Greenland’s magnificent glaciers are melting — faster and faster.

A team of NASA scientists are trying to find out the reason why.

“When you look at the glacier like that, from the vantage point of a helicopter, it looks like it’s going to be here forever,” says Eric Rignot, a senior research scientist at NASA and professor at UC Irvine in a new 360° film from FRONTLINE, NOVA and Emblematic Group. “How could it possibly go away?”

The warm air that comes into contact with the glaciers is one factor at play. But the NASA team has found a troubling development underwater as well.

Their findings mean that predictions for global sea level rise may be too conservative. And coastal cities like Miami or Mumbai could be at a higher risk of catastrophic flooding.