"When the ice thins to a vulnerable state, the bottom will drop out and we may quickly move into a new, seasonally ice-free state of the Arctic," says Mark Serreze, a senior researcher at the National Snow and Ice Data Center at the University of Colorado at Boulder and lead author of the study published in the journal Science today.
"I think there is some evidence that we may have reached that tipping point, and the impacts will not be confined to the Arctic region."


















QUAKE MAPPING


