Ice in the Arctic and Antarctica plays a critical role in maintaining life on Earth, and it is melting faster than previously thought. This is threatening our planet with potentially massive sea-level rise, weather disruptions and further global warming. Horizons moderator William Brangham explores the fate of ice on Earth with science correspondent Miles O’Brien and glaciologist Erin Pettit. #pbsnewshour #newshour #pbsnews #iceburg #antartica #science #meltingice #ice #climatechange