising as gases that create a greenhouse effect continue to be pumped into the atmosphere. More than three decades have passed since the last year in which global temperatures were below average (1976) and each of the past twelve years ranks among the fourteen hottest years ever recorded. Droughts, severe heat waves and devastating storms are becoming more common, and Arctic Ocean ice coverage again reached an all-time low last summer.

There is no other explanation for this accelerating phenomenon other than increases in atmospheric gases that trap heat. And there is no other explanation for the sources of those accumulations other than human industrial and agricultural activities. Because oil and gas production and usage are the largest single source of human-caused greenhouse gases, companies involved in that industry have incentives to deny global warming, and the money to propagate their desired message.

Energy companies, automobile manufacturers and their lobbyists fund a variety of “research institutes” that pump out reports with pre-determined conclusions. At least two of their denialist institutes started life as shills for the tobacco industry, pumping out reports denying links between smoking and health problems. Excepting those news outlets with obvious Right-wing biases, what is often at work here is an unthinking application of the concept of “neutrality,” a cherished ideal in the mass media of many countries. The concept of media “neutrality” is easily exploited by lavishly funded corporate fronts that pump out reports and provide spokespeople.

“Neutrality,” in any rational sense, shouldn’t mean a “balance” between reality and self-serving non-reality. A legitimate debate on global warming would center on which human activities have significant responsibility and at what point greenhouse gas emissions reach a tipping point where climate change would be beyond human ability to counter effectively.

The industry-or-livestock debate

Environmentalists and others concerned about the health of the world are in agreement that greenhouse gases are putting Earth at serious risk. The debate here concerns whether industrial activity or animal agriculture is the main culprit. Determining which is the bigger contributor to global warming partly requires determining what gases contribute most. This, too, as a byproduct of the industry/livestock debate, is itself a matter of debate.

Some groups focus on the level of carbon dioxide in the atmosphere because there is far more of it than other greenhouse gases. For example, 350.org derives it name from a consensus that humanity must reduce the level of carbon dioxide gases in the atmosphere to 350 parts per million (ppm) from the current 392 ppm but still well above the pre-industrial level of 275 ppm. Similarly, the Oxford e-Research Centre’s Trillionth Tonne web site says that when humanity has pumped 1 trillion tons of carbon (cumulatively, for all history) into the atmosphere, runaway climate change will ensue; the web site’s calculator estimates that more than 566 billion tons have been emitted.

Both of these groups acknowledge the other greenhouse gases, but see carbon dioxide — and, thus, industrial activity — as the crucial factor. The Trillionth Tonne web site says:

“Other greenhouse gases also cause warming, while other forms of pollution cause cooling. So far, these effects very approximately cancel out, but this is unlikely to remain so. … Carbon dioxide emissions are the single most important factor in the future and, under all current scenarios, the net effect of other emissions is to add to the warming caused by carbon dioxide. So to limit total global warming caused by human activity to less than 2 °C, we clearly have to limit the warming caused by carbon dioxide to less than 2 °C.”

A rise in global temperature of 2 degrees Celsius above the long-term median is a more common way of expressing the climatic tipping point.

Some organizations see contributions from industrial activity and animal agriculture. The Skeptical Science web site maintained by an Australian scientist, for example, says:

“While methane is a more potent greenhouse gas than CO2, there is over 200 times more CO2 in the atmosphere. E.g., CO2 levels are 380 ppm while methane levels are 1.75ppm. Hence the amount of warming methane contributes is calculated at 28% of the warming CO2 contributes. … This is not to say methane can be ignored — reducing methane levels is definitely a goal to pursue.”

