Leonardo DiCaprio and Arnold Schwarzenegger produce and narrate new documentaries 'Ice on Fire' and 'Wonders of the Sea,' as celebrties try to put spotlight on calls for climate change action.
"We don't need advanced technology, Mother Nature has seaweeds and shellfish which sequester five times more carbon than land-based plants," said Bren Smith, winching a glistening haul of glossy brown kelp out of the sea.
