Demonstrators sit on the ground along Pennsylvania Ave. in front of the White House in Washington, Saturday, April 29, 2017, during a demonstration and march. Thousands of people gathered across the country to march in protest of President Donald Trump's environmental policies, which have included rolling back restrictions on mining, oil drilling and greenhouse gas emissions at coal-fired power plants. The demonstrators sat down for 100 seconds to mark President Trump's first 100 days in office. (AP Photo/Pablo Martinez Monsivais)
Demonstrators sit on the ground along Pennsylvania Ave. in front of the White House in Washington, Saturday, April 29, 2017, during a demonstration and march. Thousands of people gathered across the country to march in protest of President Donald Trump's environmental policies, which have included rolling back restrictions on mining, oil drilling and greenhouse gas emissions at coal-fired power plants. The demonstrators sat down for 100 seconds to mark President Trump's first 100 days in office. (AP Photo/Pablo Martinez Monsivais) Credit: Pablo Martinez Monsivais

The Environmental Protection Agency announced Friday that its website would be “undergoing changes” to better represent the new direction the agency is taking, triggering the removal of several agency websites containing detailed climate data and scientific information.

One of the websites that appeared to be gone had been cited to challenge statements made by the EPA’s new administrator, Scott Pruitt. Another provided detailed information on the previous administration’s Clean Power Plan.

The changes came less than 24 hours before thousands of protesters were to march in Washington and around the country in support of political action to push back against the Trump administration’s rollbacks of former president Barack Obama’s climate policies.

“As EPA renews its commitment to human health and clean air, land and water, our website needs to reflect the views of the leadership of the agency,” J.P. Freire, the agency’s associate administrator for public affairs, said in a statement. “We want to eliminate confusion by removing outdated language first and making room to discuss how we’re protecting the environment and human health by partnering with states and working within the law.”

Yet the overhaul appears to include not only policy-related changes but also scrutiny of a scientific Web page that has existed for nearly 20 years, and that explained climate change and how it worked.

“The EPA’s climate site includes important summaries of climate science and indicators that clearly and unmistakably explain and document the impacts we are having on our planet,” Texas Tech University climate scientist Katharine Hayhoe said. “It’s hard to understand why facts require revision.”

In its press statement, the EPA said that “the first page to be updated is a page reflecting President Trump’s Executive Order on Energy Independence, which calls for a review of the so-called Clean Power Plan.”

David Doniger, director of the climate and clean air program for the Natural Resources Defense Council, tweeted Friday, “Cleansing has begun. EPA website scrubbed of pages on “so-called” Clean Power Plan. Now only alternative facts.”