The nation's leading agricultural state is now targeting greenhouse gases produced by dairy cows and other livestock.Ranching cattle has a long history in California, as it was the primary land use under the Spanish, and then the Mexican colonization.
Despite strong opposition from farmers, Gov. Jerry Brown signed legislation in September that for the first time regulates heat-trapping gases from livestock operations and landfills.
Cattle and other farm animals are major sources of methane, a greenhouse gas many times more potent than carbon dioxide as a heat-trapping gas. Methane is released when they belch, pass gas and make manure.
"If we can reduce emissions of methane, we can really help to slow global warming," said Ryan McCarthy, a science adviser for the California Air Resources Board, which is drawing up rules to implement the new law.
Livestock are responsible for 14.5 percent of human-induced greenhouse gas emissions, with beef and dairy production accounting for the bulk of it, according to a 2013 United Nations report.
Yes, methane is a greenhouse gas, and more potent than CO2, but it has a short lifetime in the atmosphere by comparison, and its concentration is so much lower that it constitutes a small fraction of the greenhouse atmospheric forcing. Because of it's short term persistence in the atmosphere, concentrations are not rising especially rapidly, and if anything, it's rate of increase is declining.
Can we forbid politicians from producing methane, or at least ration them?