Trump administration set to revoke basis of US climate regulation

The administration of President Donald Trump on Thursday plans to announce the repeal of a scientific finding that greenhouse gas emissions endanger human health, removing the legal basis for federal climate regulations.

The move represents the most sweeping climate change policy rollback by the administration to date, after a string of regulatory cuts and other moves intended to unfetter fossil fuel development and stymie the rollout of clean energy.

Trump has said he believes climate change is a hoax, and has withdrawn the United States from the Paris Agreement, leaving the world’s largest historic contributor to global warming out of international efforts to combat it.

The so-called endangerment finding was first adopted by the United States in 2009, and led the EPA to take action under the Clean Air Act of 1963 to curb emissions of carbon dioxide, methane, and four other heat-trapping air pollutants from vehicles, power plants and other industries.

Its repeal would remove the regulatory requirements to measure, report, certify, and comply with federal greenhouse gas emission standards for cars, but may not initially apply to stationary sources such as power plants, officials told the Wall Street Journal earlier this week.

Reuters was unable to confirm those details.

The transportation and power sectors are each responsible for around a quarter of U.S. greenhouse gas output, according to EPA figures.

While many industry groups back the repeal of stringent vehicle emission standards, they have been reluctant to show public support for rescinding the endangerment finding because of the legal and regulatory uncertainty it could unleash.

Legal experts said the policy reversal could, for example, lead to a surge in lawsuits known as "public nuisance" actions, a pathway that had been blocked following a 2011 Supreme Court ruling that GHG regulation should be left in the hands of the Environmental Protection Agency instead of the courts.

"This may be another classic case where overreach by the Trump administration comes back to bite it," said Robert Percival, a University of Maryland environmental law professor.

Environmental groups have slammed the proposed repeal as a danger to the climate. Future U.S. administrations seeking to regulate greenhouse gas emissions likely would need to reinstate the endangerment finding, a task that could be politically and legally complex.

-Reporting by Valerie Volcovic; Writing by Richard Valdmanis; Editing by Chizu Nomiyama/Reuters