KPBS: President Barack Obama speaks by the Sentinel Bridge in the Yosemite Valley, in front of Yosemite Falls which is the highest waterfall in the park at Yosemite National Park, Calif., on June 18, 2016. The Obama family traveled to Yosemite to celebrate the 100th anniversary of the creation of America's national park system.
Scientists Say Climate Change Damaging National Parks
July Fourth is one of the busiest weekends for national parks across the country. But visitors to parks this summer,...