The Interagency Working Group on Social Cost of Greenhouse Gases published "Technical Support Document: Social Cost of Carbon, Methane, and Nitrous Oxide: Interim Estimates under Executive Order 13990."
This Technical Support Document (TSD) presents interim estimates of the social cost of carbon, methane, and nitrous oxide developed under Executive Order 13990. These interim values are the same as those developed by the Interagency Working Group (IWG) in 2013 and 2016. The current IWG will take comment on recent developments in the science and economics for use in a more comprehensive update, to be issued by January 2022, which will more fully address the recommendations of the National Academies of Sciences, Engineering, and Medicine as reported in Valuing Climate Damages: Updating Estimation of the Social Cost of Carbon Dioxide (2017) and other pertinent scientific literature. As a part of that request for comment, the IWG will seek comment on the discussion of advances in science and methodology included in this TSD and how those advances can best be incorporated into the revised final estimates.
On January 20, 2021, President Biden issued E.O. 13990 which re-established the IWG and directed it to ensure that social cost of greenhouse gases (SC-GHG) estimates used by the U.S. Government (USG) reflect the best available science and the recommendations of the National Academies (2017) and work towards approaches that take account of climate risk, environmental justice, and intergenerational equity. The IWG was tasked with first reviewing the SC-GHG estimates currently used by the USG and publishing interim estimates within 30 days of the E.O. that reflect the full impact of GHG emissions, including taking global damages into account. In this initial review, the IWG finds that the SC-GHG estimates used since E.O. 13783 fail to reflect the full impact of GHG emissions in multiple ways.
While the IWG works to assess how best to incorporate the latest, peer reviewed science to develop an updated set of SC-GHG estimates, it is setting interim estimates to be the most recent estimates developed by the IWG prior to the group being disbanded in 2017. The IWG concludes that these interim estimates represent the most appropriate estimate of the SC-GHG until the revised estimates have been developed. This update reflects the immediate need to have an operational SC-GHG for use in regulatory benefit-cost analyses and other applications that was developed using a transparent process, peer reviewed methodologies, and the science available at the time of that process. Those estimates were subject to public comment in the context of dozens of proposed rulemakings as well as in a dedicated public comment period in 2013.
At the same time, consistent with its continuing commitment to a transparent process and a desire to move quickly to update SC-GHG estimates to better reflect the recent science, the IWG will be taking comment on how to incorporate the recommendations of the National Academies (2017) and other recent science , including the advances discussed in this TSD, both during the development of the fully updated SC-GHG estimates to be released by January of 2022 and in subsequent updates. The IWG will soon issue a Federal Register notice with a detailed set of requests for public comments on the new information presented in this TSD, as well as other topics and issues the IWG will address as we develop the next set of updates.
TSD link:
https://www.whitehouse.gov/wp-content/uploads/2021/02/TechnicalSupportDocument_SocialCostofCarbonMethaneNitrousOxide.pdf
WH blog by IWG co-chair and CEA member Heather Boushey: "A Return to Science: Evidence-Based Estimates of the Benefits of Reducing Climate Pollution"
https://www.whitehouse.gov/briefing-room/blog/2021/02/26/a-return-to-science-evidence-based-estimates-of-the-benefits-of-reducing-climate-pollution/
As decision-makers develop policies, they must incorporate the very real costs of climate change to current and future generations into their decisions.
One specific tool — called the “social cost of greenhouse gases” — combines climate science and economics to help Federal agencies and the public understand the benefits of reducing greenhouse gas emissions. The metric is a range of estimates, in dollars, of the long-term damage done by one ton of greenhouse gas emissions.
In a first-day executive order on Protecting Public Health and the Environment and Restoring Science To Tackle the Climate Crisis, President Biden reconvened the working group of technical experts from across the Federal Government and instructed them to restore the science- and economics-based approach to estimating climate damages.
The Interagency Working Group — co-chaired by the Office of Science and Technology Policy, Office of Management and Budget, and Council of Economic Advisers — today announced it is replacing the previous Administration’s estimates with the estimates developed prior to 2017, adjusted for inflation. This interim step will enable Federal agencies to immediately and more appropriately account for climate impacts in their decision-making while we continue the process of bringing the best, most up-to-date science and economics to the estimation of the social costs of greenhouse gases.
Today’s step restores three critical aspects of these estimates. First, the estimates put in effect today were subject to an extensive and robust process, including public notice and comment. A 2014 Government Accountability Office (GAO) report also concluded that the Interagency Working Group followed a “consensus-based” approach, relied on peer-reviewed academic literature, and disclosed relevant limitations when finalizing the estimates we are restoring today.
Second, these estimates take global damages into account. COVID-19 has re-emphasized the ways in which events on the other side of the globe can harm us here. Climate impacts abroad can affect the United States in many ways, including through supply chain disruptions, market volatility, and effects on our national security. In addition, climate actions taken by the United States and other countries under the Paris Agreement will benefit all countries, including the United States. Just as we expect and encourage other countries to consider the climate impact of their actions on us, we should take the global benefits of our actions into account.
Third, these estimates use the discount rates (the approach to calculating the present-day value of future climate damages) previously established by the Interagency Working Group. Restoring these rates puts these interim values in better alignment with the intergenerational nature of the climate challenge and the approaches taken in the peer-reviewed literature than the estimates used while the Interagency Working Group was disbanded.
Media coverage:
Washington Post, "Biden is hiking the cost of carbon. It will change how the U.S. tackles global warming. The new policy could shape decisions ranging from fossil fuel leasing to what sort of steel and glass the federal government buys." February 26, 2021
https://www.washingtonpost.com/climate-environment/2021/02/26/biden-cost-climate-change/
Politico, "Biden hikes cost of carbon, easing path for new climate rules. The social cost of carbon could have ripple effects throughout industry." February 26, 2021
https://www.politico.com/news/2021/02/26/biden-carbon-price-climate-change-471787