For years, animal rights and welfare groups have maintained that the factory farming of animals for human consumption wreaks havoc on the environment. Now that climate change has become a mainstream issue, they’re taking it up a notch.

Bolstered by a recent United Nations report "stating that the livestock business generates more greenhouse gas emissions than all forms of transportation combined," PETA and the Humane Society of the United States, among others, are putting pressure on environmental groups to come out against meat consumption, and are taking their message directly to an increasingly eco-conscious public.

The New York Times reports:

PETA is outfitting a Hummer with a driver in a chicken suit and a vinyl banner proclaiming meat as the top cause of global warming. It will send the vehicle to the start of the climate forum the White House is sponsoring in Washington on Sept. 27, "and to headquarters of environmental groups, if they don’t start shaping up," [PETA’s Matt A.] Prescott warned.

He said that PETA had written to more than 700 environmental groups, asking them to promote vegetarianism, and that it would soon distribute leaflets that highlight the impact of eating meat on global warming.

"You just cannot be a meat-eating environmentalist," said Mr. Prescott.

As usual, the HSUS is taking a less confrontational tack:

On its Web page and in its literature, the Humane Society has also been highlighting other scientific studies — notably, one that recently came out of the University of Chicago — that, in essence, show that "switching to a plant-based diet does more to curb global warming than switching from an S.U.V. to a Camry," said Paul Shapiro, senior director of the factory farming campaign for the Humane Society.

The society, Mr. Shapiro said, is not only concerned with what happens to domesticated animals, but also with preventing the carnage that global warming could cause to polar bears, seals and other wildlife. "Our mission is to protect animals, and global warming has become an animal welfare issue," he said.

Says Matt Ball, ED of Vegan Outreach: "Al Gore calls global warming an existential risk to humanity, yet it hasn’t prompted him to change his diet or even mention vegetarianism … I guess the environmentalists recognize that it’s a lot easier to ask people to put in a fluorescent light bulb than to learn to cook with tofu."

Image: HSUS via New York Times