Do 'Carbon Offsets' Really Work?

"The companies take millions of dollars collected from their customers and funnel them into carbon-cutting projects, such as tree farms in Ecuador, windmills in Minnesota and no-till fields in Iowa.

In return, customers get to claim the reductions, known as voluntary carbon offsets, as their own. For less than $100 a year, even a Hummer can be pollution-free -- at least on paper.

Driven by guilt, public relations or genuine concern over global warming, tens of thousands of people have purchased offsets to zero out their carbon impact on the planet."

"But the industry is clouded by an approach to carbon accounting that makes it easy to claim reductions that didn't occur."

"The problem is whether the voluntary reductions really exist...Several environmental and clean energy groups have also raised concerns about verifying projects, monitoring their actual carbon reductions and ensuring that each carbon offset is not sold more than once."

"It was a well-intended gesture, but one that some scientists say does carry a price. Offsets are so convenient that they may foster a false sense that global warming can be easily solved when the hard and expensive work remains undone."