In 2007, Matt Yglesias went to the Smithsonian Museum of Natural History and found an “outdated panel pushing concern about global cooling based on some highly speculative 1970s-era science”:
Over two years ago, this display was flagged with a small sign warning that the exhibit in question was being updated to reflect current science. But I went back to the museum yesterday, and it’s still there! A number of other displays in the museum do reflect an accurate understanding of the climate change situation, so it’s not as if the people running the museum don’t know what’s going on. So I don’t understand why they can’t change this.