"The Biden administration is reverting to an Obama-era method of calculating the cost of greenhouse gases—a move that industry is almost certain to challenge.

The social cost of carbon is the estimated harm to society of releasing carbon dioxide—the main greenhouse gas—into the atmosphere. It has been used to shape dozens of energy-related regulations.

The Biden approach, which pegs the social cost of carbon at $51 a ton for 2021 after adjusting future costs at a 3% discount rate, replaces a Trump-era method that was as low as $1. The new figure will be used on an interim basis while an interagency working group readies a “more complete update” expected in early 2022, an administration official who spoke on condition of anonymity said Friday."

Stephen Lee and Courtney Rozen report for Bloomberg Environment February 26, 2021. [2]