The unprecedented and rising amounts of greenhouse gases added to the atmosphere each year AND the speed at which we are altering the energy balance of the earth are completely out of the range of proven earth history of hundreds of thousands of years.
Thanks to Mark Lacey and the Progressive Forum in Houston and the Presentation and Technology Services department of the University of Montana for the recordings of this lecture.
Dr. Hansen's writings are at <www.columbia.edu/~jeh1>
Dr. James Hansen is one of the few scientists who have consistently warned that the impact that humans have on the climate is bringing about changes that are faster than we ever believed and may be irreversible if action is not taken now.
Hansen is Director of the NASA Institute for Space Studies in New York City and taches at Columbia. Since the late 1970s, he has worked on studies of the Earth's climate.
Hansen has run afoul of government censors since the 1980s. Repeatedly his testimony before Congress was suppressed or re-written.
In this October 2007 talk Hansen goes back into earth�s history, times when tectonic plates crashed into each other, and when the Himalayas and Andes mountain chains pushed up - to prove his point that the earth, for several million years and through dramatic cycles of ice ages and warm periods, existed in a changing energy balance in which the composition of the atmosphere, the effects of the oceans and polar ice sheets and of the heat of the sun affected each other.
Hansen says that these mechanisms that cause long term climate change are now completely in the control of people. The unprecedented and rising amounts of greenhouse gases added each year AND the speed at which we are altering the energy balance of the earth are completely out of the range of proven earth history of hundreds of thousands of years. Hansen fears that we may soon make these changes irreversible by reaching feedback mechanism or tipping points such as the melting of the ice sheets that has already begun on Greenland and West Antarctica.
