A pivotal figure in climate science died recently. Wallace Smith Broecker, the fellow who popularized the phrase "global warming" in the 1970s, passed away on Monday, February 18, after a long illness. His passing reminds me: there has been a fair amount of talk recently, from rightward pundits, abut the supposed difference between the phrases "global warming" and "climate change." The idea is that the alarmists used to say global warming," but they later decided that they had to be less directional and falsifiable in their alarmism, so they had to start using the phrase "climate change" instead. That talk is nonsense. Indeed, a pivotal paper by Broecker uses one of these phrases in the title, the other in the subtitle: "Climate Change: Are We On the Brink of a Pronounced Global Warming?" The phrases have always both been in use as synonyms. Nobody is in fact deep-sixing one for the other. In the 1990s, in an interview,...