This is an archived article that was published on sltrib.com in 2017, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

Washington • On what could be a record-hot day, tens of thousands of demonstrators are expected to assemble in Washington on Saturday. Their large-scale climate change protest will mark President Donald Trump's first 100 days in office, which have been punctuated by multiple rollbacks of environmental protections and Obama climate policies.

The People's Climate March, which originated with a massive demonstration in New York in September 2014, picked a symbolically striking day for its 2017 event. Temperatures could exceed 90 degrees and possibly set a record for April 29 in the District of Columbia, which would amplify the movement's message.

Marchers are sure to be further galvanized by a move taken by the Environmental Protection Agency late Friday. The agency announced that it was beginning an overhaul of its website, which included taking down a long-standing site devoted to the science of climate change, which the agency said was "under review." (The EPA did link to a snapshot of how the page looked on Jan. 19, before the Trump administration.)

"There is no Planet B," read a sign held by Eva Gunther of Washington, D.C., as the protest assembled on the National Mall Saturday morning.

"Hang on EPA, the midterms are coming. 2018," read another carried by Kathy Sommer of Stony Brook, N.Y.

The climate event differs from last week's March for Science in its focus and also its participants - only 1 out of 8 planned contingents of Saturday's protest will feature scientific researchers. The rest will include labor activists, indigenous people already facing severe effects from climate change, and children and young people who will live with the effects of climate change longest as the Earth continues to warm.

But there's pretty clearly plenty of overlap.

Ken Hunter, 78, traveled from Charlestown, W.Va. for Saturday morning's march. He also came to Washington for the March for Science last weekend and the Tax March on April 15 - and attended a Women's March in Florida.

"Hell, I haven't marched this much in years," Hunter said with a laugh. "But these are all very important issues and it was important to be out here."

The motivation for the current climate march is clear: The young Trump administration already has moved to roll back former president Barack Obama's signature climate initiative, the Clean Power Plan, and Trump and his team have taken many other actions to weaken environmental protections of air and water, and to enable fossil fuel exploitation on public lands and waters.

The administration is grappling with a major climate policy decision: whether to remain in the Paris climate agreement. Several of Trump's Cabinet picks are advising against following through on his campaign pledge to "cancel" the accord.

It all adds up to a big contrast with the original People's Climate March in 2014. That event was aimed at rallying support for climate change action and preceded by about a year the Paris climate agreement. This event is much more targeted at resisting rollbacks of climate efforts.

Not that that was necessarily intentional: In a press statement, Paul Getsos, national coordinator of the People's Climate Movement, said the event was actually planned "before the election."

Marchers on Saturday plan to gather at the Capitol and then move up Pennsylvania Avenue and "surround" the White House. Celebrity attendees will include Leonardo DiCaprio, Al Gore and Richard Branson.

Organizers told the National Park Service that they expect 50,000 to 100,000 attendees. More than 375 satellite marches are expected around the United States and even more around the world. From Manila to Amsterdam, multiple marches had already begun across the globe Saturday.

The forecast is for temperatures to reach as high as the low 90s. The current record for the date is 91 degrees, while this month already is the warmest April on record for the District of Columbia.

—-

The Washington Post's Joe Heim and Lori Aratani contributed to this report.