Imagine telling a farmer that his cows fart too much and that he must do something about it. If you or I did that, his reaction would be laughter followed perhaps by the click-click of a shotgun and a booming, "Get off my land!" If some stuffed-shirt politician were to tell him the same -- well, I dread to think what his response might be.

Which means British Environment Secretary David Miliband had his work cut out, then, for on January third he had the unenviable task of addressing a farmers' conference with the news that they could be penalized if they do not stop their animals from farting so much methane gas [1].

That's because agriculture now contributes 7% of all greenhouse gas emissions and more than a third of all emissions of methane. Furthermore, as John Vidal of The Guardian writes, agriculture accounts for 67% of British nitrous oxide emissions [2].

So what can be done? Well, in New Zealand, according to Vidal, this has led to politicians ruminating a fart tax. Miliband was threatening the same.

Now that we're talking money, let's consider seriously the scale of the problem. According to a United Nations Food and Agriculture Organization report [3], "Cattle-rearing generates more greenhouse gases, as measured in CO2 equivalent, than transportation." Hang on a minute! All those cars, trucks, and SUVs stuck in traffic jams in smog-laden cities all across the developed world -- and cows produce more carbon dioxide? Now that's alarming!

But politicians need not necessarily jump straight to a fart tax. The UN's FAO outlines a number of ways to mitigate the effect of agriculture on greenhouse gas emissions, including increasing the efficiency of livestock production and feed crop agriculture; improving animals' diets to reduce enteric fermentation and consequent methane emissions; and setting up biogas plant initiatives to recycle manure.

Since cows are living things and cars are man-made, here is the question: in order to keep us in meat and milk, should we cut down on our fossil fuel usage, even though transportation be the lesser contributor? Or should we stop farming so much and continue to use our planes, trains, and automobiles? Or should we wake up and think, "Crikey, cattle produce more gas than transportation -- we really have gone too far with this intensive farming!"? Or should we simply not give a cow pat about the consequences?

If the situation is serious enough to send politicians thinking about taxing farmers for flatulent fauna, then I suppose we have to decide which is more essential: the hamburger or the Hummer?