The Incredible Shrinking Ice Cap

Cue the climate loonies. The Arctic is "becoming a profoundly different place than we grew up thinking about."

The floating cap of sea ice on the Arctic Ocean shrank this summer to what is probably its smallest size in a century, continuing a trend toward less summer ice that is hard to explain without attributing it in part to human-caused global warming, various experts on the region said today.

The findings are consistent with recent computer simulations showing that a buildup of smokestack and tailpipe emissions of greenhouse gases could lead to a profoundly transformed Arctic later this century in which much of the once ice-locked ocean is routinely open water in summers.

It also appears that the change is becoming self sustaining, with the increased open water absorbing solar energy that would be reflected back into space by bright white ice, said Ted A. Scambos, a scientist at the National Snow and Ice Data Center in Boulder, Colo., which compiled the data along with NASA.

"Feedbacks in the system are starting to take hold," Dr. Scambos said. "The consecutive record-low extents make it pretty certain a long-term decline is underway."

Read on.