It's been a bad week for ice. Last Tuesday, researchers announced that the Eastern Antarctic Ice Shelf-previously thought to be stable or even growing-is actually melting alarmingly fast. And yesterday (Jan. 21), a new study found that southwest Greenland-another area where ice is believed to be safe-is dumping more meltwater into the ocean than any other region of the icy island.
Both of these developments spell trouble for coastal communities threatened by rising tides.
"We're going to see faster and faster sea-level rise for the foreseeable future," Michael Bevis, lead author of the Greenland study, said in a statement. "Once you hit that tipping point, the only question is: How severe does it get?"
Ninety-seven percent of Greenland's ice sheet melted in 2012, a level of ice melt the island has not seen lakes since 1889, according to Kaitlin Keegan, a Dartmouth research associate who studies arctic ice. In a typical year, she says, summer temperatures max out at -14 ° C. But Keegan recalls the surreal feeling of doing fieldwork at 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 it's melted from unexpected areas like southwest Greenland should age. But researchers are not optimistic. "Sea-level rise is at an area of climate-change research where there are a lot of unknowns," Keegan says. That is just another indication. "
" This is just another indication 20 years from now, "says Eric Klein, a geological science professor at the University of Alaska, who was not involved with the study. These changes are not distant-not in terms of time or space. If we are loose from Greenland or Antarctica and seas rise, that will be felt globally, not just in the Arctic or the Antarctic. "