None. There was not ever widespread anticipation of global cooling. There was one (1) mass-market magazine article about it that the dupes of fossil fuel propaganda campaigns have been pointing to for years. Rush Limbaugh talked about it constantly in the 1990s, then someone photoshopped up a bunch of fake magazine covers supposedly from the 1970s and your uncle, who is an idiot, has been forwarding those to everyone since.
The only underlying science was some debate about whether air pollution, the kind you can see and scrape off your skin, was going to be so bad that it would offset the greenhouse effect. But Nixon effectively ended that debate with the Clean Air Act.
There was more than one mass-market magazine article. There were no mass-market magazine cover stories, and yes there are fakes going around of those. There were also newspaper articles on it regularly throughout the 1970's. As well as numerous works of science fiction, and TV episodes like "in Search of...The Coming Ice Age" from 1978 narrated by Leonard Nimoy: https://www.youtube.com/watch?v=1kGB5MMIAVA.
The science it was based on, of course, was the fact that ice ages are cyclical and we are well towards what would typically be the end of an interglacial period:
"the last four interglacials lasted over ~20,000 years with the warmest portion being a relatively stable period of 10,000 to 15,000 years duration. This is consistent with what is seen in the Vostok ice core from Antarctica and several records of sea level high stands. These data suggest that an equally long duration should be inferred for the current interglacial period as well. Work in progress on Devils Hole data for the period 60,000 to 5,000 years ago indicates that current interglacial temperature conditions may have already persisted for 17,000 years."
You also had the fact that some of the coldest (and snowiest) winters on record in the US were during the 1970's, most notably during 1977 when it snowed in Miami and the Bahamas for the only time in recorded history, and temperatures in much of the midwest stayed below freezing for over a month. So of course articles about a new ice age would attract readers, even though any return to ice age conditions would happen over centuries, if it wasn't disrupted by humans.
It really was a lot of snow though, we were out of school for like two weeks in the spring of 1978.
Interestingly, 1980 was the hottest year recorded up to that point. I'll probably never forget that now that I mentioned it to my mom, and she remembered it being super hot because she backed her car into a tree while trying to park in the shade to escape it and that burned it into her memory.
My understanding is that we currently reside in an inter-glacial period within the ice age. If humanity has already engineered the climate of the Earth enough to exit the ice age, then that's quite an accomplishment.
Most people then thought of nuclear winter as more likely.
In the Fort Worth Star Telegram, 27 Sep 1981, is the article "World's mercury inching upward", discussing the science which wouldn't look out of place today. But it wasn't until the end of the 80s that the US government started to take it seriously.
No there was some global cooling whataboutism going on in the late 70's early 80's, but I didn't hear much about it until the late 90's, when we started talking about the 33 year solar cycle.
