The higher the number, the greater the government’s justification for compelling polluters to reduce the emissions that are dangerously heating the planet. During the Obama administration, White House economists calculated the social cost of carbon at $42 a ton. The Trump administration lowered it to less than $5 a ton. Under President Biden, the cost was returned to Obama levels, adjusted for inflation and set at $51.
The new estimate of the social cost of carbon, making its debut in a legally binding federal regulation, is almost four times that amount: $190 a ton.
Got a source, and also how you go about keeping yourself updated on that number
The full article is paywalled, but the abstract of this meta-analysis states “In the past 10 years, estimates of the social cost of carbon have increased from US$9 per tCO2 to US$40 per tCO2 for a high discount rate and from US$122 per tCO2 to US$525 per tCO2 for a low discount rate.” Published May 15 of this year.