Is it true climate scientists were afraid of gobal COOLING in the 1970s?

Yes.

1. Newsweek article from April 28, 1975: "The Cooling World"
http://denisdutton.com/newsweek_coolingworld.pdf

2. Also Time Magazine, June 24, 1974.
http://www.time.com/time/magazine/article/0,9171,944914-1,00.html

3. Letter from 42 American and European scientists warning President Nixon about global cooling.
http://fabiusmaximus.wordpress.com/2009/10/21/letter/

4. Other examples:

Science Digest (February 1973) reported that "the world's climatologists are agreed" that we must "prepare for the next ice age." The Christian Science Monitor ("Warning: Earth's Climate is Changing Faster Than Even Experts Expect," Aug. 27, 1974) reported that glaciers "have begun to advance," "growing seasons in England and Scandinavia are getting shorter" and "the North Atlantic is cooling down about as fast as an ocean can cool."