Earlier this month, President Trump formally withdrew the United States from the 2015 Paris climate change accord, in which 195 nations agreed to voluntary steps to reduce the emissions of carbon dioxide and other gases released by burning gasoline and coal - emissions that cause global warming. Some of the strongest opposition to the move in the U.S. came from business leaders, who had urged the administration to stay with the accord. In the wake of Trump's decision, announced in June, hundreds of companies, including retail behemoth Wal-Mart and candy maker Mars, re-pledged to meet fossil fuel reduction targets recommended by scientists. The companies say the tactics will ultimately lower business costs and ebb the effects of climate change on supply chains. NewsHour Weekend Special Correspondent Stephanie Sy reports on how some big companies are leading the way to combat climate change, with or without government action.