I think this is what your talking about:
[quote:e4635]According to the report, urgent action is needed to stop the global average temperature rising by 2 degrees Celsius (3.6 degrees Fahrenheit) above the level of 1750 the approximate start of the Industrial Revolution when mankind first started significantly adding carbon dioxide to the atmosphere.
Beyond such a rise, "the risks to human societies and ecosystems grow significantly," the report said, adding that there would be a danger of "abrupt, accelerated, or runaway climate change." It warned of "climatic tipping points" such as the Greenland and West Antarctic ice sheets melting and the Gulf Stream shutting down.
No accurate temperature readings were available for 1750, the report said, but since 1860 the global average temperature has risen by 0.8 percent to 15 degrees Celsius (59 degrees Fahrenheit). [/quote:e4635]
http://abcnews.go.com/Technology/wireSt ... SFeeds0312
I posted a topic on this when this study was released as well back in Jan.