WASHINGTON — The Trump administration published a report Friday on climate change from its own scientists that left no doubt about its grim reality and its causes.

So now what?

With every new authoritative scientific study, those concerned about global warming express hope that the mounting weight of evidence might finally convince skeptical politicians to take action.

“How much more dire must reports get before this administration comes to terms with the fact that global climate change caused by human activities is happening now and it poses a growing threat?” said Senator Maggie Hassan, Democrat of New Hampshire.

But there is little reason to think that yet another scientific report will fundamentally shift attitudes on global warming — either among policymakers or the public at large. Researchers have found again and again that attitudes about climate change are shaped far more profoundly by political ideology or by comfort with proposed solutions to global warming than they are by the science itself.