The Trump administration’s estimate of the social cost of climate change is seven times lower than the amount used during the Obama administration, according to a Tuesday report by the Government Accountability Office.
The social cost of climate change is the value of the effects of an incremental increase in carbon dioxide emissions, usually measured in dollars per metric ton. The dollar value influences how governments calculate the costs and benefits of energy and environmental regulations and climate change policies.
The metric has become an industry target because of how it has been used to justify stringent regulations.
Under previous estimates, the social cost of carbon was $50 per ton by 2020 and $82 by 2050. Estimates by the Trump administration put the cost at $7 per ton by 2020 and $11 by 2050, the GAO report found.
Both prior and current estimates used 2018 dollars and a 3% discount rate. The difference was that the current federal estimates account only for domestic damages and not global ones, the report said.
‘Very Serious Criticism’
Richard Revesz, Lawrence King professor of law and dean emeritus at NYU School of Law and director of the Institute for Policy Integrity, said the report reads as a “very serious criticism of the Trump administration.”
He said the GAO’s documentation of “ignoring the best science available” will weaken the administration’s efforts to uphold its environmental deregulation in court.
“This is yet another example of how the administration is ignoring science and economics in its policy decisions,” Revesz said. “Pretending that climate change will have virtually no impacts on Americans is completely disingenuous, and the resulting policy failures could have terrible consequences.”
The OMB didn’t immediately respond to a request for comment.
The National Academies of Sciences, Engineering, and Medicine in 2017 recommended updating the methods used to calculate the social cost of carbon to ensure the federal government was using the best available science.
The GAO recommended the White House Office of Management and Budget choose a federal agency that would be responsible carrying out the update the science advisory body called for.
The GAO said the OMB didn’t comment on its recommendation.
“In the absence of action by OMB, the federal agencies may not be using the best available science to complete future analyses,” Alfredo Gomez, director of Natural Resources and Environment for GAO, said in an email.
Part of Broader Climate Views
The changes in handling the social cost of carbon date to the beginning of the Trump administration.
An Interagency Working Group on Social Cost of Carbon was set up in 2009 to develop government-wide estimates of the social cost of carbon. President Donald Trump disbanded it in March 2017 as part of his Executive Order 13783 on energy independence and economic growth. The GAO said that beginning with that executive order, the Trump administration “revoked policies that had identified addressing climate change as a priority.”
The social cost of carbon has been the subject of dozens of legal briefs and public comments in regulatory proceedings. This includes comments submitted by the Institute for Policy Integrity on a March executive order by Oregon Gov. Kate Brown (D) to reduce and regulate greenhouse gas emissions.
The institute recommended using social cost of carbon estimates of the Federal Interagency Working Group under the Obama administration when monetizing the benefits of avoiding greenhouse gases.