YOSEMITE NATIONAL PARK, Calif. — President Barack Obama said Saturday that climate change is already damaging America’s national parks, with rising temperatures causing Yosemite’s meadows to dry out and raising the prospect of a glacier preserve without its glaciers someday.

“Make no mistake. Climate change is no longer just a threat. It’s already a reality,” Obama said from a podium, with Yosemite Falls, one of the world’s tallest at 2,425 feet, as a backdrop.

At the California park, where Obama was spending the weekend with his wife, Michelle, and daughters Malia and Sasha, the president also talked about how a rabbit-like animal known as a pika is being forced further upslope at Yosemite to escape the heat.

“Rising temperatures could mean no more glaciers at Glacier National Park. No more Joshua trees at Joshua Tree National Park,” he said, adding that a changing climate could destroy vital ecosystems in the Everglades and threaten such landmarks as Ellis Island and the Statue of Liberty.

Obama spoke near Yosemite’s Sentinel Bridge, where views of Half Dome, a well-known rock formation in the park, and Yosemite Falls created a picturesque background behind him under a sunny, blue sky.

After a night with his family in a rented cabin in the popular park, Obama stuck to his usual routine by rising early Saturday and heading to a recreation center on the grounds for his daily gym workout.

Obama’s weekend in the great outdoors was planned to encourage more people to appreciate and visit many of the nation’s parks. The National Park Services manages more than 400 sites around the country and celebrates its centennial in August.