Jonathan Teller-Elsberg  @  ChelseaGreen

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Meat: carbon emissions, carbon sequestration, ethics, economics.

Posted on Thursday, July 30th, 2009 at 4:59 pm by Jonathan Teller-Elsberg

Ezra Klein's column yesterday, partially cross-posted on his blog (wherein lie the comments), is on the issue of meat: that the production of meat is a very large contributor to global warming and that people should therefore consider reducing their consumption of meat and but that people take their meat eating to be such a personal thing that the political system is incapable of addressing it — unlike the potential for legislation that would reduce the use of fossil fuels. In other words, as hard as it is to get a carbon tax or cap-and-trade system through American politics, it's even harder to get American politics to address the contribution of animal agriculture to global warming.

I commented at his blog (as "JonathanTE") on two points. First, that "meat" is a broad category and that there's good reason to believe that it is possible to raise animals in a way that is actually climate friendly. Second, that some kind of fossil fuel policy will address at least some portion of the greenhouse gas emissions that do arise from animal agriculture. There would certainly be loopholes left in the system (not inevitably, but in practice), but meat production wouldn't be wholly immune to pending climate policies. As part of my comment, I linked to this article on Treehugger on the topic, which itself had generated a great deal of gnashing commentary. Biking home from work last night, I couldn't stop thinking about some of what I'd read in all of this debating, and so here I am hashing out my thoughts before the entire digital world.

There were two main categories of negative commentary.

  1. How can meat (and dairy) production possibly be done without being climate-harmful? Everyone who knows anything supposedly knows that meat (and dairy) are always and everywhere sources of greenhouse emissions above and beyond any positives involved.
  2. Even if animals can be raised in a climate friendly way, that still totally ignores the immorality of raising animals to kill them. Those who claim to care enough about the Earth and its diversity of organisms to want to halt global warming should care enough to stop killing many of those same organisms for the sake of a tasty meal.

Regarding the first issue, I should say up front that I am far, far from being an expert on this. Nonetheless, I've gleaned a little bit of knowledge here and there. So while it may seem counter intuitive that under the right circumstances animal husbandry can be a climate-positive action, truth is often counter intuitive. I mean, 40 years ago, how many people would have believed that it was even physically possible for humans to massively disrupt the entire climate (absent nuclear war), let alone believe that such disruption was actively in progress? But for those who can't even imagine how climate-friendly animal husbandry can occur, here are some quick points.

There is more carbon stored in the Earth's soils than in its plants. Wikipedia's article on soil carbon lists the estimate that "Between 1200 and 1800 Gt [gigatons] of carbon is stored in soils worldwide, twice the amount that is stored in all terrestrial plants." The article on carbon puts that in additional context, saying that all the carbon in coal and petroleum reserves combined amounts to 1050 Gt (annoyingly, they don't list natural gas*), and that the atmosphere contains all of 810 Gt. In other words, while preserving and planting trees is a good thing, generally speaking, in terms of volume, protecting and enhancing soils is a bigger deal.

[* So I've attempted to do an estimate myself. Very roughly, it seems there's about 180 gigatons of carbon contained in the world's natural gas. You can see my sources and calculations here (Excel .xls file). Unlike the estimates for coal and petroleum above, I've used estimates that combine proven reserves of natural gas with predictions of the amount of gas that will be discovered. My reasoning is that, while coal and petroleum don't cause problems in the climate unless and until they are extracted and burned, there's a bunch of natural gas out there frozen into the permafrost and in methane hydrates on sea floors that threatens to spontaneously evaporate into the atmosphere as a result of ongoing global warming. So that carbon might enter the global warming equation whether or not we burn it first. Anyhow, putting it all together, that means total relevant fossil carbon contains something like 1,230 Gt of carbon vs. between 1,200 and 1,800 Gt in soils. I don't know about you, but I was shocked the first time I learned that soils contain more carbon that either the atmosphere or all terrestrial plants combined or all fossil fuels combined.]

Most carbon in soils gets there through biologic means. Plants absorb carbon dioxide and some of that carbon ends up in the plants' cells. Plants secrete carbon-containing substances into the soil through their roots, and when a plant dies or sloughs off parts of itself, these carbon-containing bits of plant matter enter into the soil. Or animals consume parts of plants, absorb some of the carbon into their own bodies, breathe some of the carbon into the atmosphere, and poop some of the carbon onto the ground. From dead animal bodies and animal feces, more carbon enters into the soil. Soil-based organisms, from worms to insects to fungi to bacteria (and others), churn through all this stuff and some fraction of the carbon entering into the process ends up becoming a part of the soil proper.

