308-7 Raising the Steaks: Global Warming and Pasture-Raised Beef Production In the United States.



Wednesday, October 19, 2011: 11:45 AM
Henry Gonzalez Convention Center, Room 217C, Concourse Level

Doug Gurian-Sherman, Food and Environment Program, Union of Concerned Scientists, Washington, DC
Pasture beef production is a growing niche market in the United States, and has been discussed as a climate and environment friendly alternative to finishing beef cattle in feedlots. Better data are needed to assess these claims. And because all beef cattle—even those finished in feedlots—spend the first part of their lives on rangeland or pasture, understanding the climate impacts of grazing cattle is broadly relevant. We contribute to this evaluation by reviewing current data on the climate impacts of pasture beef production and the potential to mitigate these impacts.

Beef production in the United States accounts for roughly 2.2 percent of climate change emissions—especially methane from enteric fermentation and nitrous oxide emissions from growing corn for feed and from pasture soils. On the other hand, we find substantial potential to mitigate these impacts by implementing currently available and practical methods. Review of the literature suggests that several best management practices can reduce methane emissions from enteric fermentation by about 15 to 30 percent over common practices. However, methane reduction potential nationwide requires better data on the prevalence of current pasture practices. Adoption of these practices globally could have a larger impact.

It is also important to understand the relative climate impact of pasture beef finishing compared to the currently-predominant CAFO system, because these are often proposed as alternatives. We consider the variation in pasture feed efficiency to illustrate the importance of refining current comparisons of pasture and CAFOs using climate models. The soil carbon sequestration potential of pasture and grain feed crops are also compared.

Finally, we provide recommendations for research and policy that could further reduce the climate impact of pasture-raised beef.

See more from this Division: ASA Section: Environmental Quality
See more from this Session: Management Impact On GHG Emissions and Soil C Sequestration: II