clweber’s Recent Comments

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  Ah, EDHARRIS, I see now that you're pointing to a different Casey/Holden piece that formed the basis for the article I'm referring to:

  J Environ Qual 35:231-239 (2006) compared different types of suckler beef production, while Casey, J. W. and N. M. Holden. 2006. Quantification of GHG Emissions from Sucker-beef Production in Ireland. Agricultural Systems 90: 79-98 was the article I was referring to (my mistake above!). The JEQ article does indeed show (slightly) lower GHG emissions from organic production, at 11.2 kg CO2eq/kg-yr vs. 12.2-13 kg CO2eq/kg-yr for the conventional production schemes, which is still higher than the 10.8 kg CO2/kg-yr mean value calclulated in the Agricultural Systems piece. My apologies for the mis-citation (copy and paste error!)

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  However, again, my point is not that grass-fed is substantially worse than grain-fed but that they're pretty much in the same ball-park GHG-wise, and that the difference between them is in the noise when compared to the difference between beef and chicken (1.4 kg CO2e/kg in the US, according to Pelletier, N. 2008. Environmental performance in the US broiler poultry sector: Life cycle energy use and greenhouse gas, ozone depleting, acidifying and eutrophying emissions. Agricultural Systems 98(2): 67-73.)

  Obviously pastured beef can have much better impacts on many other things, like water and air quality, than CAFO beef, but a substantial GHG advantage can't be had without assuming large amounts of C sequestration and no land use impacts despite the large amounts of land needed.

  On Debunking the meat/climate change myth posted 3 months, 2 weeks ago 92 Responses

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  From Casey and Holden (2006):
  Scenario 1 (standard grass fed practice in Ireland): mean ~11.2 kg CO2eq/kg-yr (9.6-14)
  
  Scenario 3 feedlot operation model, specifically modeled on US production patterns: mean ~ 10.8 kg CO2eq/kg-yr (9.7-13)
  
  Scenario 4: standard grass fed practice but with dairy bred animals (this lowers GHGs because you allocate total GHGs to milk and meat rather than just meat at end of life): ~9 kg CO2eq/kg-yr (7.6-12.5)
  
  Scenario 6: feedlot operation, but with dairy bred animals: ~7.4 kg CO2eq/kg-yr (6.6-9.7)
  
  Scenarios 2 and 5 are similar to 1 and 3 but the animals are slaughtered earlier in life, which limits GHGs due to shorter life but also limits profitability due to less finished weight per cow, so seems unlikely to be adopted on a wide scale. Numbers are similar to feedlot operations, at 10.4 and 7.2 kg CO2eq/kg-yr (8.9-13.2) and (5.8-9.4).
  
  Basically, standard practice pastured produces more GHG than feedlot operation in Ireland; at smaller lifetimes the grass fed can compete in terms of GHGs. However, note the ranges--there is a lot of uncertainty in the numbers and the ranges pretty much mean the situtation is similar in grass fed and grain fed. The differences here are in the noise compared to the difference between beef and chicken/fish/eggs or vegetable protein.
  Subak, S., 1999. Global environmental costs of beef production. Ecological Economics 30, 79–91. also found similar numbers, around 7.4 kg CO2eq/kg-yr for feedlot operations in US.

  On Debunking the meat/climate change myth posted 3 months, 2 weeks ago 92 Responses

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  To answer some questions on the soil carbon issue that have been brought up, a quick answer. Most studies of the life cycle emissions from different food options have not included EITHER the net soil C impacts (net uptake or net emission) OR indirect land use change induced by meat production (which drastically increases the GHG responsibility for meat production, as the Steinfeld FAO report shows) for the following reasons:
  
  1) while it is true that hyper-efficient rotational grazing can have net soil C uptake for some number of years (until saturation occurs), particularly on degraded lands, this is not the industry standard practice for pastured meat as of yet, and most studies take average cases. In truth, to be fair one would have to compare this best case pastured meat with the best case grain fed meat and best case chicken/vegetable protein, and the grain fed and chicken best cases would include methane capture with energy recovery from manure management. This would reduce the impacts from all systems, and again the same results come out with non-ruminant meat and vegetable protein sources winning handily.
  
