There were books by "futurists" to that effect and some science fiction stories, but reputable scientists? Hardly. If you think back, which "scientist" was it that claimed we were about to enter a new Ice Age? None, it was a reporter at Time Magazine who had (probably accidentally) learned about Milancovitch Cycles, actual climatologists (there were a few then) already knew we were getting warmer and together with astronomers put together the first climate models to explain the gross temperature ranges of Venus, Earth and Mars. Economists were the only people surprised by economic growth in India and China, and there aren't many of those who could be called "scientists" much less reputable. And even politicians as ignorant as Ronnie Raygun were under no illusion that the Cold War was a permanent state.
Are you sure that you actually remember **anything** from the 1970s?