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1,500,551 views | David Keith • TEDSalon 2007 Hot Science

A critical look at geoengineering against climate change

Environmental scientist David Keith proposes a cheap, effective, shocking means to address climate change: What if we injected a huge cloud of ash into the atmosphere to deflect sunlight and heat?

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

Environmental scientist David Keith proposes a cheap, effective, shocking means to address climate change: What if we injected a huge cloud of ash into the atmosphere to deflect sunlight and heat?

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

About the speaker

Environmental scientist

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David Keith studies our climate, and the many ideas we've come up with to fix it. A wildly original thinker, he challenges us to look at climate solutions that may seem daring, sometimes even shocking.

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