Every Tuesday, students at the University of San Francisco are presented with "low carbon" diet choices in the school cafeteria, according to a story in the San Jose Mercury News. Gone is cheese pizza and hamburgers. Such savory treats are being substituted with options that are equally delicious - like guacamole and cucumber relish - but are produced on farms that release less greenhouse gasses than dairies and livestock operations.
USF is one example of institutions looking at changing food consumption to reduce the amount of greenhouse gases floating into earth's atmosphere. According to the article, the United Nations reported in a 2006 publication, "Livestock's Long Shadow," that the livestock sector is responsible for 37 percent of human-caused methane release, which is 23 times more potent a heat-trapping gas than carbon dioxide. Livestock emit 65 percent of all human-caused nitrous oxide, which is nearly 300 times the potency of carbon dioxide.
Reporter Suzanna Bohen called UC Davis food systems analyst Gail Feenstra to comment on information from the National Cattlemen's Beef Association. The association's spokeswoman said that critics of beef production's ecosystem effect fail to factor in the environmentally beneficial role of grazing cattle. That includes pastureland absorbing carbon dioxide as it regrows after grazing.
"That's debatable," the article paraphased Feenstra. She is embarking on a project to measure greenhouse gases linked to all aspects of producing agricultural products in California, including feed, fertilizer, energy, transportation and numerous other facets.
Perhaps if cattle were grazing only on unfertilized grasslands, they might provide a net carbon benefit, "however, the proportion of cattle raised in this manner is extremely small," Feenstra was quoted.