Can seaweed help curb global warming?

It's time for planetary-scale interventions to combat climate change -- and environmentalist Tim Flannery thinks seaweed can help. In a bold talk, he shares the epic carbon-capturing potential of seaweed, explaining how oceangoing seaweed farms created on a massive scale could trap all the carbon we emit into the atmosphere. Learn more about this potentially planet-saving solution -- and the work that's still needed to get there.