A few days ago, The Washington Post had a piece noting that the financial crisis hasn't really crimped the market for carbon offsets—many consumers are still willing to tack an additional $12 on a cross-country flight or $80 on a wedding to pay for some emissions-reducing project somewhere and alleviate their guilt over spewing so much carbon. But the piece also had a perfect anecdote to illustrate just how ludicrous many of these "offset" projects are:

In the western Virginia town of Christiansburg, the operators of a landfill sell carbon offsets tied to a project that captures methane, a powerful greenhouse pollutant, and burn it in a tall orange flare. They've made $43,000 on the Chicago Climate Exchange in just a couple of months.

But that project was put in long before the offsets were sold and for a different reason: to keep dangerous gases from accumulating in a capped landfill. So if the offset market dried up completely?

Nothing would change.

The money "is gravy to us right now," said Alan Cummins, executive director of the regional authority that runs the landfill. Even without it, he said, "we would always continue to flare."

That's insane. The GAO recently found that the offset market—which could be as large as $100 million—was so opaque and loosely regulated that "it is difficult for consumers to determine the quality of the offsets they purchase." If your offsets are going toward a new wind farm, how do you know that that wind farm wouldn't have been built anyway? If the offsets are being used to plant trees, can you be sure that that's a true offset—what if the tree burns down next year? (And what if planting trees in certain deciduous regions can actually increase warming, as some studies have found?) If the offsets are used to pay someone not to cut down a forest somewhere, how do you know the logger won't just take the money and go cut down some other forest somewhere else? That doesn't mean offsets are totally unworkable, but they certainly need a great deal more scrutiny than is happening right now.

--Bradford Plumer