(Washington) About 400 climate experts on Monday signed a letter in support of a U.S. government proposal that envisions more than tripling the social cost of carbon, a key metric used to quantify the damage caused by CO2 emissions.2 notably.
Currently, the cost of one ton of CO2 additional released into the atmosphere is estimated at 51 dollars by the US 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 the reduction of greenhouse gas emissions.
It takes into account the damage caused to property (for example to houses and infrastructures in the face of more frequent floods or fires, etc.), to the health of populations, but also economic losses in the agricultural sector in particular, or even the changes caused on 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 the $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 notably the 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 had published a study in the scientific journal Nature estimating the social price of carbon at $185.