# 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.

- Kind: Talk
- Year: 2012
- Runtime: 17 min
- By: TED.com
- Genres: Education, Science
- Archive: [Internet Archive](https://archive.org/details/JamesHansen_2012)
- Licence or status: [CC BY-NC-ND 3.0](http://creativecommons.org/licenses/by-nc-nd/3.0/) (as the archive states it)
- Who can watch: Tweens profiles and older (the archive gives no rating; placed by Invisible Network from its collection and subjects)

[Watch now](https://invisiblenetwork.ai/watch/archive/ia/JamesHansen_2012?play=1)