Do Airline Offset Programs Really Reduce Your Carbon Footprint?

Carbon offset programs have become ubiquitous. You’ve probably seen them as check-box options when booking flights: Click here to upgrade to a premium seat. Click here to cancel your greenhouse gas emissions.

It’s an appealing proposition — the promise that, for a trivial amount of money, you can go about your business with no climate guilt. But if it sounds too good to be true, that’s because, at least for now, it is.

The New York Times asked readers this spring to submit their questions about climate change, and several asked about carbon offsets. How do they work? Do they work at all, or, as one reader put it, “is it just guilt money?”