  2) all net soil C and land use change emissions are reversible. If practices change, any C that has been sucked into soils can be re-emitted as CO2 in very short time spans
  
  3) both are incredibly hard to measure and allocate over relevant time periods--one must make a choice of how many years of uptake or how many years of production over which to allocate the impacts of one-time emissions like deforestation, and assume non-reversibility.

  On Debunking the meat/climate change myth posted 3 months, 2 weeks ago 92 Responses

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  I am somewhat saddened that my beloved grist, home to some of the best climate politics coverage on the web would give such prominence to such an ill-informed and ideological argument that contains several logical fallacies and few peer-reviewed references. As a scientist who has studied this issues closely I can report that the consensus of the peer-reviewed science at this point (and it is difficult to overstate the uncertainties in doing such calculations, but nevertheless. . . ) is the exact opposite of this. It is indeed the meat itself, when it comes to ruminant meat production at least (chicken and fish are a different story) and not the production patterns that matter. 

  The pastured beef vs. grain-fed beef question has been studied by several life cycle analysts and every article I have seen has said the same: grain-fed beef produces less greenhouse gases than grass-fed beef. It is counter-intuitive and a bit shocking, but this is the consensus at this point. Although grass fed animals do not reuqire the CO2 and nitrous oxide (NOT NO2 as the author seems to believe) to produce and move the grain that is fed to the grain-fed animamls in the fattening stage, this benefit is more than offset by increased digestion-related methane from a grass fed diet and more importantly, the longer life burping methane that the grass-fed animals need to get to market.

  There are certainly plenty of other sustainability questions related to CAFO-produced meat, including water and air pollution, loss of farming jobs and culture, and many others. but there are no climate benefits to eating grass fed vs. grain fed beef. They are both bad for climate change, and equally so, within the uncertainties necessary to do the calculation. This doesn't mean that everyone needs to go vegetarian--chicken and many forms of fish produce 10 times less greenhouse gases than either type of beef. (I myself, for full disclosure, am not vegetarian)

  if you're interested in reading more on this interesting issue see some of the citations below.

   

  Avery, A. and D. Avery. 2008. Beef Production and Greenhouse Gas Emissions. Environ Health Perspectives 116(9): A374-A375.

  Casey, J. W. and N. M. Holden. 2006. Greenhouse Gas Emissions from Conventional, Agri-environmental Scheme, and Organic Irish Suckler-beef Units. J Environ Qual. 35: 231-239.

  Steinfeld, H., P. Gerber, T. Wassenaar, V. Castel, M. Rosales, and C. de Haan. 2006. Livestock's Long Shadow: Environmental Issues and Options. Rome: United Nations Food and Agriculture Organization. 

  Weber, C. L. and H. S. Matthews. 2008. Food-Miles and the Relative Climate Impacts of Food Choices in the United States. Environ. Sci. Technol 42(10): 3508-3513.

  On Debunking the meat/climate change myth posted 3 months, 2 weeks ago 92 Responses

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  there's a "Cap" in Cap & Auction

  Responding to GL above: "If it 100% of permits are auctioned, then there is no almost no trade. Because permits are generally bought as needed. So secondary markets are small to non-existent. Please don't confuse cap n' trade with cap n' auction.  The difference is critical."

  The whole point of Cap+Trade or Cap+Auction is the cap. Ignoring for a minute the debate between carbon taxation and C+T or C+A (this is where the real debate should be, as the Stern Report elegantly argues) the cap in either system is arbitrary and the major lever of the entire policy. Permits cannot simply be "bought as needed" unless the cap is unreasonably high. Most of the proposals out there, including Obama's, talk about capping at some moderately reduced level in the short-term (up to 2020) and reducing it drastically in the long-term (mostly defined as 2050), as investment and R+D make it more economically feasible to move away from current energy and production practices. Thus, with limited amounts of emissions allocations available, buyers are forced into secondary markets. This is the entire point of either C+T or C+A--the difference between them lies in initial allocation of emissions, again as argued by Stern. On Thoughts and reactions on Obama's bold new energy proposal posted 2 years, 1 month ago 21 Responses