"A new study shows how much natural variability is boosting the rate of melting in the Arctic, which might be free of sea ice sooner than expected."
"A new study zeroes in on just how much of the Arctic sea ice's precipitous decline in recent decades is attributable to manmade global warming and how much is due to natural processes, finding that between 50 and 70 percent is caused by mankind.
By studying air current patterns, researchers determined that between 30 and 50 percent of the decline in summer sea ice in the Arctic since 1979 may be due to natural processes, for the first time breaking down just how much melting could be attributed to each cause. The study was published Monday in the journal Nature Climate Change.
"If we look to Earth as a whole, the global temperature rise is definitely due to anthropogenic forcing in the last 100 years. There's no question of that," said author Qinghua Ding, a professor at the University of California Santa Barbara. "But if we zoom in, some internal role comes in to have some impact."
Arctic sea ice has been rapidly declining since satellites first started tracking it in 1979, and according to NASA, roughly 13.3 percent of the ice disappears every decade."