GREELEY, Colo. – The effects of climate change are not far off challenges for future generations. They are existential problems for everyone alive today.

That’s one big takeaway from the U.S. federal government’s latest roundup of climate science, the National Climate Assessment, now in its fourth iteration.

Released the day after Thanksgiving, the report is unequivocal. In short, declarative sentences that are heavily footnoted, it urgently tells readers that climate change is happening, it’s human-caused and it could make life in the Western U.S. increasingly difficult.

The report is a product of the U.S. Global Change Research Program, an amalgam of 13 federal agencies. Its publication is required by law.