With the announcement this week that Quebec will soon begin promoting “Meatless Mondays,” anti-meat activism got a significant boost. As usual, news stories about the campaign cited sketchy figures from a 2006 United Nations report claiming that livestock producers are responsible for 18 percent of global greenhouse gas emissions. But these pendulums tend to swing back toward sanity eventually. Reporters today are covering new research from University of California-Davis expert Dr. Frank Mitloehner. His message: It’s time to clear the air about meat and global warming.

Mitloehner’s new research shows that while the U.N.’s report shows animal agriculture contributing 18 percent of greenhouse gases (GHGs), here in the U.S. the Environmental Protection Agency’s domestic inventory shows all agriculture contributes 5.8 percent of GHGs. (And California is even lower than that average, with a 2005 state inventory finding the ag sector contributes just 5.4 percent of total GHGs.) As for the veggie-activist claim that livestock farmers are sowing climate doom, the EPA found that the livestock portion of the pie accounts for less than 3 percent of domestic emissions.

And the U.N.’s report did not make a compelling analysis, says Mitloehner, who calls it “a classical apples-and-oranges analogy that truly confused the issue.” While it provided a detailed farm-to-fork analysis of livestock-related emissions, the U.N.’s analysis of transportation sources was nowhere near as thorough. This likely led to an overstatement of agriculture’s impact on the climate.

So what’s a better solution than calling for widespread tofu conversion? The answer: Helping underdeveloped countries to become more energy-efficient with their livestock production. This is especially important considering that global demand for meat is expected to double by 2050. (Sorry, PETA and HSUS.)

How efficient are U.S. livestock producers? As Mitloehner details elsewhere, America’s beef production in 2008 needed 37 million fewer cattle to produce the same amount of meat as in 1975. This increase in efficiency (more meat per head of cattle) has led to less waste and required less feed. And a 2007 study published in the Journal of Animal Sciences found that modern dairy producers require significantly fewer resources than their counterparts six decades ago.

There’s little doubt that the anti-meat Humane Society of the United States, the “Supreme Master” Ching Hai, Paul McCartney, and other vegetarian activists will keep pushing their “go veg” climate campaigns. But if they really care about global warming, they’d do more good by policing the supermarket for “Made in the USA” labels.