PolitiFact: Most people have heard about what will happen if humans keep pumping large amounts of carbon dioxide into the air as we burn more fossil fuels, including warmer temperatures, melting polar caps, rising sea levels, stronger storms and big changes in the types of plants and animals that can survive and thrive in particular regions of the world.
"But wait," as an evil TV pitchman might gleefully declare, "there's more."
On June 12, 2013, U.S. Sen. Sheldon Whitehouse, a Democrat from Rhode Island,...