President Trump and the head of the EPA announced a major change for greenhouse gas emissions, repealing what is known as the "endangerment finding,"​ which provides the underpinning for federal government environmental regulations.

Valerie Volcovici covers U.S. climate and energy policy from Washington, DC.

The 2009 "endangerment finding" was a determination under then-president Barack Obama that six greenhouse gases threaten public health and welfare by fueling climate change.