"Ninety-seven percent of the surface of Greenland’s ice sheet melted in 2012, a level of ice melt the island hasn’t seen since 1889, according to Kaitlin Keegan, a Dartmouth [engineering] research associate who studies arctic ice," writes QUARTZ. "In a typical year, she says, summer temperatures max out at -14°C. But Keegan recalls the surreal feeling of doing fieldwork on the center of Greenland’s ice sheet in the summer of 2012, as temperatures climbed above freezing. 'When the wind was still, you could go outside in a t-shirt,' she says.

"It’s not clear exactly how much meltwater from unexpected areas like southwest Greenland should alter our predictions for sea level rise. But researchers aren’t optimistic. 'Sea-level rise is an area of climate-change research where there are a lot of unknowns,' Keegan says. 'But if you take ice mass off of Greenland and put it directly into the sea at a faster rate than anyone is modeling, that would imply that sea-level projections are maybe a little conservative.'"