The latest Radio Ecoshock show, PEAK CLIMATE, is good:
We start out with Dr. Peter Ward author of the revolutionary climate book "Under A Green Sky." Peter has just returned from an exploratory trip in Australia, and will head to Antarctica later this year.
Dr. Ward has summarized the newest science which shows that 4 out of the past 5 great extinctions were not caused by asteroid hits - but by wrenching and deadly climate change. The cause? Carbon dioxide belching out of volcanoes. But now we are the volcanoes - and the end result may be the same: out of control climate turbulence followed by the deafening silence of mass extinctions.
He is also very concerned about sea level rise, MP3 here:
http://www.ecoshock.net/eshock08/ES_080912_Show_Lo...
Also this recent talk by Robert Jensen is worth a listen:
THE OLD FUTURE IS GONE Progressive Politics in Cascading Crisis and the Struggle for Strategy. Dr. Robert Jensen, author & Professor of Journalism at Texas U Recorded in Vancouver 080811. Speech 42 min
http://www.ecoshock.org/DNspeeches.html