On President Trump's 100th day in office, thousands of climate activists descended on Washington, D.C., to send the president a message — climate change is real.

Demonstrators braved temperatures above the 90s Saturday to march down Pennsylvania Avenue, chanting "water is life" and "keep it in the soil, can't drink oil!" The gathering, already a familiar sight during Trump's nascent presidency, came together under the banner of the People's Climate March.

Participants surrounded the White House complex and staged a choreographed sit-in, beating their chests 100 times to symbolize both the president's time in office and the heartbeat of the environmental movement. Trump was in residence at the time.

The Sierra Club helped organize the event, which drew celebrities like Leonardo DiCaprio, former vice president Al Gore and climate and clean water activists like Mari Copeny, best known as Little Miss Flint.

climate tweet

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Several demonstrators said they were inspired to march by new reports that the Environmental Protection Agency (EPA) removed references to climate change from its website late Friday night. Pages once devoted to climate change and tracking data on global warming, now say that the site is being updated "to reflect EPA's priorities under the leadership of President Trump and Administrator Pruitt."

EPA administrator Scott Pruitt has previously said he does not believe carbon dioxide is a primary contributor to global warming, bucking decades of scientific research confirming the impacts of emissions on the environment.

Pruitt rose to prominence as Oklahoma's attorney general by suing the agency he now heads 14 times for its efforts to impose regulations on air pollution and mercury.

Sister climate marches were also held in Denver, Chicago and San Francisco and around the world, including London and Lisbon, Portugal.

Throughout his campaign, Trump frequently scoffed at the idea that global warming is a threat to the environment, pledging to cancel the "billions in global warming payments to the United Nations" and pull out of the Paris Agreement.

"I keep hearing about global warming, now they'll say: 'He doesn't understand this is a worldwide problem,'" Trump said, adopting a mocking voice during an April 2016 campaign stop in Rochester, New York.

Here's a look at some of the highlights from the march:

People's tweet

Flint tweet

Joe tweet