December 2011 saw the end of a five-year effort to recover the longest ice core ever drilled by the US. About half of the more than two-mile core, taken from the West Antarctic Ice Sheet Divide, has been now been analyzed, taking scientists back through 30,000 years of annual ice layers. And what they've learned, per their new study in Nature, is that Antarctica wasn't late to the party during the planet's last ice age. As Science World Report explains, the Northern Hemisphere's ice age ended some 20,000 years ago, but scientists believed West Antarctica didn't experience that end for another 2,000 years.
But the ice core indicates warming happened between 2,000 and 4,000 years earlier than thought, syncing it with the rest of the planet. "Sometimes we think of Antarctica as this passive continent waiting for other things to act on it," says one researcher. "But here it is showing changes before it 'knows' what the north is doing." Researchers say that better understanding the past could help them better predict what's coming: LiveScience calls West Antarctica "one of the fastest-warming places on the planet" today; the region's center has warmed three times faster than the average rate of global warming, some 4.4 degrees since 1958.