http://bit.ly/w1bCQY Listen to presentations by NASA climate scientist James Hansen, and best-selling author and science writer Cris Mooney at 2012 AAAS.

Just back from the American Academy for the Advancement of Science annual conference 2012, this is Alex Smith. I've recorded two of the best speechs of the weekend gathering of thousands of scientists, held this year in Vancouver, Canada.

Download/listen to James Hansen (29 min) CD Quality or Lo-Fi

Download/listen to Chris Mooney (29 min) CD Quality or Lo-Fi

Dr. James Hansen, head of the NASA Goddard Institute for Space Studies, warns it isn't enough to reduce our emissions. We must actually take carbon dioxide back out of the air, to avoid entering a new and dangerous age of greenhouse living.

We are currently at 392 parts per million CO2 in the atmosphere, and rising rapidly. The target Hansen says is 350 parts per million. That is the level where the Polar ice, which regulates the climate humans have known for the past 10,000 years, will remain on planet Earth.

Chris Mooney, author of "The Republican War on Science," says scientists fail to communicate the danger of climate change, because they wrongly believe mere facts will convince the public.

Instead, Mooney outlines studies showing humans use facts to bolster pre-existing beliefs about the world. There are large differences in the basic personalities of those who gravitate toward the Right and Left of politics.

We get a sneak preview from Mooney's upcoming book.

Recorded by Alex Smith Feb 19, 2012 in Vancouver, Canada at the event "Climate Solutions: The Challenges of Getting to 350".