My personal proof of global warming is The (Yale-Harvard) Game. It is always the weekend before Thanksgiving. I remember the late 70s and the 80s, freezing my butt off and needing a parka, sweater, turtleneck and maybe thermal underwear to make it through 5 hours of drinking and watching a football game, especially at the Stadium. The past 20 years or so, I don't think I've worn a parka or thermals. Just my usual fall coat, maybe a turtle neck and a sweater.
Oh, very good second half today, 3 to 4 point game until a minute left, but the winners were the bad guys, 34- 24.