www.ted.com 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?tedtalks is a daily video podcast of the best talks and performances from the TED Conference, where the world’s leading thinkers and doers are invited to give the talk of their lives in 18 minutes — including speakers such as Jill Bolte Taylor, Sir Ken Robinson, Hans Rosling, Al Gore and Arthur Benjamin. TED stands for Technology, Entertainment, and Design, and tedtalks cover these topics as well as science, business, politics and the arts. Watch the Top 10 tedtalks on TED.com, at www.ted.com