4. White House criticizes its climate report as "not based on facts"

White House press secretary Sarah Sanders criticized the new climate report that the Trump administration published on Black Friday, saying its conclusions were "based on the most extreme model scenario" and were not based on "facts."

The big picture: The report, known as the Fourth National Climate Assessment, warns that the U.S. will suffer increasingly deadly and costly climate change impacts if greenhouse gas emissions are not sharply reduced in the next decade and more aggressive actions are not taken to adapt to extreme weather events and other climate impacts.

Background: On Monday, President Donald Trump told reporters he did not believe the report's conclusions, even though the findings were the product of work overseen by scientists and officials in his own administration.

"We think this is the most extreme version, and it's not based on facts. It's not data driven. We'd like to see something that is more data driven. It's based on modeling, which is extremely hard to do when you're talking about the climate."

Reality check: The report does include observational data, everything from the amount of carbon dioxide in the air to the melting rate of Greenland's ice cap, along with cutting-edge computer model scenarios that simulate how climate change may play out.

• Scientists who wrote the report have been pushing back at arguments by the White House and others, who have said that it's alarmist in its conclusions.

The report underwent extensive peer review and incorporated feedback from the public, in the form of about 10,000 comments.

Go deeper:

• New climate report warns of increasingly dire risks to U.S.
• Special report: A 30-year alarm on the reality of climate change
• The Black Friday climate report