Antarctic sea ice at record lows, ice melting warning

Antarctic sea ice hits record lows for three consecutive years, with minimum extent under two million square kilometers. Melting ice could lead to catastrophic sea level rise. Nearly half of Antarctica's ice shelves have reduced in volume in the past 25 years. Scientists warn that human emissions of greenhouse gases are causing continued global warming, with temperatures already 1.2 degrees Celsius hotter than pre-industrial levels. It may be too late to reverse the trend.