And then there are vegan and vegetarian activists who say that it is animal agriculture that is mostly responsible for greenhouse gases, and that changes in diet from meat consumption would mitigate the threat. The non-profit agency EarthSave, for example, says that focusing on carbon dioxide levels is a mistake:

“Domestic legislative efforts concentrate on raising fuel economy standards, capping CO2 emissions from power plants, and investing in alternative energy sources. … This is a serious miscalculation. … It’s true that human activity produces vastly more CO2 than all other greenhouse gases put together. However, this does not mean it is responsible for most of the earth’s warming. Many other greenhouse gases trap heat far more powerfully than CO2, some of them tens of thousands of times more powerfully. When taking into account various gases’ global warming potential—defined as the amount of actual warming a gas will produce over the next one hundred years—it turns out that gases other than CO2 make up most of the global warming problem. … The surprising result is that sources of CO2 emissions are having roughly zero effect on global temperatures in the near-term!”

Sorting out competing theories

We have a wide range of opinions. To sort it out, it is necessary to find data and make some calculations. Activists who zero in on animal agriculture as the problem say methane and other gases are the problem, not carbon dioxide. They frequently cite a United Nations report issued in 2006, “Livestock’s Long Shadow: Environmental Issues and Options.” This is a detailed analysis that seeks to quantify the impact of animal agriculture on the environment and possible solutions to ameliorating the effects. The report says:

“The livestock sector is a major player [in climate change], responsible for 18 percent of greenhouse gas emissions measured in CO2 equivalent. This is a higher share than transport. … The sector emits 37 percent of [human-caused] methane. … It emits 65 percent of [human-caused] nitrous oxide, the great majority from manure.”

The methane and nitrous oxide that are pumped into the atmosphere matter, because those are much more effective greenhouse gases than carbon dioxide. Methane is 21 times more powerful than carbon dioxide and nitrous oxide is 310 times more powerful, according to internationally accepted standards. Those multiples are adjusted for the fact that CO2 is stable long term, while methane dissipates in an average of 12 years and nitrous oxide in 114 years. The United States Environmental Protection Agency publishes online the amount of the main greenhouse gases produced each year in the U.S., and the amounts generated by the various sources of those gases, calculated in millions of metric tons per carbon dioxide equivalent.

Using the agency’s 2010 figures to calculate the various amounts accountable to industrial activity and to animal agriculture (which are calculated in carbon dioxide equivalents, counting one methane ton as equivalent to 21 carbon dioxide tons and one nitrous oxide ton as 310 carbon dioxide tons), global-warming transmissions related to animal agriculture total three percent of industrial activity. (In making this calculation, I excluded emissions attributed to crop agriculture, natural causes and activities that contributed minuscule amounts.)

If these figures are in any way accurate, they demonstrate that industrial activity, in particular fossil fuel extraction and consumption, is overwhelmingly the main culprit. The Environmental Protection Agency report was prepared by professionals and scientists, not political-appointee higher-ups, so I see no reason to not regard its statistics as reliable. (Nor have I found any better or comparable data, which does not mean such data doesn’t exist.)

According to the report, fossil fuel consumption accounts for more than 90 percent of carbon dioxide emissions. Natural gas systems are the largest contributor to methane emissions, with livestock and landfill waste also significant. Agricultural soil management accounts for about two-thirds of nitrous oxide emissions (I did not count it for either side). Overall, the Environmental Protection Agency calculates that, from U.S. sources, the total contribution of methane and nitrous oxide to global warming are 17 percent that of carbon dioxide.

On the other hand, animal agriculture is not fully accounted for in the above report. Some portion of fossil fuel use is attributable to animal agriculture and the carbon imbalance caused by destruction of forest to clear land for livestock production is far more acute in other parts of the world, among other issues. Another section of the United Nations report quoted earlier says:

“Livestock also affect the carbon balance of land used for pasture or feed crops, and thus indirectly contribute to releasing large amounts of carbon into the atmosphere. The same happens when forest is cleared for pastures. … Some of the indirect effects are difficult to estimate, as land use related emissions vary widely, depending on biophysical factors as soil, vegetation and climate as well as on human practices.”

Those effects aren’t accounted for in the Environmental Protection Agency report. This is a debate that must continue; I am under no illusions that I have settled anything definitively. I should stress that the statistics are U.S. outputs for 2010, not global outputs, so the true planetary ratios likely vary. All sides quoted here agree that global warming is a dire problem that must be tackled now, as any reality-based analysis must do. Debating how to tackle global warming is immeasurably more productive than taking seriously tired arguments from self-interested deniers.

