"If Democrat Joe Biden defeats President Trump this November, his EPA will have a blank slate for writing climate rules.
Because the Trump administration spent 3 ½ years demolishing its predecessor's Climate Action Plan, Biden's team would have an opening to update rules for carbon, methane and hydrofluorocarbons that would exceed their Obama-era counterparts or be more tailored to the political, judicial and economic realities of the 2020s.
To be sure, a departing Trump EPA would leave finalized rules for power plant carbon, vehicle fuel economy, and oil and gas development, among other things, but most of those regulations haven't faced court reviews, allowing an incoming administration to ask that they be returned to the agency."