Okay, cows fart and release lots of methane. And we keep cows around for milk, cheese, and other dairy stuff that come from cows. Oh, and we eat them too. And that seems to be the issue as far as global warming is concerned.
However, the real issue seems to be deforestation - not their fart or anything like that. But while this makes a lot of sense, there is an issue that a lot of entrenched interests will fight tooth and nail over - not in the least, consumers who love beef.
Raising the point to the consumers, politicians, farmers about the inefficiency of raising cows, which takes up 60% of the agricultural land and only get back 5% of the protein while feeding only 2% of the world, ain't gonna work. Burgers are just soooo good! (I'm a vegetarian by the way).
I think the only way to address this is one day when we can get our meat products grown in labs or special facilities and won't have to raise animals to satiate our carnivorous appetites. What am I talking about? There are already efforts underway to find ways to clone meat products in labs. I think that is where we are going anyway.
USA Today reported back in Feb that we should have the first lab-grown burger by fall, a couple of months from now. Even if it works - the greasiness, taste, and texture is the same as a patty now, it'll be years if not decades before this takes off - to be joined by chicken, pork, etc.
Until then, the protection of the environment is best served by focusing on other efforts. That's just the reality today.