There is no single route to reversing global warming. Regardless of where the emphasis should be, Western consumerism is clearly unsustainable. The world’s people will not be using resources the way they now do in the not too distant future, whether changes are voluntary or imposed by the limits of nature. Endless growth on a finite planet can’t last forever.

4 comments on “Global-warming objectivity is debating “why,” not “if”

  1. Grace Weaver says:

    Your article purports to put forth the various sides to the debate, but in my view, by maintaining a posture of objectivity, your article reiterates (perhaps in greater detail) the same thing put forth in al gore’s film, “an inconvenient truth,” the mainstream (and even alternative press), 350.org and other environmental groups. these all emphasize CO2 as the main culprit in producing global warming. the new alternative scientific understanding puts methane and nitrous oxide gases as the main culprits and animal agriculture (meat, dairy, egg industries) as the primary producers of these greenhouse gases. by listing this last and almost towards the end of your piece, you give the appearance presenting all sides, but in reality emphasize the dominantly held position of co2 playing the major role. you thereby in my view insufficiently present these latest findings and therefore do not sufficiently offer your readers the option of a plant based diet and lifestyle as a most important way of ameliorating the problem of catastrophic climate change or “global warming.” By the way, the most “Inconvenient Truth” left out of Al Gore’s movie “the Inconvenient Truth” is that Al Gore owns 70,000 head of cattle and is therefore part of the animal agriculture industry, part of the major problem. i’m hoping the option of a plant based diet and lifestyle as a primary and immediate solution to global warming will appear in forthcoming articles. Thank you for opening up this topic for clarification and discussion.

    • Greetings, Grace, and thank you for your comments. Reversing global warming is going to require many changes in Western-style consumerism, and the large amount of land that is given over to livestock production/animal agriculture is surely a significant factor. The cutting down of forests, and especially tropical rain forests, to clear land for cattle alone is a serious contributor. (As to Al Gore, I’ve never seen An Inconvenient Truth nor have I read anything he has written on the subject; therefore, his hypocrisy is a non-issue for me.)

      Since publishing this post, I have had my attention drawn to a study that estimates 51 percent of global warming is due to animal agriculture, and that paper will be given due attention when I return to this topic. But note that the paper points to carbon dioxide, not methane, as a principal culprit. The debate over the sources of global warming, and even the debate over the specific global-warming effects of methane and nitrous oxide, are entirely legitimate. These are not settled questions, and you are right to raise them for further debate.

      Nonetheless, the amount of carbon dioxide, methane, nitrous oxide and other gases in Earth’s atmosphere is not debatable; these can be and are scientifically measured. As of February 2012, carbon dioxide concentration was 391 parts per million while methane concentration was 1.75 to 1.87 parts per million. The fact is there is not enough methane to make it more than a fraction of the global-warming causation of carbon dioxide. Claims that methane is the primary cause of global warming are not supported scientifically. Again, that does not mean that animal agriculture is not a significant factor nor does it mean the size of that factor is not part of a legitimate debate. We should be debating this topic, seriously, and we are not taking global warming seriously if we do not discuss the livestock and poultry industries.

      But I have to point that the activist organizations that assert carbon dioxide to be the primary greenhouse gas support their positions with scientific evidence. Evidence that can be rebutted with better evidence, if it exists. By contrast, those who assert methane to be the primary greenhouse gas often discuss the health benefits of vegetarianism or veganism but offer no scientific evidence to back their assertions about methane. I am in agreement with the statements concerning health and agree that such a diet would improve the public’s health and be gentler on the planet, but that does not constitute “proof” that methane outstrips carbon dioxide. If there is evidence to this, then I would certainly read it.

  2. Grace Weaver says:

    i refute your statement that:

    “the organizations that assert carbon dioxide to be the primary greenhouse gas support their positions with scientific evidence….By contrast, those who assert methane to be the primary greenhouse gas … offer no scientific evidence to back their assertions about methane.”

    This is simply not true.

