Ice-free summers in the Arctic?

The Paris agreement is an international climate change treaty signed earlier this year by 192 countries and it aims to mitigate man-made global warming. It kicks in from this week. But will its targets be sufficient? Over half of the Arctic sea ice area has been lost in the past 40 years and we may yet lose all of it. That's according to a new study from the Max Plank Institute for Metrology in Hamburg. Kerstin Göpfrich spoke to study's author Dirk Notz.