To meet the Biden administration’s emissions targets, the United States needs to expand and preserve forests to soak up climate-warming carbon dioxide.

The same principle is behind California’s forest offset program: Major polluters in the state can pay forest owners to maintain their land in exchange for carbon credits, allowing net emissions to stay within the cap set by the state.

But there’s an accounting issue. The state’s program has generated more than $20 million “ghost credits” that don’t achieve real climate benefits, letting annual emissions equal to 8.5 million cars escape unaccounted for.

Here & Now‘s Peter O’Dowd talks with Lisa Song, climate reporter for ProPublica who reported the story with the MIT Technology Review.

This article was originally published on WBUR.org.

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