Example 2: Our hotel room was so cold last night, it was a damn nuclear winter.
It goes like this: the fires produced by the nuclear bombing of targets would inject large amounts of smoke into the atmosphere. The smoke would coalesce into a layer that would block sunlight from reaching Earth's surface. A massive drop in temperatures would result. Here's where the scare tactics kick in: the lack of sunlight would deprive plants of vital energy, causing an extinction event.
This sob story was busted in a 1986 paper called "Nuclear Winter Reappraised." However, the paper was ignored, and fear of nuclear winter continues to subsist.