As I understand it, there's something of a symbiotic relationship that happens, sometimes, between large grazing animals (like cattle), the grasses they consume, and the soil organisms. Remember how the U.S. midwest prairies had such amazing, deep topsoil when European Americans started moving into the area? That was due, in no small part (or so I am led to believe), to the fact that bison and other animals were there. The chewing of the prairie grasses down to stubs, as well as the transformation of grasses into manure, as well as the action of hooves on the surface of the ground all contributed to the formation of new topsoil that would not have happened otherwise. Farmers and ranchers can imitate that process through certain "holistic" grazing methods with cattle and other large herbivores. I recently talked with a passionate dairyman who has been experimenting with all of this. He told me that in one of his experimental pastures, he has seen the creation of 7 inches of new topsoil formed in just the past two years. (I think it was two years; might have been as many as three or as few as one.)  That's freakin' amazing! And more to the point, it represents a massive sequestration of carbon out of the atmosphere and into his soils. So says the website Carbon Farmers of America, "If the American people were to restore the soil fertility of the Great Plains that we have destroyed in the last 150 years, atmospheric levels of carbon dioxide would be reduced to near pre-industrial levels."

Will it actually work out that way? I don't know. But it certainly is, at very minimum, plausible that domestic animals can be raised in such a way as to help alleviate global warming rather than exacerbate it, and all on existing grazing lands — so no more clearing of forests or junk like that.

On to commenter issue numero dos: Is that any reason to kill animals or otherwise mistreat them?

Maybe, maybe not. I do not myself entirely ascribe to an animal rights philosophy that tells me humans ought not utilize animals in any way. I think there are perfectly legitimate arguments in that direction. I also think there are legitimate counter arguments. (I also am not bothered by strident vegan philosophy — I have quite a bit of sympathy for the quandry people find themselves in when they believe that murder, or its equivalent, is being done. Why should they stay silent, even if the noise they raise is "annoying" to those who are engaged in the ostensibly murderous conspiracy?)

But this does lead me to think of some of the economics of the situation. It's like this:

  • Global warming is upon us, and that it's mostly caused by humans burning fossil fuels and messing up soils and forests and such.
  • Global warming is getting worse and will probably be devastating both to human societies and to a myriad of non-human ecosystems; it will cause a massive wave of extinctions that rivals anything the planet has ever undergone before.
  • Billions and trillions of living things dying due to global warming is bad.
  • Utilizing domesticated animals allows us to sequester carbon from out of the atmosphere and into newly formed (actually, resuscitated) topsoil. This is one of the few possibilities available to humanity to not only reduce the severity of ongoing global warming, but actually to halt it and reign it back in, over the course of some decades.
  • Farmers and ranchers won't/can't do this if they can't make a living by managing the herds that are integral to the process.
  • So how can it be economically feasible to promote this solution, partial though it may be, to the global warming crisis?

The path of least economic resistance is to have those farmers and ranchers go with the otherwise existing flow: sell their animals and animal products as meat, dairy, etc. That's not the only conceivable solution. In principle, the government could pay "park rangers" to manage herds of large herbivores, whether cattle or bison or whathaveyou, to do this carbon sequestration thing. The animals wouldn't have to be slaughtered or have anything else done to them other than be herded in whatever manner works best to sequester carbon into new soils. People could individually choose to pay "carbon farmers" to follow these methods, including such farmers who pledge not to induce any premature death in their animals. Probably there are other arrangements that would work as well. But all of these — aside from farmers/ranchers culling their herds for meat/dairy/etc. — are pretty much pie in the sky. Possible in theory, but in practice just ain't never gonna happen.

Personally, I'm hopeful that this soil-carbon sequestration thing pans out, that the research into it proves that it really does work and that it can work on a scale that really matters. And if that happens, that puts the bleeding hearts among us (myself moderately included) in a bit of an ethical pickle. As far as I can tell, the only way that's vaguely economically realistic that this method would be implemented on a meaningful scale is if the animals being used also are culled for meat and dairy. Failure to do so might avoid the inducement of suffering on some set of animals in the short run, while helping to guarantee the inducement (through ongoing global warming) of suffering on other sets of animals in the medium and long run. Also people. The only way to have the vegan cake and eat it too, assuming my presentation of the background material is roughly correct, would be to induce some kind of ethical/economic revolution so that people are somehow paid a living wage to manage animals in a pro-carbon-sequestration manner without their having to cull the animals to gain any part of that wage. Of all the different economic revolutions in the offing, that's not one I'd bet much on succeeding.

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