Earlier this week, we took a look at the public perception plight of cattle feeders. Now Alex Avery, co-author of a significant study on the importance of modern agricultural prctices, offers this clarification on the role of methane production in fed cattle.
He has a valid point, of course. Different feedstuffs digest differently and if we were to produce the same poundage of beef on grass as we do on grain, cattle would produce much more gas. Alas, that is not the real goal of the anti-beef lobby. They want less beef, period. Getting rid of feedyards is jus their idea of step one.
That said, Alex makes his point far better than I can:
I hope you’ll take another look at our report from 2007 on the greenhouse gas (GHG) emissions of grain-fed versus grass-finished beef. The numbers show grain-finishing results in 40% fewer CO2-equivalent GHG emissions per pound of beef than grass-finished. Niman was simply wrong in proclaiming grass-finished better in terms of “climate change” emissions.
I’ve written to the NY Times (including the public editor) and showed them my and two other analyses, and haven’t heard a word back.
Background: My report used;
- third party beef production data (from Iowa State’s Leopold Center for Sustainable Agriculture) and
- UN IPCC greenhouse gas emissions (emissions factors for grain-fed versus grass-fed animals).
- including emissions from fertilizer production for feed corn, (no fertilizer for grass)
- but not including feed transport (which can very significantly), but is often no more than 5-6%.
The UN report – Livestock’s Long Shadow – that says 18% of human emissions are from livestock (1/3 of which is from Amazon destruction for cattle feed) even says that the answer is to increase the digestability of feed (i.e. grain is better as far as greenhouse gas emissions). Less methane from grain, half as much as when feeding on grass.
Last year’s AAAS meeting had a presentation from a grad student at Dalhousie University (Nova Scotia) that noted about 50% fewer GHG emissions per pound in grain finishing versus grass. Also, a German group reported 40% less from grain finished beef.
Here’s what I sent the NYT.
On Saturday, Nicolette Niman self-servingly claimed that meat raised outdoors on pasture have “scant connection” to the carbon dioxide emissions and wrongly claimed the methane emissions aren’t a problem on “traditional farms.” The obvious, and wrong conclusion from these statements is that beef finished on grain-based diets in feedlots are the real greenhouse gas emission problem with meat consumption.
Several independent and comprehensive studies, including my own (see: http://www.cgfi.org/pdfs/nofollow/beef-eco-benefits-paper.pdf), have shown repeatedly that beef finished in feedlots on corn-based diets have 40% to 50% less CO2-equivalent greenhouse gas emissions per pound of beef produced. Thus, the more “climate-friendly” beef option is the grain-finished beef so out of fashion. Why is this so? Because cattle fed on grass produce roughly twice as much methane as cattle fed on grass (eluded to in Niman’s own op-ed), and according to the UN IPCC, methane is 23 times more powerful a greenhouse gas than CO2. Thus, while grain-finished cattle are responsible for higher CO2 and nitrous oxide emissions, this is more than offset by the higher methane emissions.
Why the New York Times refuses to acknowledge this now well established fact, one that was in fact discussed on the NYT own environmental blog, is curious for a paper that claims to be so concerned with accuracy on such important matters.
But please don’t take my word for it, simply ask Nathan Pelletier of Dalhousie University, who presented this reality at the American Association for the Advancement of Science meeting in February of this year, as reported in Science News: http://www.sciencenews.org/view/generic/id/40934/title/Science_%2B_the_Public__AAAS_Climate-friendly_dining_%E2%80%A6_meats
Excerpt from Science News article: Many environmentalists have argued that finishing up the fattening of beef cattle on corn is worse for the environment than cattle that are raised solely on pasture grass. Pelletier says his team’s analysis finds that at least from a climate perspective, the opposite is true. “We do see significant differences in the GHG intensities [of grass vs grain finishing]. It’s roughly on the order of 50 percent higher in grass-finished systems.”
When an audience member questioned whether he had heard that right, that grass-fed cattle have a higher carbon footprint, Pelletier reiterated, “higher. Yes.” The reason: “It’s related to the much higher volumes of feed throughput and associated methane and nitrous-oxide [GHG] emissions.” He added that most pastures were highly managed, and subject to “periodic renovations and also fertilization.” Finally, with grass-fed cattle “there is also a high [grass] trampling rate. So the actual land area that you need to maintain magnifies that [GHG] difference,” Pelletier said.
Or ask the German Institute for Ecological Economy Research, from an article in Der Speigel: http://www.feasta.org/forum/viewtopic.php?t=704
The report from IEER (IOeW in German) is available here: http://www.foodwatch.de/kampagnen__themen/klima/klimastudie_2008/index_ger.html
Excerpt: The production of one kilo of grass-fed beef causes the same amount of emissions as driving 113.4 kilometers (70.4 miles) in a compact car. Because of more intensive production methods, producing one kilo of conventional beef is the equivalent of driving only 70.6 kilometers (43.9 miles).
Hudson Institute’s Center for Global Food Issues