REPORT / INTERNATIONAL NEWS

Old, "multiyear" ice -- the glue that holds the polar ice cap together and forms the Arctic's defense against encroaching warming -- is slowly disintegrating, a process that is plain to see from the air.

Thick ice floes used to be kilometers (miles) wide just over a decade ago, said Jim Overland, a sea-ice expert with the U.S. National Oceanic and Atmospheric Administration, who has been surveying the site since the 1990s.