Climate experts push for a revised social cost of carbon

Climate experts push for revised social cost of carbon the rise


About 400 climate experts signed a letter on Monday in support of a US government proposal that envisions more than tripling the social cost of carbon, a key metric used to quantify the damage caused by emissions CO2 in particular. 

Currently, the cost of an additional ton of CO2 released into the atmosphere is estimated at 51 dollars by the American administration. A proposal from the US Environmental Protection Agency (EPA) plans to raise it to $190.

“We look forward to these more robust estimates being finalized without delay, so that they can be incorporated into the decision-making of federal agencies,” the experts said in their letter, noting that this cost was certainly still underestimated. . 

The social cost of carbon makes it possible to better guide political decisions in the fight against climate change, by making it possible to compare the benefits derived from certain measures (standards for power plants, etc.) with the expenses incurred. Climate experts agree on its importance in encouraging lower greenhouse gas emissions.

It takes into account damage to property (e.g. to houses and infrastructure in the face of flooding or more frequent fires…), to the health of the population, but also the economic losses in the agricultural sector in particular, or the changes caused to the energy system.

Under the Trump administration, this cost had been reduced to single digits, before being reassessed by the administration of Joe Biden, who set it at $51 while acknowledging that it was probably underestimated. 

The EPA released a preliminary report late last year containing this $190 revision. It also reassesses the social cost of methane.

This report was subject to a public comment period, which ended on Monday. The timing of potential future adoption remains uncertain.

The letter was sent Monday by the Union of Concerned Scientists (UCS). 

Among the signatories are scientists Michael Mann (professor in the Department of Environmental Sciences at the University of Pennsylvania), Andrea Dutton (University of Wisconsin-Madison), Don Wuebbles (University of Illinois), but also economists (Linda Bilmes, Eric Maskin, Gary Yohe)… 

In September 2022, experts published a study in the scientific journal nature estimating the social price of carbon at $185.