Tonight a friend asked about global cooling, and why it was thought we were at risk

[XemaSab]

of the earth getting cooler 30 years ago.

What was the rationale for that and why was the rationale flawed?

Thanks.

[Richard D]

1. Here ya go.

http://en.wikipedia.org/wiki/Global_cooling

[Riktor]

2. Sample selection

The mass hysteria surrounded the "cooling crisis" of the 1970s was due to a misunderstanding of climatology and the causes of ice ages. The media rallied around a graph indicating declining temperatures from the 1940s through the 1970s and jumped to their own conclusions, while climatologists maintained the data was not significant enough to draw any kind of prediction whatsoever. The "cooling crisis" was a fabrication of the media, and was not backed up by any reputable scientific publications.

On a lighter note, the hysteria inspired The Clash to pen this gem,

The ice age is comin', the sun's zoomin' in

[Viking12]

3. ...another solid takedown of the 'cooling' myth

"The state of the science at the time (say, the mid 1970's), based on reading the papers is, in summary: "…we do not have a good quantitative understanding of our climate machine and what determines its course. Without the fundamental understanding, it does not seem possible to predict climate…" (which is taken directly from NAS, 1975). In a bit more detail, people were aware of various forcing mechanisms - the ice age cycle; CO2 warming; aerosol cooling - but didn't know which would be dominant in the near future. By the end of the 1970's, though, it had become clear that CO2 warming would probably be dominant; that conclusion has subsequently strengthened."

http://www.realclimate.org/index.php/archives/2005/01/the-global-cooling-myth/