Quote:
I remember, being an earth science student in the 1980's, that global COOLING was the scare back then. But who really knows, one way or the other, when a single volcanic eruption puts out more greenhouse gases than all mankind over several years. (Not stopping to look up the data, but it's there. I'll edit when I stumble across it.)


I thought it was the highly IR reflective sulfate aerosols high in the troposphere due to sulfur dixoide released by volcanoes which cause cooling rather than heating.

http://asd-www.larc.nasa.gov/SOLAR/learning-volcano.html

As for cooling period during the late 1960s early 1970s I thought it was Project Starfish which caused that.