Ideas worth spreading

Why I must speak out about climate change

1,668,649 views | James Hansen • TED2012

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.

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.

This talk was presented at an official TED conference. TED's editors chose to feature it for you.

Join Citizens' Climate Lobby and let your representatives know where you stand on climate change.

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About the speaker

James Hansen

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James Hansen has made key insights into our global climate -- and inspired a generation of activists and scientists.

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This talk was presented at an official TED conference. TED's editors chose to feature it for you.

Join Citizens' Climate Lobby and let your representatives know where you stand on climate change.

Subscribe to Dr. Hansen's newsletter and get updates on his program on climate science, awareness and solutions.