Trump revokes landmark ruling that greenhouse gases endanger public health

US President Donald Trump has reversed a key Obama-era scientific ruling that underpins all federal actions on curbing planet-warming gases.

The so-called 2009 "endangerment finding" concluded that a range of greenhouse gases were a threat to public health. It's become the legal bedrock of federal efforts to rein in emissions, especially in vehicles.

The White House called the reversal the "largest deregulation in American history", saying it would make cars cheaper, bringing down costs for automakers by $2,400 per vehicle. read more