– The Trump White House, which has defined itself by a willingness to dismiss scientific findings and propose its own facts, on Friday issued a scientific report that directly contradicts its own climate-change policies.

That sets the stage for a remarkable split-screen political reality in coming years. The administration is widely expected to discount or ignore the report’s detailed findings of the economic strain caused by climate change, even as it continues to cut environmental regulations, while opponents use it to mount legal attacks against the very administration that issued the report.

“This report will be used in court in significant ways,” said Richard L. Revesz, an expert in environmental law at New York University. “I can imagine a lawyer for the Trump administration being asked by a federal judge, ‘How can the federal government acknowledge the seriousness of the problem, and then set aside the rules that protect the American people from the problem?’ And they might squirm around coming up with an answer.”

The 1,656-page National Climate Assessment, which is required by Congress, describes in precise detail how the warming planet will cause hundreds of billions of dollars of damage in coming decades. President Donald Trump has often questioned or mocked the basic science of human-caused climate change, and is now working aggressively to encourage the burning of coal and the increase of greenhouse gas pollution.

Historians and veterans of public service said that it is notable that policymakers didn’t try to soften the report’s conclusions, because it indicates the strength of the administration’s belief that it can ignore the findings in favor of policies driven by political ideology.

“This is a new frontier of disavowance of science, of disdain for facts,” said William K. Reilly, who headed the Environmental Protection Agency under President George H.W. Bush.

A White House statement said the report, started under the Obama administration, was “largely based on the most extreme scenario” of global warming and that the next assessment would provide an opportunity for greater balance.”

In interviews with about a dozen authors of the report, all said that White House officials had not sought to soften or weaken its language.