The Trump administration has revoked a scientific finding that climate change is a danger to public health, an idea that President Donald Trump called “a scam.” But repeated scientific studies say it’s a documented and quantifiable harm. The decision from the administration on Thursday reverses a 2009 finding that says warming endangers Americans' lives and health. But researchers have published tens of thousands of peer-reviewed studies on climate and health. Many link warming to more deaths and illness. One study shows U.S. heat deaths have more than doubled since 1999. Other studies tie warming to wildfires, storms, infections, mental health strain, and displacement. Studies also note cold deaths are falling, which can offset heat risks for now.