"It's not easy being green" isn't just the lament of Kermit the Frog, it's the dilemma of carbon-crunching greeniacs everywhere.

At least that's the sanctimonious cri de coeur of Seattle Post-Intelligencer blogger Curt Milton:

What's your carbon footprint? How much carbon does your lifestyle emit every year? Can you reduce your carbon footprint?

Thanks to Al Gore (and a lot of other forward-thinking people), carbon is on everyone's mind. The more carbon we emit, the more the Earth's atmosphere heats up. And that, as we all know, is a bad thing.

But, as Michael Specter writes in the Feb. 25 New Yorker, reducing your carbon footprint isn't that easy. And what seem like simple solutions (eating food that is grown close to home) aren't always the best ideas when the whole carbon equation is considered.