James Hansen: Why I Must Speak Out About Climate Change
Top climate scientist James Hansen tells the story of his involvement in the science of and debate over global climate change. In doing so he outlines the overwhelming evidence that change is happening and why that makes him deeply worried about the future.
Other Videos That May Interest You:
Sean Carroll: Distant Time and the Hint of a Multiverse
At TEDxCaltech, cosmologist Sean Carroll attacks -- in an entertaining and thought-provoking tour through the nature of time and the universe -- a deceptively simple question: Why does time exist at all? The potential answers point to a surprising view of the nature of the universe, and our place in it.Underwater Astonishments
David Gallo shows jaw-dropping footage of amazing sea creatures, including a color-shifting cuttlefish, a perfectly camouflaged octopus, and a Times Square's worth of neon light displays from fish who live in the blackest depths of the ocean.Cameron Russell: Looks Aren't Everything. Believe Me, I'm a Model.
In this fearless talk, Model Cameron Russell takes a wry look at the industry that had her looking highly seductive at barely 16-years-old.Jok Church: A Circle of Caring
In this 3-minute talk, cartoonist and educator Jok Church tells a moving story of the teacher who cared for him when no one else did -- and how he returned the favor.Stewart Brand: The dawn of de-extinction. Are you ready?
This video is Stewart Brand's Ted lecture on the scientific challenges and moral issues surrounding the resurrection of extinct species.





