Here's a new TED Talk from Dr. James Hansen, NASA climate scientist. Dr. Hansen explains how he wrote a paper in 1981 predicting "the 21st century would see shifting climate zones, creation of drought prone regions in North America and Asia, erosion of ice sheets, rising sea levels, and opening of the fabled Northwest passage. All of these impacts have since either happened or are now well underway."
If you're at the office and can't watch video, read a good summary of Hansen's talk from ClimateProgress.org.
It's a stark reminder that while polluters & their allies accuse climate scientists of being "alarmist," the predictions of climate scientists to this point have more often been too conservative. The United Nations' Intergovernmental Panel on Climate Change just issued its Fourth Assessment in 2007, but many climate scientists already think its predictions were far too cautious given our rapid climate changes and the continued acceleration of global carbon pollution.
By the way, are you familiar with TED Talks? The acronym stands for Technology, Entertainment & Design and the organization describes itself simply as a "nonprofit devoted to Ideas Worth Spreading." Their podcasts are indispensable - brilliant ideas explained in easy to understand terms in around 15 minutes.