I heard that cattle were the problem. Seems like eating more beef might help, though charcoal grilling it (the best way to deal with the more tender cuts, IMHO), probably offsets.
Science is frequently politicized, though realizing this doesn't help analyze things very much. I remember talking about the possibility of global warming back in the summer of 1992 when I was a summer intern at Sandia National Labs in Albuquerque. Back then it wasn't political, I don't think, just something important to try to sort out through a mathematical modeling and statistical analysis. I never worked in the area, unfortunately (or fortunately), so I couldn't tell you whether I thought the models were credible or not. Unless I were to study them very seriously, I couldn't say, and I left academia in 1996, so I'm not likely to. However, as for the pitfalls of mathematical models, I will never forget Carl Sagan saying that if Saddam torched the Kuwaiti oil fields it would lead to conditions somewhat like a "nuclear winter". Another scientist disagreed, said that their models showed no such thing, but Carl responded that they had failed to take account of convection of the soot particles from solar heating. Unfortunately, the experiment was actually tried. Fortunately, Carl was wrong (and I would guess that nobody was happier about it than he). It would seem that there is very little political will to do much about global warming, so our little experiment with virtually unbridled burning of fossil fuels is being tried as well. Let's hope it turns out happily.