    The article A New Global Warming Strategy: How Environmentalists are Overlooking Vegetarianism as the Most Effective Tool Against Climate Change in Our Lifetimes by Yale physicist, Noam Mohr, in the Earth Save International site quotes Dr James Hansen that CO2 is not the main culprit in global warming. Dr Hansen is Director of NASA’s Goddard Institute for Space Studies who has been called “a grandfather of the global warming theory.” In addition the Union of Concerned Scientists had the data reviewed by other climate experts, who affirmed Hansen’s conclusions. This article “A New Global Warming Strategy (in Earth Save Int’l) had 17 footnotes at the end listing sources and studies (for example: Hansen, James E. and Makiko Sato, “Trends of measured climate forcing agents”, Proceedings of the National Academy of Sciences, vol. 98, no. 26)

    In addition, most people are also not aware that the meat, dairy and egg industries use 1/3 of all petroleum. To quote Mark Bittman in his NY Times article: To put the energy-using demand of meat production into easy-to-understand terms, Gidon Eshel, a geophysicist at the Bard Center, and Pamela A. Martin, an assistant professor of geophysics at the University of Chicago, calculated that if Americans were to reduce meat consumption by just 20 percent it would be as if we all switched from a standard sedan — a Camry, say — to the ultra-efficient Prius. Similarly, a study last year by the National Institute of Livestock and Grassland Science in Japan estimated that 2.2 pounds of beef is responsible for the equivalent amount of carbon dioxide emitted by the average European car every 155 miles, and burns enough energy to light a 100-watt bulb for nearly 20 days.

    For more proof in the form of scientific studies, I suggest you and your readers look at

    the Earth Save Int’l Study ~
    by Yale physicist, Noam Mohr,
    a New Global Warming Strategy

    the U. of Chicago study:
    Diet, Energy, and Global Warming
    Gidon Eshel* and Pamela A. Martin
    Department of the Geophysical Sciences, University of Chicago,

    the Mark Bittman article in the NY Times ~
    Rethinking the Meat Guzzler

    and the United Nation’s Food and Agricultural report from the CCP (panel on climate change)
    Livestocks Long Shadow ~ Environment Issues and Options

    Thank you.

    • The larger point I have been making it this: Animal agriculture and industrial activity are both responsible for global warming. Those who say animal production have nothing to do with it are wrong, and those who say only animal production has something to do with it are wrong. The scientific debate is over what contribution various human activities make toward global warming, which in turn guides proper courses of action. You are arguing there is no debate, that one side is correct. But there is no scientific consensus, only competing various scientific theories. That is a normal and healthy development, and in fact is the way that science advances our understandings.

      You are arguing against a straw person since I have made no arguments that industrial activity is the sole or primary cause, but neither can I accept that it is irrelevant the massive use of fossil fuels in transportation, the outputs of factories and the widespread use of coal should be enough to put such an idea to rest.

      In looking over the Noam Mohr paper, I notice that he flatly states that methane is 21 times more powerful than carbon dioxide, the figure I have quoted. That multiple of 21 is based on methane molecules persisting in the atmosphere for 12 years; Professor Mohr uses a figure of eight years, which implies that methane could arguably be less than 21 because it would dissipate quicker. In looking over the University of Chicago study, I notice that the authors spend much more time talking about carbon dioxide than methane. Moreover, in discussing nitrous oxide, the authors write that three-quarters of agriculturally produced nitrous oxide comes from nitrogen fertilization of soil. The authors first say the proportion of this that goes toward animal feed is beyond their scope, but then say most of it is due to animal feed. That, then, is an assertion on the part of the authors.

      So there are areas of controversy in these papers; nothing is definitely proved (or disproved) as of yet. They certainly should give us pause for thought and are a necessary part of a legitimate inquiry. But the same can be, and should be, said of papers that place the primary blame on industrial activity. Industrial activity and animal agriculture each pump carbon dioxide, methane and nitrous oxide into the atmosphere. Each are significant contributors to global warming. We do ourselves no favors by prematurely declaring an ongoing debate concluded.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s