President Donald Trump's administration on Tuesday proposed revoking a scientific finding that has long been the central basis for U.S. action to regulate greenhouse gas emissions and fight climate change. The proposed Environmental Protection Agency rule rescinds a 2009 declaration that determined that carbon dioxide and other greenhouse gases endanger public health and welfare. The “endangerment finding” is the legal underpinning of a host of climate regulations under the Clean Air Act for motor vehicles, power plants and other pollution sources that are heating the planet.